Danfoss PSH038 scroll PSH051 to 077 serie - GB - SI Application Guide


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Danfoss PSH038 scroll PSH051 to 077 serie - GB - SI Application Guide | Manualzz

Application guidelines

Danfoss scroll compressors

PSH051 to 077

50-60 Hz - R410A

http://cc.danfoss.com

Application Guidelines Content

Compressor features ............................................................................................................5

Nomenclature and specifications ........................................................................................6

Compressor nomenclature ...................................................................................................................................................................... 6

Compressor specifications ....................................................................................................................................................................... 6

Performance data - 50 Hz .....................................................................................................7

Cooling ............................................................................................................................................................................................................ 7

Heating ............................................................................................................................................................................................................ 7

Performance data - 60 Hz .....................................................................................................8

Cooling ............................................................................................................................................................................................................ 8

Heating ............................................................................................................................................................................................................ 8

Dimensions ...........................................................................................................................9

PSH051 ............................................................................................................................................................................................................ 9

PSH064 ..........................................................................................................................................................................................................10

PSH077 ..........................................................................................................................................................................................................11

Electrical data, connections and wiring ............................................................................12

Connection details ....................................................................................................................................................................................12

Suction and discharge connections ...................................................................................................................................................12

Oil sight glass ..............................................................................................................................................................................................12

Oil equalisation connection...................................................................................................................................................................12

Oil drain connection .................................................................................................................................................................................12

Schrader ........................................................................................................................................................................................................12

Liquid injection valve ...............................................................................................................................................................................12

Motor voltage .............................................................................................................................................................................................13

Voltage unbalance ....................................................................................................................................................................................13

Electrical data ..............................................................................................................................................................................................13

Wiring Connections ..................................................................................................................................................................................14

General wiring information ...................................................................................................................................................................15

Electrical box knock-out dimensions .................................................................................................................................................16

IP rating .........................................................................................................................................................................................................16

Electrical box temperature .....................................................................................................................................................................16

Approval and certifications ...............................................................................................17

Approvals and certificates ......................................................................................................................................................................17

Pressure equipment

Machines directive directive 2014/68/EU ..................................................................................................................17

Low voltage directive 2014/35/EU ..................................................................................................................................17

2006/42/EC .......................................................................................................................................17

Electromagnetic compatibility directive 2014/30/EU ..................................................................................................................17

Operating conditions .........................................................................................................18

Refrigerant and lubricants......................................................................................................................................................................18

Motor supply ...............................................................................................................................................................................................18

Compressor ambient temperature .....................................................................................................................................................18

Compressor protection ...........................................................................................................................................................................19

Phase sequence and reverse rotation protection ..........................................................................................................................20

Application envelope ...............................................................................................................................................................................20

Pressure transmitter accuracy and range .........................................................................................................................................23

Liquid injection ..........................................................................................................................................................................................23

Discharge temperature protection .....................................................................................................................................................23

Malfunction protection ...........................................................................................................................................................................24

High and low pressure protection.......................................................................................................................................................24

Cycle rate limit ............................................................................................................................................................................................26

Data management ..............................................................................................................27

Data storage displayed by OCS ............................................................................................................................................................27

MMIMYK and MMIGRS Electronic controllers..................................................................................................................................27

Data read-out ..............................................................................................................................................................................................28

Data storage recovery ..............................................................................................................................................................................28

FRCC.PC.021.A5.02

3

Application Guidelines Content

CAN-Bus and Modbus RS485 Communication .................................................................29

Compressor address set-up for CAN-Bus and Modbus ...............................................................................................................29

CAN-Bus and Modbus communication with OCS .........................................................................................................................30

Measurements ............................................................................................................................................................................................31

Alarms and warning .................................................................................................................................................................................32

System design recommendations .....................................................................................33

General ..........................................................................................................................................................................................................33

Essential piping design considerations .............................................................................................................................................33

Off-cycle migration ...................................................................................................................................................................................34

Liquid flood back .......................................................................................................................................................................................35

Oil equalisation ..........................................................................................................................................................................................36

Specific application recommendations ............................................................................37

Low ambient application ........................................................................................................................................................................37

Low load operation ...................................................................................................................................................................................38

Brazed plate heat exchangers ...............................................................................................................................................................38

Electronic expansion valve ....................................................................................................................................................................38

Reversible heat pump systems .............................................................................................................................................................38

Discharge line and reversing valve .....................................................................................................................................................38

Defrost and reverse cycle .......................................................................................................................................................................39

Suction line accumulator ........................................................................................................................................................................39

Water utilizing systems ............................................................................................................................................................................39

Sound and vibration management ...................................................................................40

Starting sound level..................................................................................................................................................................................40

Running sound level ................................................................................................................................................................................40

Stopping sound level ...............................................................................................................................................................................40

Installation ..........................................................................................................................41

Compressor handling and storage......................................................................................................................................................41

Compressor mounting ............................................................................................................................................................................41

Parallel mounting ......................................................................................................................................................................................42

Tandem and trio Handling .....................................................................................................................................................................44

Compressor holding charge ..................................................................................................................................................................44

System cleanliness ....................................................................................................................................................................................45

Tubing ............................................................................................................................................................................................................45

Brazing and soldering ..............................................................................................................................................................................45

System pressure test ................................................................................................................................................................................47

Leak detection ............................................................................................................................................................................................47

Vacuum evacuation and moisture removal .....................................................................................................................................47

Filter driers ...................................................................................................................................................................................................48

Refrigerant charging ................................................................................................................................................................................48

Refrigerant charge limit ..........................................................................................................................................................................48

Insulation resistance and dielectric strength ..................................................................................................................................49

Commissioning ..........................................................................................................................................................................................50

Oil level checking and top-up ...............................................................................................................................................................50

Ordering information and packaging ...............................................................................51

Packaging .....................................................................................................................................................................................................51

Ordering information ...............................................................................................................................................................................52

Industrial pack ............................................................................................................................................................................................52

Accessories ..........................................................................................................................53

Valves, adapters, connectors & gaskets for use on suction and discharge connections .................................................53

Acoustic hoods and spare parts ...........................................................................................................................................................54

Lubricants / oils ..........................................................................................................................................................................................55

Miscellaneous .............................................................................................................................................................................................55

Sensors & cables ........................................................................................................................................................................................55

Communication tools ..............................................................................................................................................................................55

4 FRCC.PC.021.A5.02

Application Guidelines Compressor features

Danfoss PSH scroll compressor is optimized for heat pump applications. Beside scroll elements pressure ratio optimization, PSH includes 2 major new technologies: liquid injection and Operating

Control System (OCS).

PSH scroll compressor is also equipped with several prewired devices such as discharge temperature sensor, surface sump heater (SSH) and Liquid Injection Valve (LIV).

Discharge Temperature Sensor

Operating Control System (OCS):

Motor protection

Liquid Injection Valve control

Operating envelope monitoring

Data storage management

Oil surface sump heater control

CAN-Bus/ Modbus Connections

Liquid injection valve (LIV)

Pre-mounted surface sump heater

(SSH) with insulation

Liquid injection is controlled by a discharge gas temperature sensor connected to the OCS.

CAN-Bus connection between manifolded compressors allows the use of only one HP sensor and one LP sensor.

A Modbus connection allows the information exchange between the unit main board (PLC) and the compressor’s boards (OCS).

FRCC.PC.021.A5.02

5

Application Guidelines Nomenclature and specifications

Danfoss PSH scroll compressors for R410A are available as single compressors.

The example below presents the compressor nomenclature which equals to the technical reference as shown on the compressor nameplate.

Compressor nomenclature

Heat pump application

P

Scroll (commercial / large commercial)

Lubricant

R410A, POE

Heating capacity in kW at 50Hz

-7°C/50°C/SH5K/SC5K

S H 064 A 4 A

Code numbers for ordering are listed in section

“Ordering information and packaging” at the end of this document.

K A

Evolution index

Motor protection type

K : 230V OCS

Connections

A : brazed connections

Motor voltage code

UL index

4 : 380-415V/3~/50 Hz - 460V/3~/60 Hz

9 : 380V/3~/60 Hz

Compressor specifications

50Hz

Model

PSH051

PSH064

PSH077

PSH051

Nominal

Heating capacity

W

53337

65481

80303

64057

Nominal

Cooling capacity

W

36167

44683

55051

43436

60Hz

Conditions :

PSH064

PSH077

78643

96114

53665

66061

Evaporating temperature: -7°C

Power Input

 Displacement at nominal speed: 2900rpm at 50Hz. 3500rpm at 60Hz

 Net weight with oil charge

Heating

COP

W

17170

21575

25979

W/W

3.11

3.04

3.09

20621

25911

3.11

3.04

31175 3.08

Condensing temperature: 50°C

Cooling

COP

Swept volume

W/W

2.11

2.07

2.12

cm 3 /rev

227.6

286.2

344.6

2.11

2.07

227.6

286.2

2.12

Superheat: 5K

344.6

Displacement

 m 3 /h

39.6

49.8

60

47.8

60.1

72.4

Subcooling:5K

Oil charge

Net weight

 dm 3

6.7

6.7

6.7

6.7

6.7

108

153

6.7

161

Refrigerant: R410A kg

108

153

161

6 FRCC.PC.021.A5.02

Application Guidelines Performance data - 50 Hz

Cooling

Model

PSH051-4

PSH064-4

PSH077-4

Pe

(kW)

Cooling

(W)

Pe

(kW)

Cooling

(W)

Pe

(kW)

Cooling

(W)

Pe

(kW)

Cooling

(W)

Pe

(kW)

Cooling

(W)

Pe

(kW)

Te -30 -20 -10 -5 0 5

20 19 440 8.76

30 420 9.74

45 380 11.13

54 580 12.02 65 060 13.07 76 910 14.28

Cooling

(W)

10

-

Pe

(kW)

Cooling

(W)

15

-

Pe

(kW)

Cooling

(W)

20

-

Pe

(kW)

-

30 17 380 10.34 27 520 11.24

41 210 12.48 49 620 13.26 59 200 14.19 70 060 15.27 82 270 16.52 95 950 17.96

-

40 15 160 12.37 24 440 13.22 36 850 14.34 44 470 15.05 53 150 15.87 63 000 16.83 74 100 17.94 86 560 19.23 100 470 20.70

50 12 680 14.92 21 080 15.76 32 190 16.80 39 000 17.44 46 780 18.18

55 610 19.03 65 600 20.03 76 830 21.17

89 410 22.50

60 17 310 18.93

27 110 19.92

33 110 20.51 39 970 21.19

47 780 21.96 56 640 22.85 66 640 23.88 77 880 25.10

68 22 660 22.95 28 010 23.52 34 120 24.15

41 110 24.87 49 060 25.69 58 070 26.64

20 24 450 11.18

38 160 12.35 57 180 13.98 69 030 15.06 82 630 16.34 98 110 17.88

-

30 21 960 13.06 34 460 14.24 51 610 15.70 62 280 16.63 74 530 17.72 88 500 19.02 104 340 20.56 122 190 22.36

-

-

-

40 19 170 15.36 30 520 16.66 45 870 18.07 55 390 18.89 66 330 19.85 78 830 20.97 93 020 22.28 109 060 23.83 127 090 25.60

50 15 900 18.13 26 180 19.65 39 780 21.11

48 190 21.90 57 850 22.77 68 910 23.77 81 500 24.91 95 770 26.24 111 850 27.80

60

68

-

-

-

-

21 260 23.25 33 190 24.87 40 520 25.68 48 930 26.53 58 580 27.45 69 600 28.48 82 130 29.66 96 310 31.00

27 440 28.43 33 920 29.29 41 370 30.16 49 910 31.06 59 690 32.04 70 860 33.13

-

-

-

-

20 30 220 13.72 46 750 15.15 69 640 17.37 83 940 18.81 100 370 20.46 119 130 22.34

-

30 27 030 15.93 42 390 17.20 63 380 19.21 76 450 20.51 91 480 22.02 108 660 23.74 128 180 25.68 150 210 27.85

-

-

-

-

40 23 650 18.81 37 630 19.97 56 520 21.81 68 280 23.00 81 810 24.38 97 310 25.97 114 970 27.76 134 960 29.76 157 480 32.00

50 20 030 22.53 32 430 23.63 49 030 25.34 59 370 26.44 71 310 27.73 85 040 29.19 100 740 30.85 118 590 32.71 138 790 34.80

60 26 740 28.33 40 860 29.96 49 680 31.00 59 920 32.21 71 780 33.59 85 420 35.14 101 050 36.88 118 830 38.80

68 33 790 34.56 41 330 35.57 50 150 36.73 60 430 38.05 72 370 39.53 86 130 41.19

-

Heating

Model

PSH051-4

PSH064-4

PSH077-4

Te -30

Pe

(kW)

Heating

(W)

-20

Pe

(kW)

Heating

(W)

-10

Pe

(kW)

Heating

(W)

-5

Pe

(kW)

Heating

(W)

0

Pe

(kW)

Heating

(W)

5

Pe

(kW)

Heating

(W)

10

Pe

(kW)

Heating

(W)

15

Pe

(kW)

Heating

(W)

20

Pe

(kW)

20 28 200 8.76

40 160 9.74

56 500 11.13 66 600 12.02 78 120 13.07 91 190 14.28

-

30 27 720 10.34 38 750 11.24 53 680 12.48 62 880 13.26 73 400 14.19 85 330 15.27 98 790 16.52 113 910 17.96

-

-

-

-

40 27 530 12.37 37 660 13.22 51 190 14.34 59 510 15.05 69 020 15.87 79 830 16.83 92 050 17.94 105 790 19.23 121 160 20.70

50 27 600 14.92 36 840 15.76 48 990 16.80 56 440 17.44 64 950 18.18 74 640 19.03 85 620 20.03 98 000 21.17 111 900 22.50

60 36 240 18.93 47 030 19.92 53 620 20.51 61 150 21.19 69 730 21.96 79 490 22.85 90 520 23.88 102 930 25.10

68 45 620 22.95 51 520 23.52 58 270 24.15 65 980 24.87 74 750 25.69 84 710 26.64

-

20 35 230 11.18

50 070 12.35 70 660 13.98 83 550 15.06 98 380 16.34 115 340 17.88

-

30 34 550 13.06 48 190 14.24 66 750 15.70 78 300 16.63 91 610 17.72 106 840 19.02 124 160 20.56 143 750 22.36

-

-

-

-

40 33 970 15.36 46 580 16.66 63 280 18.07 73 600 18.89 85 460 19.85 99 040 20.97 114 510 22.28 132 030 23.83 151 790 25.60

50 33 380 18.13

45 120 19.65 60 130 21.11

69 300 21.90 79 800 22.77 91 820 23.77 105 510 24.91 121 070 26.24 138 640 27.80

60

68 -

-

-

43 670 23.25 57 170 24.87 65 270 25.68 74 510 26.53 85 040 27.45 97 050 28.48 110 720 29.66 126 200 31.00

54 850 28.43 62 160 29.29 70 440 30.16 79 850 31.06 90 580 32.04 102 790 33.13

-

20 43 550 13.72 61 470 15.15 86 530 17.37 102 210 18.81 120 260 20.46 140 850 22.34

-

30 42 520 15.93

59 110 17.20 82 050 19.21 96 380 20.51 112 880 22.02 131 740 23.74 153 140 25.68 177 280 27.85

-

-

-

-

40 41 940 18.81 57 040 19.97 77 720 21.81 90 630 23.00 105 510 24.38 122 550 25.97 141 950 27.76 163 890 29.76 188 570 32.00

50 41 930 22.53 55 400 23.63 73 660 25.34 85 070 26.44 98 260 27.73 113 410 29.19 130 730 30.85 150 390 32.71 172 600 34.80

60 54 280 28.33 69 980 29.96 79 810 31.00 91 230 32.21 104 420 33.59 119 580 35.14 136 890 36.88 156 550 38.80

68 67 380 34.56 75 900 35.57 85 850 36.73 97 420 38.05 110 790 39.53 126 170 41.19

-

Refrigerant: R410A Frequency : 50 Hz Subcooling: 5K Superheat: 5K

FRCC.PC.021.A5.02

7

Application Guidelines Performance data - 60 Hz

Cooling

PSH051-4

PSH064-4

PSH077-4

Pe

(kW)

Cooling

(W)

Pe

(kW)

Cooling

(W)

Pe

(kW)

Cooling

(W)

Pe

(kW)

Cooling

(W)

Pe

(kW)

Cooling

(W)

Pe

(kW)

Te -30 -20 -10 -5 0 5

20 23 350 10.52 36 540 11.69 54 500 13.36 65 550 14.43 78 130 15.69 92 360 17.15

Cooling

(W)

-

10

Pe

(kW)

-

Cooling

(W)

-

15

Pe

(kW)

-

Cooling

(W)

-

20

Pe

(kW)

-

30 20 870 12.42 33 050 13.50 49 490 14.98 59 590 15.93 71 100 17.04 84 140 18.34 98 810 19.84 115 230 21.57

-

40 18 210 14.86 29 350 15.88 44 260 17.22 53 400 18.07 63 830 19.06 75 660 20.21 89 000 21.55 103 960 23.09 120 660 24.90

50 15 230 17.92 25 310 18.93 38 660 20.18 46 840 20.94 56 180 21.83 66 790 22.86 78 780 24.05 92 270 25.43 107 380 27.00

60

68 -

-

-

20 790 22.73 32 560 23.93 39 760 24.64 48 000 25.44 57 380 26.37 68 020 27.44 80 030 28.68 93 530 30.10

27 220 27.57 33 630 28.24 40 980 29.00 49 370 29.87 58 920 30.86 69 740 31.99

-

20 29 360 13.43 45 840 14.84 68 680 16.80 82 910 18.08 99 240 19.63 117 830 21.47

-

30 26 370 15.68 41 390 17.10

61 980 18.86 74 800 19.97 89 510 21.28 106 290 22.84 125 320 24.69 146 750 26.86

-

-

-

-

40 23 020 18.45 36 650 20.01 55 080 21.70 66 520 22.69 79 660 23.84 94 670 25.18 111 720 26.76 130 990 28.61 152 630 30.80

50 19 100 21.77 31 440 23.60 47 780 25.35 57 870 26.30 69 480 27.35 82 760 28.55 97 880 29.92 115 020 31.52 134 340 33.40

60 25 530 27.92 39 860 29.87 48 660 30.84 58 770 31.86 70 350 32.97 83 590 34.21 98 640 35.62 115 670 37.20

68 32 960 34.15 40 740 35.18 49 680 36.22 59 940 37.31 71 690 38.49 85 100 39.79

20 36 260 16.46 56 100 18.18 83 570 20.85 100 720 22.57 120 440 24.55 142 960 26.81

-

-

-

-

30 32 440 19.12 50 860 20.64 76 050 23.05 91 740 24.61 109 780 26.42 130 400 28.48 153 810 30.82 180 250 33.42

-

40 28 390 22.58 45 160 23.97 67 830 26.17 81 930 27.60 98 170 29.26 116 780 31.16 137 960 33.31 161 960 35.71 188 970 38.40

50 24 040 27.04 38 920 28.35 58 840 30.40 71 240 31.73 85 570 33.27 102 040 35.03 120 880 37.02 142 310 39.26 166 550 41.70

60 32 090 33.99 49 030 35.95 59 610 37.20 71 910 38.65 86 130 40.30 102 510 42.17 121 260 44.25 142 600 46.60

68 40 540 41.47 49 590 42.68 60 180 44.08 72 520 45.66 86 840 47.44 103 360 49.43

-

Heating

PSH051-4

PSH064-4

PSH077-4

Tc

Heating

(W)

Pe

(kW)

Heating

(W)

Pe

(kW)

Heating

(W)

Pe

(kW)

Heating

(W)

Pe

(kW)

Heating

(W)

Pe

(kW)

Heating

(W)

Pe

(kW)

Heating

(W)

Pe

(kW)

Heating

(W)

Pe

(kW)

Te

20

-30 -20 -10 -5 0 5

33 870 10.52 48 230 11.69 67 860 13.36 79 980 14.43 93 820 15.69 109 520 17.15

-

10

-

15

-

30 33 290 12.42 46 540 13.50 64 470 14.98 75 520 15.93 88 150 17.04 102 480 18.34 118 650 19.84 136 800 21.57

Heating

(W)

-

-

20

Pe

(kW)

-

-

40 33 070 14.86 45 230 15.88 61 480 17.22 71 470 18.07 82 890 19.06 95 870 20.21 110 550 21.55 127 050 23.09 145 520 24.90

50 33 140 17.92 44 240 18.93 58 840 20.18 67 780 20.94 78 010 21.83 89 650 22.86 102 830 24.05 117 700 25.43 134 390 27.00

60

68

-

-

-

-

43 520 22.73 56 490 23.93 64 400 24.64 73 440 25.44 83 750 26.37 95 460 27.44 108 710 28.68 123 620 30.10

54 790 27.57 61 880 28.24 69 980 29.00 79 240 29.87 89 780 30.86 101 730 31.99

-

20 42 310 13.43 60 140 14.84 84 870 16.80 100 340 18.08 118 160 19.63 138 530 21.47

-

30 41 490 15.68 57 870 17.10 80 160 18.86 94 040 19.97 110 020 21.28 128 310 22.84 149 110 24.69 172 640 26.86

-

-

-

-

40 40 800 18.45 55 940 20.01 76 000 21.70 88 390 22.69 102 640 23.84 118 950 25.18 137 520 26.76 158 570 28.61 182 300 30.80

50 40 080 21.77 54 180 23.60 72 220 25.35 83 230 26.30 95 840 27.35 110 270 28.55 126 720 29.92 145 400 31.52 166 510 33.40

60 52 450 27.92 68 660 29.87 78 390 30.84 89 480 31.86 102 140 32.97 116 560 34.21 132 970 35.62 151 570 37.20

68 65 880 34.15 74 660 35.18 84 600 36.22 95 900 37.31 108 790 38.49 123 460 39.79

20 52 130 16.46 73 620 18.18 103 670 20.85 122 480 22.57 144 110 24.55 168 800 26.81

-

-

-

-

-

30 50 870 19.12 70 760 20.64 98 270 23.05 115 460 24.61 135 250 26.42 157 850 28.48 183 520 30.82 212 470 33.42

-

40 50 150 22.58 68 260 23.97 93 060 26.17 108 540 27.60 126 380 29.26 146 810 31.16 170 070 33.31 196 380 35.71 225 970 38.40

50 50 100 27.04 66 250 28.35 88 150 30.40 101 830 31.73 117 640 33.27 135 810 35.03 156 570 37.02 180 150 39.26 206 780 41.70

60 64 860 33.99 83 680 35.95 95 480 37.20 109 170 38.65 124 990 40.30 143 160 42.17 163 920 44.25 187 490 46.60

68 80 520 41.47 90 740 42.68 102 670 44.08 116 540 45.66 132 570 47.44 151 010 49.43

-

Refrigerant: R410A Frequency : 60 Hz Subcooling: 5K Superheat: 5K

8 FRCC.PC.021.A5.02

Application Guidelines Dimensions

PSH051

Ø 265.9

652.5

617

208

Ø 257.5

531 ±1.2

301

205.2

143.75

Ø 317.8

Rigid spacer x 4

370.8

304.8

81.7

168.4

345.4

279.4

195

171

183

60°

10°

76 92

4x holes

Ø19.43

434

236

60°

258

353

179

Rigid spacer

29.5 mm

HM 8 bolt

Lock washer

Nut

Flat washer

Rigid spacer

Nut

All dimensions in mm

Flexible grommet (accessory)

HM 8 bolt

Lock washer

Flat washer

Steel mounting sleeve

Rubber grommet

Nut

Compressor base plate

28 mm

FRCC.PC.021.A5.02

9

Application Guidelines Dimensions

PSH064

Rigid spacer

29.5 mm

Ø 333.2

Ø 318.1

693

634

208

492 ±1.2

202.2

301

143.1

76.1

92

Rigid spacer x4

370.8

81.5

304.8

204

195

168.6

345.4

279.4

183

10°

60°

4xhole

Ø19.43

436

238

60°

258

357

179

HM 8 bolt

Lock washer

Nut

Flat washer

Nut

Rigid spacer

All dimensions in mm

Flexible grommet (accessory)

HM 8 bolt

Lock washer

Flat washer

Steel mounting sleeve

Rubber grommet

Nut

Compressor base plate

28 mm

10 FRCC.PC.021.A5.02

Application Guidelines

PSH077

Dimensions

Ø 333.2

725.3

666.3

208

Ø 318.1

524.3 ±1.2

202.2

301

143.1

Rigid spacer x4

370.8

304.8

81.5

204

195

168.6

345.4

279.4

183

60°

10°

76.1

92

4x holes

Ø 19.43

436

238

60°

258

357

179

Rigid spacer

29.5 mm

HM 8 bolt

Lock washer

Nut

Flat washer

Nut

Rigid spacer

All dimensions in mm

Flexible grommet (accessory)

HM 8 bolt

Lock washer

Flat washer

Steel mounting sleeve

Rubber grommet

Nut

Compressor base plate

28 mm

FRCC.PC.021.A5.02

11

Application Guidelines

Connection details

Electrical data, connections and wiring

Suction and discharge connections

Oil sight glass

Oil equalization connection

Oil drain connection

Low pressure gauge port (schrader)

Liquid Injection Valve connection tube

Suction and discharge connections

Oil sight glass

Oil equalisation connection

Oil drain connection

Schrader

Liquid injection valve

PSH051-064-077

AJ-AK

Brazed

Threaded

Rotolock 2"1/4

1/4" SAE flare

1/4" SAE flare

1/4" ODF

Tube ODF

PSH051-064-077

Suction

Discharge

1"5/8

1"1/8

All Danfoss PSH scroll compressors come equipped with a sight glass (1"1/8 - 18 UNF) which may be used to determine the amount

PSH051-064-077 are equipped with a 2"1/4 rotolock connector allowing the use of 2"1/4

- 1"3/8 or 2"1/4 - 1"5/8 sleeve. This connection must be used to mount the oil equalisation line and condition of the oil contained within the sump.

when two or more compressors are mounted in parallel (please refer to section ”Parallel mounting” for details).

The oil drain connection allows oil to be removed from the sump for changing, testing, etc. The fitting contains an extension tube into the oil sump to more effectively remove the oil. The connection is a female 1/4" SAE flare fitting

The oil fill connection and gauge port is a 1/4" male flare connector incorporating a Schrader valve.

The liquid injection valve (LIV) comes equipped with process tube, maintained by a bracket, assembled on compressor shell. This process tube is to be connected with a 1/4" piping to the system liquid line.

During commissioning, check that the LIV coil is correctly positioned on the LIV body. One of the lock pins on the coil must fit into one of the dents on the valve body.

1/4"

Support bracket

Process tube

Coil

Liquid Injection Valve (LIV)

12 FRCC.PC.021.A5.02

Application Guidelines Electrical data, connections and wiring

Motor voltage

Voltage unbalance

50Hz

60Hz

Motor voltage code

Nominal voltage

Voltage range

Nominal voltage

Voltage range

Code 4

380-415V~3

357-440V~3

460V~3

415-506V~3

Code 9

-

-

380V~3

342-418V~3

The operating voltage limits are shown in the table section ”Motor voltage“. The voltage applied to the motor terminals must lie within these table limits during both start-up and normal operations. The maximum allowable voltage unbalance is 2%. Voltage unbalance causes high amperage over one or several phases, which in turn leads to overheating and possible motor damage. Voltage unbalance is given by the formula:

Vavg = Mean voltage of phases 1, 2, 3.

V1-2 = Voltage between phases 1 & 2.

V1-3 = Voltage between phases 1 & 3.

V2-3 = Voltage between phases 2 & 3.

| Vavg - V1-2 | + | Vavg - V1-3 | + | Vavg - V2-3 |

% voltage unbalance= _______________________________________________ x100

2 x Vavg

Electrical data

Compressor models

Motor code 4

Motor code 9

PSH051

PSH064

PSH077

PSH051

PSH064

PSH077

LRA

A

211

248

319

273

315

399

LRA (Locked Rotor Amp)

MCC (Maximum Continuous

Current)

The MCC is the current at which the motor protection trips under maximum load and low voltage conditions. This MCC value is the maximum at which the compressor can be

Max. operating current

Locked Rotor Amp value is the highest average current as measured on mechanically blocked compressor tested under nominal voltage. The

LRA value can be used as rough estimation for

The max. operating current is the current when the compressors operates at maximum load conditions and 10% below nominal voltage

(+15°C evaporating temperature and +68°C condensing temperature). Max. operating current can be used to select cables and contactors.

MCC

66

90

98

A

60

72

83

Maximum operating current

61

79

91

A

50

64

78

Winding resistance

0.57

0.48

0.39

0.38

0.33

0.27

the starting current. However in most cases, the real starting current will be lower. A soft starter can be applied to reduce starting current.

operated in transient conditions and out of the application envelope. Above this value, the OCS will cut-out the compressor to protect the motor.

In normal operation, the compressor current consumption is always less than the Max operating A. value.

FRCC.PC.021.A5.02

13

Application Guidelines

Winding resistance

Electrical data, connections and wiring

Winding resistance is the resistance between phases at 25°C (resistance value +/- 7%).

resistance must be corrected with following formula:

Winding resistance is generally low and it requires adapted tools for precise measurement.

Use a digital ohm-meter, a ”4 wires“ method and measure under stabilised ambient temperature.

Winding resistance varies strongly with winding temperature ; if the compressor is stabilised at a different value than 25°C, the measured

R amb

= R

25°C a + t amb

_________ a + t

25°C t t

R

25°C

R

25°C

: reference temperature = 25°C amb

: temperature during measurement (°C) amb

: winding resistance at 25°C

: winding resistance at tamb

Coefficient a = 234.5

Wiring Connections

CAN-Bus (if manifolded)

MYK / GRS

Modbus

DGT sensor

LP sensor

HP sensor

Liquid Injection Valve (LIV)

M1 M2 control circuit

Surface Sump Heater

OCS power supply

Cover holding screws (x4)

Torque: 2.2 Nm

Danfoss Commercial Compressors supply & connections

Customer supply or Danfoss Commercial Compressors kit on request

Customer supply & connections

Compressor power supply

Operating Control System

(OCS) power supply

Electrical supply is connected to the compressor terminals by Ø 4.8 mm (3/16") screws. The maximum tightening torque is 3 Nm. Use a 1/4" ring terminal on the power leads.

The compressor must be connected to earth with the 5 mm earth terminal screw.

The Operating Control System (OCS) can be supplied with 230V. For 230V OCS, earth connection must be done with a 1/4" faston terminal.

Nominal voltage

230V ~1 50/60Hz

To avoid personal injury, earth continuity must be checked before switching the power on.

Provide separate electrical supply for the OCS so the heater remains energized when the machine is out of service (eg seasonnal shutdown).

Voltage range

207-254V ~1 50Hz - 180-254V ~1 60Hz

14 FRCC.PC.021.A5.02

Application Guidelines

OCS connections

HP and LP sensor connection

Electrical data, connections and wiring

The OCS comes preinstalled within the compressor electrical box.

All needed connectors are plugged in place on the OCS and connector positions are marked on the transparent OCS protection cover.

The compressor comes with prewired OCS connections for:

• discharge gas temperature sensor (DGT)

• surface sump heater (SSH)

• motor protection

• phase monitoring

• liquid injection valve (LIV) not connected to the discharge temperature sensor that is pre-installed on the upper shell.

This cable has to be connected to the sensor before switching on the power.

Low pressure and high pressure transmitters connection to the OCS are mandatory for compressor operation (envelope monitoring), refer to ”pressure transmitter accuracy and range“ section.

Note that to avoid handling and transportation issues, the discharge gas temperature cable is

Shielded cable is mandatory for HP and LP sensor connections. Cable shield must be connected on sensor side only.

High pressure sensor connection

LP and HP signals can also be transferred via Modbus, refer to “CanBus and Modbus communication with OCS“ section for further information.

Low pressure sensor connection

Communication connections In the case of parallel mounting, CAN-Bus cables must link compressors together in order to allow data exchange between compressors.

Connectors are 4 pole 3.5 mm pitch terminal blocks.

In parallel mounting, only one HP transmitter and one LP transmitter are needed per compressor assembly, connected to only one of the OCS, for the complete system.

If needed, the Modbus connection is to be done with a 3 pole 3.5 mm pitch terminal block

(supplied on the OCS).

Shielded cables must be used for CAN-Bus and

Modbus connections.

General wiring information

A minimum distance of 10 cm between power supply cables and communication cables must be observed in order to avoid electronic interferences and disturbances.

Accessory CAN-Bus cables are available for tandem and trio assemblies (refer to accessories list for code numbers).

Data readings and recovering can be done thanks to a MMIGRS and a MMIMYK connected on the RJ11 female connection on the OCS (refer to section ”Data Management“).

MMIGRS and MMIMYK accessories are available

(refer to accessories list for code numbers).

The wiring diagrams below are examples for a safe and reliable compressor wiring. In case an alternative wiring logic is chosen, it is imperative to respect the following rules: the tripping condition is back to normal and the safety switch is closed again. This applies to the LP safety switch, the HP safety switch, the discharge gas thermostat and the motor safety thermostat.

M1 M2 contact on OCS must be used for compressor protection (do not use Bus signal).

When a safety switch trips, the compressor must stop immediately and must not re-start until

In specific situations, such as winter start operation, an eventual LP control for pumpdown cycles may be temporarily bypassed to allow the system to build pressure. But it remains

FRCC.PC.021.A5.02

15

Application Guidelines Electrical data, connections and wiring

mandatory for compressor protection to apply an LP safety switch. The LP safety switch must never be bypassed.

Pressure settings for the LP and HP safety switch and pump-down listed in table from section

”Low pressure“.

When ever possible (ie. PLC control), it is recommended to limit the possibilities of compressor auto restart to less than 3 to 5 times during a period of 12 hours when caused by motor protection or LP safety switch tripping.

This control must be managed as a manual reset device.

Suggested wiring diagram

Control circuit

LP

A1

A3

A2

LPS

OCS

M1 M2

S M

KS

A1

A3

A2

LPS

OCS

M1 M2

S

Wiring diagram without pump down cycle

Wiring diagram with pump-down cycle

Legend

Electrical box knock-out dimensions

IP rating

Electrical box temperature

Fuses ...........................................................................................................F1

Compressor contactor ........................................................................ KM

Control relay ............................................................................................ KA

Safety lock out relay ..............................................................................KS

Optional short cycle timer (3 min) ............................................. 180 s

External overload protection .............................................................F2

Pump-down pressure switch .............................................................LP

High pressure safety switch ...............................................................HP

Control device ........................................................................................ TH

Liquid line solenoid valve ............................................................... LLSV

Fused disconnect ..................................................................................Q1

Compressor motor ..................................................................................M

Thermistor chain ....................................................................................... S

Safety pressure switch ........................................................................LPS

Six different knockouts are available for power supply or accessories connections.

One double knockout for power supply:

Ø 43.7mm/1.72" or Ø 34.5mm/1.36"

Two double knockouts for accessories:

Ø 25.4mm/1" or Ø 20mm/0.78"

Two double knockouts for accessories:

Ø 22.5mm/0.88" or Ø 16.5mm/0.65"

One triple knockout for power supply:

Ø40.5mm/1.59" or Ø32.5mm/1.27" or Ø 5.4mm/1"

The compressor terminal box according to IEC529 is IP54 for all models when correctly sized IP54 rated cable glands are used.

First numeral, level of protection against contact and foreign objects

5 - Dust protected

Second numeral, level of protection against water

4 - Protection against water splashing

The temperature inside the terminal box must not exceed 65°C. Above 65°C, the OCS may not operate properly. Any compressor damaged related to this will not be covered by Danfoss warranty.

that the temperature around the compressor and in the terminal box rise too much. The installation of ventilation on the enclosure panels may be necessary.

Consequently, if the compressor is installed in an enclosure, precautions must be taken to avoid

In the same manner, cables must be selected in a way to insure that terminal box temperature does not exceed 65°C.

16 FRCC.PC.021.A5.02

Application Guidelines

Approvals and certificates

Approval and certifications

PSH scroll compressors comply with the following approvals and certificates.

CE 0062 or CE 0038 or CE0871

(European Directive)

UL

(Underwriters Laboratories)

Other approvals / certificates

Certificates are listed on the product datasheets: http://www.danfoss.com/odsg

All PSH models

All 60 Hz PSH models

Contact Danfoss

Pressure equipment

directive 2014/68/EU Products

Refrigerating fluids

Category PED

Evaluation module

Maximum / Minimum temperature - Ts

Maximum allowable pressure (LP side) - Ps

Declaration of conformity

PSH051

Group 2

II

D1

-35°C < Ts < 52°C

31.1 bar(g)

PSH064

Group 2

II

D1

-35°C < Ts < 51°C

30.2 bar(g)

Contact Danfoss

PSH077

Group 2

III

H

-35°C < Ts < 51°C

30.2 bar(g)

Internal free volume

PSH051

PSH064

PSH077

Products Internal free volume without oil (litre)

31.0

32.6

34.3

Low voltage directive

2014/35/EU Products

Declaration of conformity

PSH051 to 077

Contact Danfoss

Machines directive

2006/42/EC

Electromagnetic compatibility directive

2014/30/EU

Products

Manufacturer's declaration of incorporation

PSH051 to 077

Contact Danfoss

PSH compressors with their OCS are in conformance with the requirements of the following standards:

• EN61000-6-2: immunity for industrial environments

• EN61000-6-4: emission standard for industrial environments

FRCC.PC.021.A5.02

17

Application Guidelines

Refrigerant and lubricants

R410A

POE oil

Motor supply

Compressor ambient temperature

High ambient temperature

Low ambient temperature

Operating conditions

PSH compressors are to be used with R410A refrigerant, with polyolester oil.

• R410A’s superior thermodynamical properties compared to R22 and R407C refrigerants allow for today’s massive – and necessary – switch to high efficiency systems.

• Zero Ozone Depletion Potential (ODP): R410A doesn’t harm the ozone layer.

• Global warming potential (GWP): R410A shows a relatively high warming potential. However, the GWP index denotes direct warming effect, which is relevant only in case of release to the atmosphere.

A more accurate index is T.E.W.I., for Total

Equivalent Warming Impact, which takes into account indirect contributions due to running energy costs.

• Because of the higher system efficiency it allows to achieve, R410A is in this regard the best refrigerant.

• As a near-azeotropic mixture, refrigerant

R410A behaves like an homogeneous substance, whereas other zeotropic mixtures such as

R407C and other blends suffer a temperature glide during phase change that lessens thermal efficiency and makes them difficult to transfer from a container to another.

• Reduced refrigerant mass flow, permitted by a higher heat capacity, induce a lower sound level of the installation as well as more compact and lighter systems.

Polyolester oil (POE) is miscible with HFC's

(while mineral oil is not), but has to be evaluated regarding lubrication ability in compressors. POE oil has better thermal stability than refrigerant mineral oil.

POE is more hygroscopic and also holds moisture tighter than mineral oil. It also chemically reacts with water leading to acid and alcohol formation.

PSH scroll compressors can be operated at nominal voltages as indicated in the section

”Motor voltage“. Under-voltage and over-voltage operation is allowed within the indicated voltage ranges. In case of risk of under-voltage operation, special attention must be paid to current draw.

PSH compressors can be applied from -35°C to 51°C ambient temperature, when charged with refrigerant. The compressors are designed

In case of enclosed fitting and high ambient temperature it’s recommend to check the temperature of power wires and conformity to their insulation specification. In case of safe tripping by the internal compressor overload

Although the compressor itself can withstand low ambient temperature, the system may require specific design features to ensure safe as 100% suction gas cooled without need for additional fan cooling. Ambient temperature has very little effect on the compressor performance.

protection the compressor must cool down before the overload will reset. A high ambient temperature can strongly delay this cool-down process.

and reliable operation. See section ”Specific application recommendations“.

18 FRCC.PC.021.A5.02

Application Guidelines

Compressor protection

Operating conditions

2 status LEDs are present on OCS:

LED1 (red) displays the board general status

LED2 (yellow) displays the motor protection status

LED 1 Status display





Overheating/overloading protection

LED1 displays the board general status with the following blinking codes

Blinking sequence Status

Continuous on

Slow blinking

1.5secON/1secOFF

Fast blinking

0.5secON/0.5secOFF

OCS powered and stable

Warning without requirement for immediate action.

ALARM , requires maintenance intervention

Reset

NA

Come back to stable status by automatic or manual reset.

Come back to stable status by specialist intervention

LED 2 displays the motor protection status.

Compressor models PSH051-064-077 are delivered with a pre installed motor protection.

This device provides efficient and reliable protection against overheating, overloading as well as phase loss/reversal.

The motor protection is effective thanks to PTC sensors embedded in the motor winding and

OCS control. The close contact between sensors and windings ensures a very low level of thermal inertia.

If any thermistor exceeds its response temperature, its resistance increases above the trip level (4,500 Ω) and the output relay then trips

– i.e. contacts M1-M2 are open.

The motor temperature is constantly measured by a PTC thermistor loop connected to the OCS.

After cooling below the response temperature

(resistance < 2,750 Ω), a 5 minutes time delay is activated. After this delay has elapsed, the relay is once again pulled in – i.e. contacts M1-M2 are closed. The time delay may be cancelled by means of resetting the mains.

LED 2 Status display Blinking sequence

 Continuous on

0.1secON/ 0.3secOFF

for 5 min 0.1secON/0,7secOFF.

Status

Ready for starting

ALARM 22 : Motor overheating

ACTION : STOP COMPRESSOR

RESTART : 5min Delay after motor cooling.

FRCC.PC.021.A5.02

19

Application Guidelines

Phase sequence and reverse rotation protection

LED 2 Status display



Operating conditions

Use a phase meter to establish the phase orders and connect line phases L1, L2 and L3 to terminals T1, T2 and T3, respectively. The compressor will only operate properly in a single direction, and the motor is wound so that if the connections are correct, the rotation will also be correct.

OCS provides protection against phase reversal and phase loss at start-up.

Apply the recommended wiring diagrams from the section ”Suggested wiring diagram logic“.

The circuit should be thoroughly checked in order to determine the cause of the phase problem before re-energizing the control circuit.

The phase sequencing and phase loss monitoring functions are active during a 5 seconds window 1 second after compressor start-up (power on L1-L2-L3)

0.2secON/0.2secOFF

0.2secON/0.4secOFF

0.5secON/0.5secOFF

Blinking sequence Status

ALARM 25 :Phase reverse error

ACTION : STOP COMPRESSOR

RESTART : Come back to stable status by manual reset

ALARM 24 :Phase loss error

ACTION : STOP COMPRESSOR

RESTART : Come back to stable status by manual reset

Application envelope

The operating envelope for PSH scroll compressors is given in the figure below, where the condensing and evaporating temperatures represent the range for steady-state operation.

The operating limits serve to define the envelope within which reliable operations of the compressor are guaranteed:

• Maximum discharge gas temperature:

+140°C (measured by DGT sensor),

• A suction superheat below 5 K is not allowed due to the risk of liquid flood back,

• Maximum suction superheat of 20K

• A subcooling above 5K is recommended to ensure proper liquid injection.

• Minimum and maximum evaporating and condensing temperatures as per the operating envelopes.

50

40

30

20

70

60

10

0

-10

-35 -30 -25 -20 -15 -10 -5 0 5

Evaporating temperature (°C)

10 15 20 25

20 FRCC.PC.021.A5.02

Application Guidelines

Transient conditions

Operating conditions

The OCS controls the compressor operation by monitoring high pressure, low pressure and discharge temperature.

Alarms are displayed when the compressor exceeds the limits and the control circuit M1-M2 is opened if normal operation is not recovered within predefined delays (see table below).

Compressor start up is allowed only in starting areas 1, 2.3 and 3.

During start-up or defrost, the compressor may operate outside this envelope for short periods.

Transient conditions (areas 2.1, 2.2, 2.3, 3) are allowed and also monitored by the OCS (see table below for details).

70

45

40

35

30

25

20

15

10

65

60

55

50

4

2.1

2.2

5

0

-5

-10

-15

-20

-25

-40 -35 -30 -25 -20 -15 -10

1

2.3

Area 1: continuous running SH5K to 20K

Area 2.3: 3 min. maximum

Area 3: 3 min. maximum

Area 1+2.3+3: start/restart map.

-5 0 5 10

Evaporating temperature (°C)

15 20

Area 2.1: 31 s maximum

Area 2.2: 31 s maximum

Discharge pressure warning

25

3

30 35

4

40

Area 4: outside map

45 50 55

FRCC.PC.021.A5.02

21

Application Guidelines

Alarms displayed by OCS and related taken actions

Operating conditions

Conditions ACTION before condition runs out Delay ACTION once condition has run out

Cumulated time

ACTION once the boundary condition has run out

Area 1 no action ∞ no action ∞ NA

Area 2.1

Area 2.2

Area 2.3

Area 3

Area 4

Area 3

AND

[power switched on]

WARNING W30 : ”low suction pressure, stop in 31 sec“

WARNING W46 : ”High compression ratio, stop in 31sec“

WARNING W33 difference, stop in 3min“

WARNING W50

: ”Low pressure

: ”Compressor back to starting area, stop in 3 min“

31s

31s

3 min

3 min

ALARM A44 : ”low suction pressure, compressor stopped“

ACTION : stop the compressor

RESTART : back to normal range then automatic reset and manual reset after 4 repeated occurrences in 24h.

ALARM A31 : ”High compression ratio, compressor stopped“

ACTION : stop the compressor

RESTART : back to normal range then automatic reset and manual reset after 4 repeated occurrences in 24h.

ALARM A34 : ”Low pressure difference, compressor stopped“

ACTION : stop the compressor

RESTART : value back to normal range then automatic reset and manual reset after 4 repeated occurences in 24h.

ALARM A36 : ”compressor outside envelope, compressor stopped“

ACTION : stop the compressor

RESTART : back to normal range then automatic reset and manual reset after 4 repeated occurrences in 24h.

250h

336h

2100h

ALARM A36 : ”compressor outside envelope, compressor stopped“

ACTION: STOP THE COMPRESSOR

RESTART: back to normal range then automatic reset and manual reset after

4 repeated occurrences in 24h.

0s no action 0s

WARNING W38 ”compressor start outside envelope, stop in 3min“

UNIT ACTION: GO TO THE

OPERATING ENVELOPE .

3 min

ALARM A39 : ”compressor start outside envelope, compressor stopped“

ACTION : stop the compressor

RESTART : back to normal range then automatic reset and manual reset after 2 repeated occurrences in 1h.

7500h

WARNING W45 : ”250h low suction pressure. Max duration exceeded“

WARNING W32 : ”336h high compression ratio. Max duration exceeded“

WARNING W35 : ”2100h low pressure difference. Max. duration exceeded“

NA

NA

WARNING W40 : ”7500h starting mode-Max duration exceeded“

Area 4

AND

[power switched on]

ALARM A41 ”no start because pressure out of range“

ACTION :no start

0s no start 0s no start

P disch >

41.7bar g

WARNING W47 : ”Discharge pressure close to HPS limit“

ACTION : UNLOAD THE UNIT

∞ no action ∞ NA

22 FRCC.PC.021.A5.02

Application Guidelines

Pressure transmitter accuracy and range

Liquid injection

Filter drier

Operating conditions

The OCS functionalities use the evaporating pressure and condensing pressure signals, and may be directly impacted by pressure transmitters accuracy.

To fully benefit from OCS functionalities

(reliability features, overall application envelope with transient conditions) it is recommended to use ratiometric pressure transmitters (0-5V) with:

PSH compressors require liquid injection to maintain sufficiently low discharge gas temperature within the entire operating envelope. Liquid refrigerant is directly injected into the scroll set.

PSH compressors are provided with a liquid injection connection. Liquid pick-up has to be done at the bottom side of the liquid line piping and downstream the filter drier .

• accuracy lower than ±1.15bar a on high pressure side, range 0-50bar a

• accuracy lower than ±0.3bar a on low pressure side, range 0-35bar a.

High pressure and low pressure transmitter

(sensor + connector) accessories are available

(refer to accessories list for code numbers).

The Liquid Injection Valve regulates the liquid mass flow rate according to the discharge temperature.

Liquid injection is active only for evaporating temperature below 0°C and discharge temperature above 140°C.

A minimum 5K subcooling is necessary to ensure correct liquid injection.

In(P)

Pc

Pi

Discharge temperature protection

Po h (kJ/kg)

The Liquid Injection Valve (LIV) is an ETS6 stepper valve. This valve is closed when the compressors is idle.

Liquid injection valve accessory is available (refer to accessories list for code numbers).

An additional solenoid valve has to be installed in case of power shortage to prevent from liquid to come back to the compressor. Only one solenoid valve per unit is required. This solenoid valve must be a normally closed (NC) valve and a direct operation valve.

If discharge gas temperature exceeds 150°C and in case of liquid injection issue (not enough sub-cooling for example), the OCS will display a warning. The unit has 5 minutes to decrease the temperature below 150°C otherwise control circuit M1-M2 will be opened.

If discharge gas temperature reaches 160°C, the control circuit M1-M2 will open.

Discharge gas temperature sensor accessory

(sensor + cable) is available (refer to accessories list for code numbers).

Conditions

150°C ≥ discharge temp. < 160°C

WARNING W27 : ”max. discharge temp., stop in 5min“

Discharge temp.

≥ 160°C

ACTION before condition running out

ALARM A28 : ”max. discharge temp. , compressor stopped“

Delay

5min.

0s

ACTION once condition has running out

ALARM A28 : ”max. discharge temp. , compressor stopped“

ACTION : stop the compressor

RESTART : back to normal range

(≤145°C) then automatic reset and manual reset after 4 repeated occurrences in 24h.

Cumulated time

ACTION once the boundary condition has running out

1500h

WARNING W29 : ”1500h above max. disch. temp., change oil“ no action 0s NA

FRCC.PC.021.A5.02

23

Application Guidelines

Malfunction protection

Component

Operating conditions

The OCS also provides information about below listed malfunctions.

Maintenance operations should include an OCS diagnosis analysis, in order to check the warnings and alarms status history provided by the OCS.

Detection Criteria(s) Alarm Action

Crankcase heater

Resistance out of operating range

OR

Current out of range

WARNING W43 : “Crankcase heater dysfunction”.

No action

Discharge Temperature sensor

(1 on each compressor)

Resistance out of operating temperature range

ALARM A42 : “Discharge

Temperature sensor error”

STOP the compressor

Pressure transducers LP

(1 on compressor OR via comm.

bus)

Voltage out of sensor operating pressure range [0,1;4,9]V

OR broadcasting not available via CAN-Bus

ALARM A15 : “Low Pressure transmitter error”.

Pressure transducers HP

(1 on compressor OR via comm.

bus)

Voltage out of sensor operating pressure range [0,1;4,9]V

OR broadcasting not available via CAN-Bus

ALARM A16 : “High Pressure transmitter error”.

Auto search for alternative sensor on the manifold, else

STOP the compressor.

RESTART sequence value back to normal range, then automatic reset.

Auto search for alternative sensor on the manifold, else

STOP the compressor.

RESTART sequence value back to normal range, then automatic reset.

Motor PTC Resistance out of operating range

ALARM A20 : “Motor PTC out of order”.

STOP the compressor (open Switch).

RESTART sequence value back to normal range, then automatic reset.

CAN-Bus

Compressor1  Compressor2 or Mainboard

Timeout 10s

WARNING W21 :

“Communication bus disabled” No action

Modbus bus

Compressor1  MAINBOARD Timeout 1min

WARNING W21 :

“Communication bus disabled” No action

Liquid Injection Valve Coil Resistance out of operating range

ALARM A48 : 

"Liquid Injection valve error”.

STOP the compressor (open Switch).

High and low pressure protection

The OCS will display alarms when the compressor is running outside the operating envelope. The compressor will be stopped when it does not come back to normal running conditions within a defined delay.

24 FRCC.PC.021.A5.02

Application Guidelines

High pressure

Operating conditions

A high-pressure (HP) safety switch is required to shut down the compressor should the discharge pressure exceed the values shown in the table section ”System pressure test“. The high-pressure switch can be set to lower values depending on the application and ambient conditions. The HP switch must either be placed in a lockout circuit or consist of a manual reset device to prevent cycling around the high-pressure limit. If a discharge valve is used, the HP switch must be connected to the service valve gauge port, which can not be isolated.

High pressure safety switch test

High-pressure safety switch shall be tested on the unit and this test may be in conflict with OCS reliability protection in the case of HP switch setting is higher than “Pdisch_limit” (45.7bar(a)).

During this test, the alarm A36 and consecutively the opening of M1-M2 switch shall not be considered to validate the HP switch setting.

Internal pressure relief valve The PSH077 incorporates an internal relief valve set to open between the internal high and low pressure sides of the compressor when the pressure differential between the discharge and suction pressures surpasses 42.4 to 49 bar. This safety feature prevents the compressor from developing dangerously high pressures should the high pressure cut-out, for whatever reason, fail to shut down the compressor.

Low pressure

HP

LP

Relief valve

Deep vacuum operations of a scroll compressor can cause internal electrical arcing and scroll instability. Danfoss PSH Scroll compressors exhibit high volumetric efficiency and may draw very low vacuum levels, which could induce such a problem. Low back pressure protection is integrated in OCS function, so no additional protection is needed.

LP switch settings for pump-down cycles with automatic reset are listed in the table below.

Pressure settings

Working pressure range high side

Working pressure range low side

Maximum high pressure safety switch setting

Minimum low pressure pump-down switch setting * bar (g) bar (g) bar (g) bar (g)

* Recommended pump-down switch settings: 1.5 bar below nominal evap. pressure with minimum of 1.7 bar(g)

R410A

5.8 - 44.7

1.7 - 13.4

46.1

1.7

The low pressure pump down switch setting must always be within the operating envelope, for example 1.7 bar for R410A. The compressor can be operated full time under such condition.

FRCC.PC.021.A5.02

25

Application Guidelines

Cycle rate limit

Operating conditions

Danfoss recommends a restart delay timer to limit compressor cycling. The timer prevents reverse compressor rotation, which may occur during brief power interruptions. The system must be designed in a way that guarantees a minimum compressor running time of 2 minutes so as to provide for sufficient motor cooling after start-up along with proper oil return. Note that the oil return may vary since it depends upon system design. There must be no more than 12 starts per hour, a number higher than 12

A1

TH

A2 reduces the service life of the motor-compressor unit. A three-minute (180-sec) time out is recommended.

~

KA

TH

A2 A1

180 s

A3

T T

KA

~

Please contact Danfoss Technical Support for any deviation from this guideline.

26 FRCC.PC.021.A5.02

Application Guidelines

Data storage displayed by OCS

Traceability data

Data management

The OCS is able to record data for operating checking, maintenance, inspection. Data can be displayed by Modbus, CAN-Bus or MMIMYK/

MMIGRS interfaces.

In order to ensure traceability the information below are pre-set

• compressor serial number CSN

• Software version

There are 4 types of data available:

• Traceability data

• Operation parameter recording

• Alarms, warnings and events

• Event counter

Alarms regarding motor protection and operating envelope monitoring are displayed.

• Board reference

• Board serial number

• Temperature unit (in °C by default)

• Pressure unit

Operation parameter recording

The following parameters are recorded for the 3 last years:

Parameters

Condensing pressure

Evaporating pressure

Discharge temperature

Surface sump heater

Clock

Liquid injection valve opening degree

Compressor On

Abbreviation

Pc

Pe

DGT

SSH

NA

OD

Cpr

Value frame

00,0

00,0

000

0 for OFF - 1for ON

YY/MM/

DD_HH:MM:SS

00,0

0 for OFF – 1 for ON

Indicative Range

0-50

0-30

-35 / +170°C

0-1

NA

0-100

0-1

Unit

Bar or gauge

Bar or gauge

°C

NA

NA

% PID regulator Data

(valve opening)

NA

Alarms, warning and events

Event counter

MMIMYK and MMIGRS

Electronic controllers

A buffer storage for alarms, warning and events will follow First-In First-Out (FIFO) rules. A total capacity of 3000 lines is available.

A definite storage file running as a counter will record the following data:

• Each alarm

• Each event

• Surface sump heater on/off

• Compressor on/off

• Liquid injection valve closing

The storage period is minimum 3 years for each data.

MMIGRS and MMIMYK are electronic user interfaces used to communicate with OCS.

MMIGRS is a remote LCD screen display. It allows reading of variable data and parameters

(instantaneous values).

MMIGRS address is NodeID 126 by default.

MMIGRS panel mounting accessory is available

(refer to accessories list for code number).

For MMIGRS instructions, see document:

DKRCC.PI.RJO.C2.1U

FRCC.PC.021.A5.02

27

Application Guidelines

Data read-out

Data storage recovery

Data management

MMIMYK can be used to download programs on

OCS and allows data storage recovery.

MMIMYK address is NodeID 127 by default.

MMIMYK accessory is available (refer to accessories list for code number).

For MMIMYK instructions, see document:

DKRCC.PI.RJO.B1.1U

RJ11 connection cable is available as accessories.

Refer to code number in section ”Accessories“.

Data can be read by connecting MMIGRS to the

OCS via RJ11 cable. Select the address of the compressor for data reading. Then:

• “Status/Read out” menu : Parameters can be read on the screen.

• “Alarms/Active alarms” menu displays active alarms.

Both MMIGRS and MMIMYK are needed to recover data

• “Alarms/Alarm log” menu displays 40 last alarms and warnings, since last OCS power-off.

• “Service” menu displays various information about real time clock software revision, bios revision, OCS serial number, compressor serial number.

• MMIGRS initiates data storage transfer:

Connect MMIGRS to OCS via RJ11 cable.

“Parameter/General/Set up/log transmit” menu allows to choose between different types of data transfer and to transfer data from OCS to a SD card.

Data transfer type

L01

L12

L24

EVNT

Disconnect MMIGRS

Log frequency

Each 5 sec.

Each 20 sec.

Each 5 min.

Each time alarm or warning occur or reset

File name

005FFF01

005FFF02

005FFF03

005FFF03

• MMIMYK recovers data: Connect MMIMYK to the OCS via RJ11 cable. Power-off the OCS.

Power-on it. Data will be transferred to a file in

SD card. This file can be translated in .csv file thanks to a specific application.

Please contact Danfoss Technical Support for any additional information.

28 FRCC.PC.021.A5.02

Application Guidelines

General hardware network and communication protocol

Compressor address set-up for CAN-Bus and

Modbus

Dipswitches

CAN-Bus and Modbus RS485 Communication

CAN-Bus and RS485 hardware network must follow the recommendations described in the document DKRCC.PS.RIO.F1.02.

CAN-Bus and Modbus RS485 Communication protocol parameters are as follow: a. CANOPEN: nodeID: 1, baudrate: 50K

Compressor NodeID must be changed to have individual address. There are two ways to change the compressor address: b. Modbus RS485: ID: none, baudrate: 9600, databits: 8, partity: NONE, stop bits: 1.

• Dipswitches on OCS (recommended).

• NodeID from MMIMYK

Dipswitches on OCS are set at 0 by default and have to be changed following the recommendation below:

Before changing the compressor address on dipswitches, the OCS must be powered-off.

A valid NodeID has to be set as binary code.

The 4 first dipswitches (1 to 4) are for compressor identifiant, the 3 last dipswitches (5 to 7) are for circuit/rack identification.

Below tables give examples.

The dipswitch address is read as NodeID at power-up and changed if address is valid (1 to

125).

1

Compressor

2 3

Dipswitches on OCS

4 5 6

Circuit

7 8 address default

Example 1: 1 circuit, 3 compressors

Compressor 1

1

Compressor 2

1

Compressor 3

1 1

Example 2: 2 circuits, 2 compressors per circuit

Compressor 1

1

Compressor 2

1

Circuit A

1

Circuit A

1

Compressor 1

1

Compressor 2

1

Circuit B

Circuit B

Example 3: 2 circuits, 3 compressors per circuit

Compressor 1 Circuit A

1

Compressor 2

Compressor 3

1

Compressor 1

1

1

1

Compressor 2

Compressor 3

1

1 1

1

Circuit A

1

Circuit A

1

Circuit B

Circuit B

Circuit B

1

1

1

1

1

33

34

35

17

18

19

33

34

17

18

1

2

3

FRCC.PC.021.A5.02

29

Application Guidelines

NodeID

CAN-Bus and Modbus communication with OCS

CAN-Bus and Modbus RS485 Communication

NodeID can be changed with a MMIMYK connected to OCS with a RJ11 cable. CAN-Bus must be deconnected and NodeID has to be set separately on each compressor.

Check that MMIMYK communicates properly with the compressor OCS.

NodeID can be changed through menu Program/

Config Node/NodeID.

If NodeID is changed by MMIMYK, the dipswitch setting on OCS will not show the active NodeID.

The CAN-Bus connection will allow:

• sharing LP and HP pressure sensors in the rack

• Surface sump heater (SSH) consumption management

Disch. temp.

The Modbus connection will allows:

• sharing LP and HP pressure sensors with the unit

• identification of compressor address for diagnosis.

• alarm reading

Disch. temp.

HP pressure

M1-M2: safety and reliability switch

Disch. temp.

Unit control board panel MODBUS

(optional)

OCS OCS OCS

CAN CAN

LIV LIV LIV

SSH SSH

LP pressure

SSH

Pressure signals must be entered to OCS. There are 2 options:

1. The preferred option is to connect the pressure transmitters on one of the OCS of the compressors rack. This ensures a fast reactivity regarding compressors protection, with a polling time of 1 second.

The other OCS of the compressors rack will receive pressure information via broadcasting through the CAN connection. In this case, the unit controller can access to the pressure information through Modbus:

• Unit type is Bar absolute

• scaled x10000 (120000 equals 12.0 bar absolute)

• valid range 0.0 – 200.0 Bar absolute

2. The pressure signals can also be transmitted from the unit controller through Modbus communication.

Signal

Pc

Pe

Register (long)

Hex.

Dec.

0x1F4

0x1F6

500

502

In this case, the LP and HP pressures should be written in the following registers of the OCS connected to the unit.

Hex.

High word

Dec.

0x1F4

0x1F6

500

502

Hex.

Low word

Dec.

0x1F5

0x1F7

501

503

The signal content is as in following exemple:

Pc = 23.5678 bar absolute

Scaled value: 23.5678*10000 = 235678 (same in hexadecimal form: 0x0003989E)

Low word: 0x989E (decimal value = 39070)

High word: 0x0003 (decimal value = 3)

This OCS will broadcast these pressures to all the other OCS of the compressor rack. A transmission period of max 2 seconds is recommended.

OCS will detect Modbus communication timeout after 3 seconds. In this case:

• If a backup transmitter is connected to another OCS board, then the local signal will be used and this backup transmitter will start broadcasting.

• If no backup transmitter is present in the rack, all compressors will be stopped.

30 FRCC.PC.021.A5.02

Application Guidelines

Measurements

CAN-Bus and Modbus RS485 Communication

Description:

AI_Pc_x10

AI_Pe_x10

Tc_x10

Te_x10

Liq_Ctrl_ref_x10

Liq_Ctrl_error_x10

Liq_valve_OD_x10

Map_pos

MaxDischargeTemp_log

MinSucPressure__log

HighPressureRatio_log

LowPressureDiff_log

MaxTimeStartMode_log

DO_Start

DO_SurfaceSumpHeater

DI_status

PTC_resistance_x4

SSH_mA_V

ComprRunStatus

Variable

Note

Measured condensing pressure

Measured evaporating pressure

Calculated condensing temperature

Calculated evaporatinging temperature

Injection control temperature

Injection control error

Valve opening degree %

Possition on operating envelope area

Max. discharge temperature time counter

Min. suction pressure time counter

High pressure ratio time counter

Low pressuredifference time counter

Max. time start mode time counter

Relay output status for Contactor switch

Relay output status for Sumpheater bit 6: DI_SSH_failure bit 5: DI_wrong_phase_sequence bit 4: - not used bit 3: - not used bit 2: DI_Phase_loss bit 1: DI_compr_Stopped bit 0: DI_PTC_alarm

PTC measurement [ohm]

(when compressor is off)

SSH measured value

SSH ON: [mA],

SSH OFF: [Volt]

0: stopped 1: running

Register

0x3908

0x3909

0x390A

0x390B

0x390C

0x390D

0x390E

0x390F

0x3910

Hex

0x3900

0x3901

0x3902

0x3903

0x3906

0x3907

14600

14601

14602

14603

14604

14605

14606

14607

14608

Dec

14592

14593

14594

14595

14598

14599

0x3912 14610

0x3913 14611

0x3914

0x3915

14612

14613

FRCC.PC.021.A5.02

31

Application Guidelines

Alarms and warning

CAN-Bus and Modbus RS485 Communication

Variable

Description Note

Warning W09 W09 Wait 6hrs SSH on or jog before start

Warning W13 W13 Cps start before 6hrs SSH on

Alarm A15 A15 Low Pressure transmitter error

Alarm A16

Alarm A20

A16 High Pressure transmitter error

A20 PTC is open

Warning W21 W21 Communication bus disabled

Alarm A22

Alarm A24

A22 Compressor overloaded/PTC tripping

A24 Phase loss sequence

Alarm A25 A25 Wrong phase sequence

Warning W26 W26 OCS excessive temperature

Warning W27 W27 Max discharge temp. , stop in 5 min

Alarm A28 A28 Max discharge temp. , cpr stopped

Warning W29 W29 1500h above max disch.temp. - change oil

Warning W30 W30 Low suction pressure, stop in 31 sec

Alarm A31 A31 High compression ratio, cpr stopped

Warning W32 W32 336h High compres. ratio, Max duration ex

Warning W33 W33 Low pressure difference, stop in 3 min

Alarm A34 A34 Low pressure difference, cpr stopped

Warning W35 W35 2100h Low pressure diff., Max duration ex

Alarm A36 A36 Compressor outside envelop, cpr stopped

Warning W38 W38 Cpr start outside envelop, stop in 3 min

Alarm A39 A39 Cpr start outside envelop, cpr stopped

Warning W40 W40 7500 h outside start envelop-duration exed

Alarm A41

Alarm A42

A41 No start because pressure outside range

A42 Discharge Temperature sensor error

Warning W43 W43 Crankcase heater dysfunction

Alarm A44 A44 low suction pressure, cpr stopped

Warning W45 W45 250h low suction pressure-max duration ex

Warning W46 W46 High compression ratio, stop in 31 sec

Warning W47 W47 Disch. Pressure close to HPS limit

Alarm A48 A48 Liquid Injection Coil error

Warning W50 W50 Comp, back to starting area, stop in 3 min

0x3219

0x321A

0x321B

0x321C

0x321D

0x321E

0x321F

0x3220

0x3221

0x3222

0x3223

0x3224

0x3226

0x3227

0x3228

0x3229

0x322A

0x322B

0x322C

0x322D

0x322E

0x322F

0x3230

0x3202

Hex

0x3207

Register

Dec.

12807

0x320D

0x320F

0x3210

0x3214

0x3215

0x3216

0x3218

12813

12815

12816

12820

12821

12822

12824

12843

12844

12845

12846

12847

12848

12802

12825

12826

12827

12828

12829

12830

12831

12832

12833

12834

12835

12836

12838

12839

12840

12841

12842

32 FRCC.PC.021.A5.02

Application Guidelines

General

Essential piping design considerations

Suction lines

Discharge lines

System design recommendations

Successful application of scroll compressors is dependent on careful selection of the compressor for the application. If the compressor is not correct for the system, it will operate beyond the limits given in this manual. Poor performance, reduced reliability, or both may result.

The working pressure in systems with R410A is about 60% higher than in systems with R22 or

R407C. Consequently, all system components and piping must be designed for this higher pressure level.

compared to R22 / R407C systems. Take care not to create too high pressure drops or since in R410A systems the negative impact of high pressure drops on the system efficiency is stronger than in R22/R407C systems.

Proper piping practices should be employed to ensure adequate oil return, even under minimum load conditions with special consideration given to the size and slope of the tubing coming from the evaporator. Tubing returns from the evaporator should be designed so as not to trap oil and to prevent oil and refrigerant migration back to the compressor during off-cycles.

In systems with R410A, the refrigerant mass flow will be lower compared to R22/R407C systems. To maintain acceptable pressure drops and acceptable minimum gas velocities, the refrigerant piping must be reduced in size

Piping should be designed with adequate three-dimensional flexibility. It should not be in contact with the surrounding structure, unless a proper tubing mount has been installed.

This protection proves necessary to avoid excess vibration, which can ultimately result in connection or tube failure due to fatigue or wear from abrasion. Aside from tubing and connection damage, excess vibration may be transmitted to the surrounding structure and generate an unacceptable noise level within that structure as well. For more information on noise and vibration, see the section on: ”Sound and vibration management“.

If the evaporator lies above the compressor, as is often the case in split or remote condenser systems, the addition of a pump-down cycle is strongly recommended. If a pump-down cycle were to be omitted, the suction line must have a loop at the evaporator outlet to prevent refrigerant from draining into the compressor during off-cycles.

If the evaporator were situated below the compressor, the suction riser must be trapped so as to prevent liquid refrigerant from collecting at the outlet of the evaporator while the system is idle, which would mislead the expansion valve’s sensor (thermal bulb) at start-up.

When the condenser is mounted at a higher position than the compressor, a suitably sized

”U“-shaped trap close to the compressor is necessary to prevent oil leaving the compressor from draining back to the discharge side of the compressor during off cycle. The upper loop also helps avoid condensed liquid refrigerant from draining back to the compressor when stopped.

U-trap

0.5% slope

4m/s or more

To condenser

HP

LP max. 4m max. 4m

U-trap, as short as possible

8 to 12m/s

Evaporator

0.5% slope

4m/s or more

U trap, as short as possible

U Trap

Upper loop

LP

HP

Condenser

3D flexibility

FRCC.PC.021.A5.02

33

Application Guidelines

Heat exchangers

Off-cycle migration

Sump heater

System design recommendations

To obtain optimum efficiency of the complete refrigerant system, optimised R410A heat exchangers must be used. R410A refrigerant has good heat transfer properties: it is worthwhile designing specific heat exchangers to gain in size and efficiency.

A sub-cooler circuit in the condenser that creates high sub cooling will increase efficiency at high condensing pressure. In R410A systems the positive effect of sub cooling on system efficiency will be significantly larger than in R22/

R407C systems.

An evaporator with optimised R410A distributor and circuit will give correct superheat at outlet and optimal use of the exchange surface. This is critical for plate evaporators that have generally a shorter circuit and a lower volume than shell & tubes and air cooled coils.

For all evaporator types a special care is required for superheat control leaving the evaporator and oil return.

Furthermore, for good operation of the expansion device and to maintain good efficiency in the evaporator it is important to have a high degree of liquid sub cooling. Without adequate sub cooling, flash gas will be formed at the expansion device resulting in a high degree of vapour at the evaporator inlet leading to low efficiency.

Off-cycle refrigerant migration is likely to occur when the compressor is located at the coldest part of the installation, when the system uses a bleed-type expansion device, or if liquid is allowed to migrate from the evaporator into the compressor sump by gravity. If too much liquid refrigerant accumulates in the sump it will saturate the oil and lead to a flooded start: when the compressor starts running again, the refrigerant evaporates abruptly under the sudden decrease of the bottom shell pressure, causing the oil to foam. In extreme situations, this might result in liquid slugging (liquid entering the scroll elements), which must be avoided as it causes irreversible damage to the compressor.

Danfoss PSH scroll compressors can tolerate occasional flooded starts as long as the total system charge does not exceed the maximum compressor refrigerant charge.

The surface sump heaters are designed to protect the compressor against off-cycle migration of refrigerant.

A suitable test to evaluate the risk of off-cycle migration is the following:

• Stabilize the non running system at 5°C ambient temperature,

• Raise the ambient temperature to 20°C and keep it for 10 minutes,

• Start the compressor and monitor sump temperature, sight glass indication and sound level.

The presence of liquid in the crankcase can be easily detected by checking the sump level through the oil sight glass. Foam in the oil sump indicates a flooded start.

A noisy start, oil loss from the sump and sump cool down are indications for migration.

Depending on the amount of migration graduate measures shall be taken:

• Sump heater (pre installed)

• Liquid line solenoid valve

• Pump down cycle compressor to evacuate refrigerant in the compressor. Start the compressor for 1 second, then wait for 1 to 2 minutes. This operation must be repeated for each compressor individually: on on on

At initial start-up or after power shortage, it is recommended to energize surface sump heater to remove refrigerant 6 hours in advance. A quicker start-up is possible by ”jogging“ the

After 3 or 4 jogs the compressor can be started.

Then, optimum management of the Surface

Sump Heater (SSH) is provided by the operating

Control System (OCS).

34 FRCC.PC.021.A5.02

Application Guidelines

Liquid line solenoid valve

(LLSV)

Pump-down cycle

Liquid flood back

System design recommendations

A LLSV may be used to isolate the liquid charge on the condenser side, thereby preventing against charge transfer or excessive migration to the compressor during off-cycles. The quantity of refrigerant on the low-pressure side of the system can be further reduced by using a pumpdown cycle in association with the LLSV.

A pump-down cycle represents one of the most effective ways to protect against the off-cycle migration of liquid refrigerant. Once the system has reached its set point and is about to shut off, the LLSV on the condenser outlet closes.

The compressor then pumps the majority of the refrigerant charge into the condenser and receiver before the system stops on the low pressure pump-down switch. This step reduces the amount of charge on the low side in order to prevent off-cycle migration. The recommended low-pressure pump-down switch setting is 1.5 bar below the nominal evaporating pressure.

It shall not be set lower than 1.7 bar(g). For suggested wiring diagrams, please see section

”Suggested wiring diagrams“.

• While the thermostat is off, the number of pressure switch resets should be limited to avoid short cycling of the compressor. Use dedicated wiring and an additional relay which allows for one shot pump-down.

The pump-down allows to store all the refrigerant in the high pressure side circuit. On unitary or close-coupled systems, where the system refrigerant charge is expected to be both correct and definable the entire system charge may be stored in the condenser during pumpdown if all components have been properly sized.

Other application needs a liquid receiver to store the refrigerant.

Tests for pump down cycle approval :

• As the pump-down switch setting is inside the application envelope, tests should be carried out to check unexpected cut-out during transient conditions (ie. defrost – cold starting).

When unwanted cut-outs occur, the low pressure pump-down switch can be delayed. In this case a low pressure safety switch without any delay timer is mandatory.

Receiver dimensioning requires special attention.

The receiver shall be large enough to contain part of the system refrigerant charge but it shall not be dimensioned too large. A large receiver easily leads to refrigerant overcharging during maintenance operation.

During normal operation, refrigerant enters the compressor as a superheated vapour. Liquid flood back occurs when a part of the refrigerant entering the compressor is still in liquid state.

Danfoss PSH scroll compressors can tolerate occasional liquid flood back. However system design must be such that repeated and excessive flood back is not possible.

A continuous liquid flood back will cause oil dilution and, in extreme situations lead to lack of lubrication and high rate of oil leaving the compressor.

Liquid flood back test - Repetitive liquid flood back testing must be carried out under expansion valve threshold operating conditions: a high pressure ratio and minimum evaporator load, along with the measurement of suction superheat, oil sump temperature and discharge gas temperature.

the saturated suction temperature, or should the discharge gas temperature be less than 35K above the saturated discharge temperature, this indicates liquid flood back.

Continuous liquid flood back can occur with a wrong dimensioning, a wrong setting or malfunction of the expansion device or in case of evaporator fan failure or blocked air filters.

During operations , liquid flood back may be detected by measuring either the oil sump temperature or the discharge gas temperature.

If at any time during operations, the oil sump temperature drops to within 10K or less above

A suction accumulator providing additional protection as explained hereunder can be used to solve light continuous liquid flood back.

FRCC.PC.021.A5.02

35

Application Guidelines

Oil equalisation

Test conditions

System design recommendations

Suction accumulator: a suction accumulator offers protection against refrigerant flood back at start-up, during operations or defrosting by trapping the liquid refrigerant upstream from the compressor. The suction accumulator also protects against off-cycle migration by providing additional internal free volume to the low side of the system.

The accumulator should not be sized for less than 50 % of the total system charge. Tests must be conducted to determine the actual refrigerant holding capacity needed for the application

.

Depending on the operating conditions it may happen that the recommended connections of the accumulator are one size smaller than the suction line.

A suction accumulator must be carefully dimensioned, taking into account the refrigerant charge as well as the gas velocity in the suction line.

Suction gas in a hermetic compressor flows via the oil sump which makes it more difficult to maintain equal pressure in the sumps of parallel compressors. Since oil equalisation usually depends on equal sump pressures this is a point of special attention. Danfoss Commercial

Compressors has developed specially adapted

Tests shall be done at three points in final application envelope:

 ARI-based conditions

 Low evaporation (SH10K): low flow rate / pure oil/ low oil level

 High load (SH10K): high flow rate/ diluted oil/ high oil level oil equalisation systems which ensure proper oil balancing between the manifold compressors but it is always recommended to carry out some tests to validate effective operation and oil equalisation of compressors in parallel installation at any operating conditions of final application.

Low evaporation

ARI condition

High load

Test sequences

Oil level criteria

 Continuous for all compressors: 100% charge

(all compressors continuous running)

 Continuous with partial charge: all partial charges configuration must be tested

 On/Off test: after 2 minutes shutdown of any compressor, the oil level has to retrieve a proper oil level within 1 minute when the compressor is switched back on.

 Transient 100% load: in transient condition such as end of defrost with temporary liquid flood back, check that oil return to normal level.

 The oil level of running compressors must be visible or full in the sight glass of running compressors at all operating conditions described before.

 The oil level must retrieve a visible level in all compressors after the unit is stopped.

 The oil level of idle compressors may disappear in the oil sight glass.

 Oil level top up might be necessary to retrieve a visible oil level in the sight glasses. Always use a Danfoss oil from new can (see section accessories).

compressor oil level might decrease. In order to avoid any loss of oil, regular unit stops might be needed to re equilibrate oil levels in the compressors.

36 FRCC.PC.021.A5.02

Application Guidelines

Low ambient application

Low ambient start-up

Specific application recommendations

Low ambient operations

Under cold ambient conditions (<0°C), upon start-up the pressure in the condenser may be so low that a sufficient pressure differential across the expansion device cannot be developed to properly feed the evaporator.

Early feeding of the evaporator and management of the discharge pressure could help to attenuate these effects.

As a result, the compressor may go into a deep vacuum, which can lead to compressor failure due to internal arcing and instability in the scroll wraps. Under no circumstances should the compressor be allowed to operate under vacuum. The low-pressure control must be set in accordance with the table section ”Low pressure“ in order to prevent this from happening.

Low pressure differentials can also cause the expansion device to ”hunt“ erratically, which might cause surging conditions within the evaporator, with liquid spillover into the compressor. This effect is most pronounced during low load conditions, which frequently occur during low ambient conditions.

The Danfoss PSH scroll compressor requires a minimum pressure differential of 6 to 7 bar between the suction and discharge pressures to force the orbiting scroll down against the oil film on the thrust bearing. Anything less than this differential and the orbiting scroll can lift up, causing a metal-to-metal contact. It is therefore necessary to maintain sufficient discharge pressure in order to ensure this pressure differential. Care should be taken during low ambient operations when heat removal from air-cooled condensers is greatest and head pressure control may be required for low ambient temperature applications. Operation under low pressure differential may be observed by a significant increase in the sound power level generated by the compressor.

It is recommended that the unit be tested and monitored at minimum load and low ambient conditions as well. The following considerations should be taken into account to ensure proper system operating characteristics.

levels during low loading periods. A minimum of

5 K stable superheat is required.

Head pressure control under low ambient conditions: Several possible solutions are available to prevent the risk of compressor to vacuum and low pressure differential between the suction and discharge pressures.

In air-cooled machines, cycling the fans with a head pressure controller will ensure that the fans remain off until the condensing pressure has reached a satisfactory level. Variable speed fans can also be used to control the condensing pressure. In water-cooled units, the same can be performed using a water regulator valve that is also operated by head pressure, thereby ensuring that the water valve does not open until the condensing pressure reaches a satisfactory level.

The minimum condensing pressure must be set at the minimum saturated condensing temperature shown in the application envelopes.

Expansion device : The expansion device should be sized to ensure proper control of the refrigerant flow into the evaporator. An oversized valve may result in erratic control.

This consideration is especially important in manifolded units where low load conditions may require the frequent cycling of compressors.

This can lead to liquid refrigerant entering the compressor if the expansion valve does not provide stable refrigerant super-heat control under varying loads.

Under very low ambient conditions, in which testing has revealed that the above procedures might not ensure satisfactory condensing and suction pressures, the use of a head pressure control valve is recommended. Note: This solution requires extra refrigerant charge, which can introduce other problems. A non-return valve in the discharge line is recommended and special care should be taken when designing the discharge line.

The superheat setting of the expansion device should be sufficient to ensure proper superheat

For further information, please contact Danfoss.

FRCC.PC.021.A5.02

37

Application Guidelines

Low load operation

Brazed plate heat exchangers

Electronic expansion valve

Reversible heat pump systems

Discharge line and reversing valve

Specific application recommendations

The compressors should be run for a minimum period in order to ensure that the oil has sufficient time to properly return to the compressor sump and that the motor has sufficient time to cool under conditions of lowest refrigerant mass flows.

A brazed plate heat exchanger needs very little internal volume to satisfy the set of heat transfer requirements. Consequently, the heat exchanger offers very little internal volume for the compressor to draw vapour from on the suction side. The compressor can then quickly enter into a vacuum condition. It is therefore important that the expansion device be sized correctly and that a sufficient pressure differential across the expansion device be available to ensure adequate refrigerant feed into the evaporator.

This aspect is of special concern when operating the unit under low ambient and load conditions.

For further information on these conditions, please refer to the previous sections.

Due to the small volume of the brazed plate heat exchanger, no pump-down cycle is normally required. The suction line running from the heat exchanger to the compressor must be trapped to avoid refrigerant migration to the compressor.

When using a brazed plate condenser heat exchanger, a sufficient free volume for the discharge gas to accumulate is required in order to avoid excess pressure build-up. At least 1 meter of discharge line is necessary to generate this volume. To help reduce the gas volume immediately after start-up even further, the supply of cooling water to the heat exchanger may be opened before the compressor starts up so as to remove superheat and condense the incoming discharge gas more quickly.

The use of an electronic expansion valve requires a specific compressor start / stop control.

compressor. Ensure that the EXV closes when the supply voltage to the controller is interrupted (ie power cut off) by the use of a battery back up.

A specific compressor start sequence control has to be set when an electronic expansion valve

(EXV) is used. The sequence must be adjusted according to the EXV step motor speed to allow time for the EXV to open before the compressor starts to avoid running under vacuum conditions.

The EXV should be closed at compressor stop not to let refrigerant in liquid phase entering the

EXV Opened

Closed

Compressor On

Off

Transients are likely to occur in reversible heat pump systems, i.e. a changeover cycle from cooling to heating, defrost or low-load short cycles. These transient modes of operation may lead to liquid refrigerant carry-over (or flood back) or excessively wet refrigerant return conditions. As such, reversible cycle applications require specific precautions for ensuring a long compressor life and satisfactory operating characteristics. Regardless of the refrigerant charge in the system, specific tests for repetitive flood back are required to confirm whether or not a suction accumulator needs to be installed.

The following considerations cover the most important issues when dealing with common applications. Each application design however should be thoroughly tested to ensure acceptable operating characteristics.

The Danfoss PSH scroll compressor is a high volumetric machine and, as such, can rapidly build up pressure in the discharge line if gas in the line becomes obstructed even for a very short period of time which situation may occur with slow-acting, reversing valves in heat pumps.

Discharge pressures exceeding the operating envelope may result in nuisance high-pressure switch cutouts and place excess strain on both the bearings and motor.

To prevent such occurrences, it is important that a 1-meter minimum discharge line length be allowed between the compressor discharge port and the reversing valve or any other restriction. This gives sufficient free volume for the discharge gas to collect and to reduce the pressure peak during the time it takes for the valve to change position. At the same time, it is important that the selection and sizing of the reversing or 4-way valve ensure that the valve

38 FRCC.PC.021.A5.02

Application Guidelines Specific application recommendations

Check with the valve manufacturer for optimal sizing and recommended mounting positions.

Defrost and reverse cycle

The Danfoss PSH scroll compressor has the ability to withstand a certain amount of liquid refrigerant dynamic slug.

When compressors are installed in parallel, in order to limit liquid amount handled per compressor when beginning and ending defrost, it is recommended to avoid running part load

(keep all compressors running or keep them stopped when moving 4-way valves).

In order to limit liquid amount handled per compressor when beginning & ending defrost, one of the 2 defrost cycle logics are required:

 stop all compressors before moving the

4 way valve:

˜ first stop compressors

˜ wait for 10 seconds

˜ move the 4 way valve

˜ wait for 2 seconds

˜ restart the compressors with a max. 0.5 second delay between 2 successive starts or

 keep all compressors running during defrost cycle

Defrost cycle logic must respect all system components recommendations, in particular 4 way valve Max. Operating Pressure Differential.

Start of defrost sequence

End of defrost sequence

Compressor 1 on

Compressor 1 off

Compressor 2 on

Compressor 2 off

Compressor 3 on

Compressor 3 off

4 way valve position 1

4 way valve position 2

10" 2" 10" 2"

Start of defrost sequence

End of defrost sequence

Compressors on

Compressors off

4 way valve 1

4 way valve 2

EXV can also be opened when compressors are stopped and before 4 way valve is moving in order to decrease pressure difference. Opening degree and time have to be set in order to keep a minimum pressure difference for 4 way valve moving. Each application design however should be thoroughly tested to ensure acceptable operating characteristics.

Suction line accumulator

switches quickly enough to prevent against too high discharge pressure and nuisance highpressure cutouts.

The use of a suction line accumulator is strongly recommended in reversible-cycle applications.

This because of the possibility of a substantial quantity of liquid refrigerant remaining in the evaporator, which acts as a condenser during the heating cycle.

This liquid refrigerant can then return to the compressor, either flooding the sump with refrigerant or as a dynamic liquid slug when the cycle switches back to a defrost cycle or to normal cooling operations.

Sustained and repeated liquid slugging and flood back can seriously impair the oil’s ability to lubricate the compressor bearings. This situation can be observed in wet climates where it is necessary to frequently defrost the outdoor coil in an air source heat pump. In such cases a suction accumulator becomes mandatory.

Water utilizing systems

Apart from residual moisture in the system after commissioning, water could also enter the refrigeration circuit during operation. Water in the system shall always be avoided. Not only because it can shortly lead to electrical failure, sludge in sump and corrosion but in particular because it can cause serious safety risks.

Common causes for water leaks are corrosion and freezing.

Corrosion: Materials in the system shall be compliant with water and protected against corrosion.

Freezing: When water freezes into ice its volume expands which can damage heat exchanger walls and cause leaks. During off periods water inside heat exchangers could start freezing when ambient temperature is lower than 0°C. During on periods ice banking could occur when the circuit is running continuously at too low load.

Both situations should be avoided by connecting a pressure and thermostat switch in the safety line.

FRCC.PC.021.A5.02

39

Application Guidelines

Starting sound level

Running sound level

Stopping sound level

Sound and vibration management

During start-up transients it is natural for the compressor sound level to be slightly higher than during normal running. PSH scroll compressors exhibit very little increased start-up transient sound. If a compressor is miswired, the compressor will run in reverse. Reverse compressor rotation is characterized by an objectionable sound. To correct reverse rotation, disconnect power and switch any two of the three power leads at the unit contactor.

Never switch leads at the compressor terminals.

Bottom insulation delivered together with the compressor incorporates sound proofing materials and offer excellent high and low frequency attenuation.

As an option, compressor acoustic hoods have been developed to meet specific extra-low noise requirements.

Sound power dB(A)

PSH051

PSH064

PSH077

PSH104

PSH115

PSH130

PSH128

PSH141

PSH154

PSH153

PSH152

PSH231

88.8

87

88.8

91.8

88.8

Sound power dB(A)

50Hz 60Hz

84 87.5

87

84

87

90

88.5

90.5

88.8

90

87

91.9

93

91

92.3

91.5

92.3

94.8

93.3

PSH compressors are equipped with a discharge valve which closes at compressor shut down and thus prevents the compressor from running backwards.

This reduces the stopping sound to a metallic click caused by the closing valve.

When the pressure difference or gas flow at shut down should be very low, this can delay the discharge valve from closing and lead to a longer noise duration.

40 FRCC.PC.021.A5.02

Application Guidelines Installation

Compressor handling and storage

Each Danfoss PSH scroll compressor is equipped with two lift rings on the top shell. Always use both these rings when lifting the compressor.

Use lifting equipment rated and certified for the weight of the compressor. A spreader bar rated for the weight of the compressor is highly recommended to ensure a better load distribution. The use of lifting hooks closed with a clasp and certified to lift the weight of the compressor is also highly recommended.

Always respect the appropriate rules concerning lifting objects of the type and weight of these compressors. Maintain the compressor in an upright position during all handling manoeuvres

(maximum of 15° from vertical).

Never use only one lifting lug to lift the compressor. The compressor is too heavy for the single lug to handle, and the risk is run that the lug could separate from the compressor with extensive damage and possible personal injury as a result.

R410A and between -35°C and 70°C when charged whith nitrogen from factory.

When the compressor is mounted as part of an installation, never use the lift rings on the compressor to lift the installation. The risk is run that the lugs could separate from the compressor or that the compressor could separate from the base frame with extensive damage and possible personal injury as a result.

Never apply force to the terminal box with the intention of moving the compressor, as the force placed upon the terminal box can cause extensive damage to both the box and the components contained inside.

HEAVY

Store the compressor not exposed to rain, corrosive or flammable atmosphere and between -35°C and 51°C when charged with do not lift manually

Compressor mounting

Maximum inclination from the vertical plane while operating must not exceed 3 degrees.

Compressors are delivered with pre mounted rigid spacers dedicated to parallel mounting.

The grommets must be compressed until contact between the flat washer and the steel mounting sleeve is established. The grommets attenuate to a great extent the transmission of compressor vibrations to the base frame.

If used in single applications, the compressor must be mounted with the flexible grommets as available in accessory conversion kit 8156138.

1 manifoldable compressor with rigid spacers

The required bolt size for the PSH051-064-

077 compressors is HM8-55. This bolt must be tightened to a torque of 21 Nm.

1 single compressor with rubber grommets

29.5 mm

Rigid spacers to remove

HM 8 bolt

Lock washer

Nut

Flat washer

Rigid spacer

Nut

Rubber grommets from kit 8156138

HM 8 bolt

Lock washer

Flat washer

Steel mounting sleeve

Rubber grommet

Nut

Compressor base plate

28 mm

FRCC.PC.021.A5.02

41

Application Guidelines

Parallel mounting

Installation

Compressors PSH051-064-077 come delivered with rigid mounting spacers already installed on the compressor. They must be used in this configuration for parallel mounting.

Recommended rails configuration : Danfoss

Commercial Compressors does not supply the rails described here.

Tandem rails configuration

*

5

2 x 26

R12

80

Ø 10 x 4

*

Ø 25 x 3

30

Material: steel

4 x M8 nuts

*

30

94 279.4

453.7

220.6

279.4

453.7

968.4

*: Unit Frame must include a sufficiently strong structure at these positions to support tandem rails.

Trio rails configuration

*

30 453.7

4 x Ø 25 Ø 10

*

500

*

453.7

6 x M8 nuts

*

94 279.4

220.6

279.4

1467.9

220.6

279.4

42 FRCC.PC.021.A5.02

Application Guidelines

Parallel mounting feet

Installation

For parallel mounting, rubber grommets and spacer must be installed below the rails.

Tightening torque 55N.M

HM10x100 tightening torque 44N.M

These parts are included in the tandem of trio accessory kit code number 7777xxx described below.

Grommet sleeve

Flat washer

Rubber washers

Tandem grommet

 &  Rigid spacers

 Tandem rail

Tightening torque 16N.M

Included in kit 7777xxx

Supplied with the compressor

Not supplied

Tandem kit code numbers

When different compressor models are installed in parallel, in order to balance compressor sump pressures, it is necessary to use a suction washer in one of the compressor. This suction washer is supplied within kits described below. It must always be installed on compressor 1.

Tandem model Compressor 1 Compressor 2

PSH104

PSH115

PSH130

PSH128

PSH141

PSH154

PSH051

PSH051

PSH064

PSH051

PSH064

PSH077

PSH051

PSH064

PSH064

PSH077

PSH077

PSH077

Code nb for ordering

7777041

7777037

7777041

7777048

7777037

7777041

Suction washer (restrictor) kit

Reference

Not needed

5311570P01

Not needed

5311579P05

5311579P01

Not needed

Diameter (mm)

31

29

31

Outline drawing

8556121

8556148

8556122

8556148

8556148

8556123

Tandem piping design recommendations, applicable to all tandem configurations.

Compressor 2

Compressor 1

Discharge right 1”3/8

Suction right 2”1/8

1”5/8

Oil equalisation

1”3/8

1”1/8 (2x)

Discharge left 1”3/8

Suction left

FRCC.PC.021.A5.02

43

Application Guidelines

Trio kit code numbers

Left suction

Installation

CP 1 CP 2 CP 3 CP 2

Right suction

CP 3 CP 1

Trio model

PSH153

PSH192

PSH231

Cp 1 Cp 2 Cp 3 Suction side

PSH051 PSH051 PSH051

PSH064 PSH064 PSH064

PSH077 PSH077 PSH077

Left

Right

Left

Right

Left

Right

Suction washer (restrictor) kit

Code nb for ordering Reference Diameter (mm) Washer in suction of

7777040

7777039

5311579P02

5311579P03

33

34.5

Cp3

Cp1 & cp3

7777040

7777039

7777040

5311579P02

5311579P03

5311579P02

Not needed

33

34.5

33

Cp3

Cp1 & cp3

Cp3

Outline drawing

8556146

8556147

8556147

Tandem and trio piping design

Tandem and trio

Handling

Compressor holding charge

For each tandem and trio configuration specific outline drawings are available as indicated on the previous pages. These drawings must always be respected.

No changes shall be made to the indicated tubing diameter and fitting types.

Minimum straight length indicated on drawings must be respected.

The oil equalisation line shall be made of copper tube and assembled in such a way that it does not extend above the connection height and must be horizontal so as not to trap oil.

Oil equalisation fitting must not be heated during installation and servicing. This could damage to the compressor and impact oil equalisation balancing.

Danfoss Commercial Compressors recommends using the lift and handling devices, as shown in picture beside, and that the following procedure be used to prevent damage.

 Two lift rings are provided on each compressor.

Use all four rings.

 Maximum loads authorized per sling and for the hoist hook must not be lower than the weight of the assembly.

 The minimum spreader bar length must be at least equal to the centre distance between the two compressors to prevent bending the frame.

 When lifting, use a spreader block between the compressors to prevent any unit frame damage.

 When the tandem unit is already mounted into an installation, never lift the complete installation by using the lift rings on the compressors.

Spreader block

Slings

Spreader bar

Frame

Each compressor is shipped with a nominal dry nitrogen holding charge between 0.3 and 0.7 bar and is sealed with elastomer plugs.

Before the suction and discharge plugs are removed, the nitrogen holding charge must be released via the suction schrader valve to avoid an oil mist blowout. Remove the suction plug first and the discharge plug afterwards.

The plugs shall be removed only just before connecting the compressor to the installation in order to avoid moisture from entering the compressor. When the plugs are removed, it is essential to keep the compressor in a upright position so as to avoid oil spillage.

44 FRCC.PC.021.A5.02

Application Guidelines

System cleanliness

Tubing

Brazing and soldering

Copper to copper

Connections

Dissimilar metals

Connection

Installation

The refrigerant compression system, regardless of the type of compressor used, will only provide high efficiency and good reliability, along with a long operating life, if the system contains solely the refrigerant and oil it was designed for. Any other substances within the system will not improve performance and, in most cases, will be highly detrimental to system operations.

System contamination is one of main factors affecting equipment reliability and compressor service life. It is important therefore to take system cleanliness into account when assembling a refrigeration system.

The presence of non-condensable substances and system contaminants such as metal shavings, solder and flux, have a negative impact on compressor service life. Many of these contaminants are small enough to pass through a mesh screen and can cause considerable damage within a bearing assembly.

During the manufacturing process, circuit contamination may be caused by:

• Brazing and welding oxides,

• Filings and particles from the removal of burrs in pipe-work,

• Brazing flux,

• Moisture and air.

Consequently, when building equipment and assemblies, the precautions listed in the following paragraphs must be taken.

The use of highly hygroscopic polyolester oil in R410A compressors requires that the oil be exposed to the atmosphere as short as possible.

Only use clean and dehydrated refrigeration grade copper tubing. Tube-cutting must be carried out so as not to deform the tubing roundness and to ensure that no foreign debris remains within the tubing. Only refrigerant grade fittings should be used and these must be of both a design and size to allow for a minimum pressure drop through the completed assembly.

Follow the brazing instructions on next pages.

Never drill holes into parts of the pipe-work where filings and particles can not be removed.

Do not bend the compressor discharge or suction lines or force system piping into the compressor connections, because this will increase stresses that are a potential cause of

When brazing copper-to-copper connections, the use of copper/phosphorus brazing alloy containing 5% silver or more with a melting failure. Recommended brazing procedures and material, are described section ”Compressor connection“.

temperature of below 800°C is recommended.

No flux is required during brazing.

When manipulating dissimilar metals such as copper and brass or steel, the use of silver solder and anti-oxidant flux is necessary.

FRCC.PC.021.A5.02

45

Application Guidelines

Compressor connection

Installation

When brazing the compressor fittings, do not overheat the compressor shell, which could severely damage certain internal components due to excessive heating. Use of a heat shield and/or a heat-absorbent compound is highly recommended. Due to the relatively sizable tubing and fitting diameters a double-tipped torch using acetylene is recommended for brazing operation on PSH compressors.

For brazing the suction and discharge connections, the following procedure is advised:

• Make sure that no electrical wiring is connected to the compressor.

• Protect the terminal box and compressor painted surfaces from torch heat damage

(see diagram).

• Remove the Teflon gaskets when brazing rotolock connectors with solder sleeves.

• Use only clean refrigeration-grade copper tubing and clean all connections.

• Use brazing material with a minimum of 5% silver content.

• Purge nitrogen or CO2 through the compressor in order to prevent against oxidation and flammable conditions. The compressor should not be exposed to the open air for extended periods.

• Use of a double-tipped torch is recommended.

• Apply heat evenly to area A until the brazing temperature is reached. Move the torch to area B and apply heat evenly until the brazing temperature has been reached there as well, and then begin adding the brazing material. Move the torch evenly around the joint, in applying only enough brazing material to flow the full circumference of the joint.

• Move the torch to area C only long enough to draw the brazing material into the joint, but not into the compressor.

• Remove all remaining flux once the joint has been soldered with a wire brush or a wet cloth. Remaining flux would cause corrosion of the tubing. heat shield

C

B

A

46 FRCC.PC.021.A5.02

Application Guidelines Installation

System pressure test

Leak detection

Vacuum evacuation and moisture removal

Ensure that no flux is allowed to enter into the tubing or compressor. Flux is acidic and can cause substantial damage to the internal parts of the system and compressor.

Before eventual unbrazing the compressor or any system component, the refrigerant charge must be removed from both the high- and low pressure sides. Failure to do so may result in serious personal injury. Pressure gauges must be used to ensure all pressures are at atmospheric level.

The polyolester oil used in PSH compressors is highly hygroscopic and will rapidly absorb moisture from the air. The compressor must therefore not be left open to the atmosphere for a long period of time. The compressor fitting plugs shall be removed just before brazing the compressor. The compressor should always be the last component brazed into the system.

For more detailed information on the appropriate materials required for brazing or soldering, please contact the product manufacturer or distributor. For specific applications not covered herein, please contact

Danfoss for further information.

Always use an inert gas such as nitrogen for pressure testing. Never use other gasses such as oxygen, dry air or acetylene as these may form an inflammable mixture. Do not exceed the following pressures

Pressurize the system on HP side first then LP side to prevent rotation of the scroll. Never let the pressure on LP side exceed the pressure on

HP side with more than 5 bar.

In order to insure LIV integrity, never let the pressure on HP side exceed the pressure on LP side with more than 35 bar.

PSH051 PSH064-077

Maximum compressor test pressure (low side)

Maximum compressor test pressure (high side)

34.3 bar (g) 33.3 bar (g)

48.7 bar (g)

Maximum pressure difference between high & low side of the compressor

35 bar

On PSH51-064-077 models which have an internal non return valve in discharge fitting or if an external non return valve is present on the discharge line, we advise to pressurize the system not quicker than 4.8 bar/s to allow pressure equalization between LP and HP side over scroll elements.

Leak detection must be carried out using a mixture of nitrogen and refrigerant or nitrogen and helium, as indicated in the table below.

Never use other gasses such as oxygen, dry air or acetylene as these may form an inflammable mixture.

Pressurize the system on HP side first then LP side.

Leak detection with refrigerant

Nitrogen & R410A

Leak detection with a mass spectrometer

Nitrogen & Helium

Note 1: Leak detection with refrigerant may be forbidden in some countries. Check local regulations.

Note 2: The use of leak detecting additives is forbidden as they may affect the lubricant properties.

Moisture obstructs the proper functioning of the compressor and the refrigeration system.

Air and moisture reduce service life and increase condensing pressure, and cause excessively high discharge temperatures, which can destroy the lubricating properties of the oil. Air and moisture also increase the risk of acid formation, giving rise to copper platting. All these phenomena can cause mechanical and electrical compressor failure.

PSH compressors are delivered with < 100 ppm moisture level. The required moisture level in the circuit after vacuum dehydration must be

< 100 ppm for systems with a PSH.

• Never use the compressor to evacuate the system.

• Connect a vacuum pump to both the LP &

HP sides.

• Evacuate the system to a pressure of

500 μm Hg (0.67 mbar) absolute.

For these reasons it’s important to perform a vacuum dehydration on the system to remove all residual moisture from the pipe-work after assembly;

Do not use a megohm meter nor apply power to the compressor while it’s under vacuum as this may cause internal damage.

FRCC.PC.021.A5.02

47

Application Guidelines Installation

Filter driers

Refrigerant charging

Refrigerant charge limit

A properly sized & type of drier is required.

Important selection criteria include the driers water content capacity, the system refrigeration capacity and the system refrigerant charge.

The drier must be able to reach and maintain a moisture level of 50 ppm end point dryness

(EPD).

For new installations with PSH compressors with polyolester oil, Danfoss recommends using the Danfoss DML (100% molecular sieve) solid core filter drier. Molecular sieve filter driers with loose beads from third party suppliers shall be avoided. For servicing of existing installations where acid formation is present the Danfoss

For the initial charge the compressor must not run and eventual service valves must be closed.

Charge refrigerant as close as possible to the nominal system charge before starting the compressor.

This initial charging operation must be done in liquid phase. The best location is on the liquid line between the condenser outlet and the filter drier. Then during commissioning, when needed, a complement of charge can be done in liquid phase: slowly throttling liquid in on the low pressure side as far away as possible from the compressor suction connection while compressor is running. The refrigerant charge

Danfoss PSH compressors can tolerate liquid refrigerant up to a certain extend without major problems. However, excessive liquid refrigerant in the compressor is always unfavourable for service life. Besides, the installation cooling capacity may be reduced because of the evaporation taking place in the compressor and/ or the suction line instead of the evaporator.

System design must be such that the amount of liquid refrigerant in the compressor is limited.

In this respect, follow the guidelines given in the section: ”Essential piping design recommendations“ in priority.

Use the tables below to quickly evaluate the required compressor protection in relation with the system charge and the application.

DCL (solid core) filter driers containing activated alumina are recommended.

The drier is to be oversized rather than under sized. When selecting a drier, always take into account its capacity (water content capacity), the system refrigeration capacity and the system refrigerant charge.

After burn out, remove & replace the liquid line filter drier and install a Danfoss type DAS burnout drier of the appropriate capacity. Refer to the DAS drier instructions and technical information for correct use of the burnout drier on the liquid line.

quantity must be suitable for both summer and winter operations.

Vacuum or charge from one side can seal the scrolls and result in a non-starting compressor.

When servicing, always ensure that LP/HP pressures are balanced before starting the compressor.

Be sure to follow all government regulations regarding refrigerant reclamation and storage.

For more detailed information see

”Recommended refrigerant system charging practice“ news bulletin FRCC.EN.050.

Model sor PSH051-064

PSH077

PSH104

PSH115

PSH130

PSH128

PSH141

PSH154

PSH153

PSH192

PSH231

Refrigerant charge limit in the compressor (kg)

13.5

14.5

17.5

23

23

24.5

17.5

17.5

17.5

17.5

17.5

48 FRCC.PC.021.A5.02

Application Guidelines Installation

Cooling only systems,

Packaged units

Cooling only systems with remote condensor and split system units

Reversible heat pump system

REC

Recommended

BELOW charge limit

 No test or additional safeties required

ABOVE charge limit

REQ Refrigerant migration and floodback test

REC Refrigerant migration and floodback test

REQ

Required

REQ

REC

Refrigerant migration and floodback test

Liquid receiver (in association with LLSV and pump down)

REQ

REQ

Specific tests for repetitive floodback

Defrost test

No test or additional safeties required

Insulation resistance and dielectric strength

Insulation resistance on motor pins and thermistor connections must be higher than 1 megohm when measured with a 500 volt direct current megohm tester.

Never perform insulation resistance test on OCS power leads.

PSH scroll compressors are configured with the pump assembly at the top of the shell, and the motor below. As a result, the motor can be partially immersed in refrigerant and oil. The presence of refrigerant around the motor windings will result in lower resistance values to ground and higher leakage current readings. Such readings do not indicate a faulty compressor.

Each compressor motor is tested at the factory with a high potential voltage (hi-pot) that exceeds the UL requirement both in potential and in duration. Leakage current is less than 5 mA.

In testing insulation resistance, Danfoss recommends that the system be first operated briefly to distribute refrigerant throughout the system.

It is not recommended to repeat high voltage test (hi-pot) on motor. If this test must be carried out anyway, it is mandatory to disconnect the

OCS to prevent any damages or destruction.

Following this brief operation, retest the compressor for insulation resistance or current leakage.

Never reset a breaker or replace a fuse without first checking for a ground fault (a short circuit to ground).

FRCC.PC.021.A5.02

49

Application Guidelines

Commissioning

Oil level checking and top-up

Installation

The system must be monitored after initial start-up for a minimum of 60 minutes to ensure proper operating characteristics such as:

• Proper metering device operation and desired superheat readings

• Suction and discharge pressure are within acceptable levels

• Correct oil level in compressor sump indicating proper oil return

• Low foaming in sight glass and compressor sump temperature 10K above saturation temperature to show that there is no refrigerant migration taking place

• Acceptable cycling rate of compressors, including duration of run times

• Current draw of individual compressors within acceptable values (max operating current)

• No abnormal vibrations and noise.

In installations with good oil return and line runs up to 20 m, no additional oil is required.

If installation lines exceed 20 m, additional oil may be needed. 1 or 2% of the total system refrigerant charge (in weight) can be used to roughly define the required oil top-up quantity but in any case the oil charge has to be adjusted based on the oil level in the compressor sight glass.

The oil level can also be checked a few minutes after the compressor stops. When the compressor is off, the level in the sight glass can be influenced by the presence of refrigerant in the oil.

Always use original Danfoss POE oil 160SZ from new cans.

When the compressor is running under stabilized conditions the oil level must be visible in the sight glass.

Top-up the oil while the compressor is idle. Use the schrader connector or any other accessible connector on the compressor suction line and a suitable pump. See News bulletin “Lubricants filling in instructions for Danfoss Commercial

Compressors”.

The presence of foam filling in the sight glass indicates large concentration of refrigerant in the oil and / or presence of liquid returning to the compressor.

50 FRCC.PC.021.A5.02

Application Guidelines

Packaging

Single pack

Ordering information and packaging

Compressor model

PSH051

PSH064

PSH077

Industrial pack

Length (mm)

770

770

770

Width (mm)

600

600

600

Height (mm)

900

900

900

Gross weight (kg)

118

164

172

Compressor model

PSH051

PSH064

PSH077

Nb

6

4

4

Length (mm)

1150

1150

1150

Width (mm)

965

965

965

Height (mm)

768

768

800

Gross weight (kg )

695

658

688

Static stacking pallets

2

2

2

FRCC.PC.021.A5.02

51

Application Guidelines

Ordering information

Ordering information and packaging

Danfoss PSH scroll compressors can be ordered in either industrial pack or single packs. Please use the code numbers from below tables for ordering.

Compressors PSH051-064-077 are delivered with pre-mounted rigid spacers dedicated to parallel mounting. For use in single applications, the rigid spacers must be replaced by flexible grommets which are available as accessory kit 8156138, see section ”Accessories“.

Single pack

Compressor model

PSH051

PSH064

PSH077

Industrial pack

Compressor model

PSH051

PSH064

PSH077

OCS supply voltage

230 V AC

OCS supply voltage

230 V AC

Motor code 4

120H0864

120H0866

120H0868

Code number

Motor code 9

120H0904

120H0906

120H0908

Motor code 4

120H0863

120H0865

120H0867

Code number

Motor code 9

120H0903

120H0905

120H0907

52 FRCC.PC.021.A5.02

Application Guidelines Accessories

Valves, adapters, connectors & gaskets for use on suction and discharge connections

Solder sleeve adapter sets

Type Code n°

7765028

Description

Solder sleeve adapter set (2"1/4 rotolock, 1"5/8 ODF)

(1"3/4 rotolock, 1"1/8 ODF)

Application

PSH051-064-077

Rotolock adapters

Type Code n° Description

120Z0364 Rotolock adapter (1"3/4 Rotolock, 1"1/8 ODF)

120Z0432 Rotolock adapter (2-1/4" Rotolock, 1"5/8 ODF)

Application

Models with 1"1/8 ODF

Models with 1"5/8 ODF

Gaskets and gasket sets

Type

G07

G07

G08

G08

Code n°

8156132 Gasket, 1"3/4

7956003 Gasket, 1"3/4

8156133 Gasket, 2"1/4

7956004 Gasket, 2"1/4

Description

Solder sleeves

Type

P02

P03

Code n° Description

8153004 Solder sleeve, P02 (1"3/4 Rotolock, 1"1/8 ODF)

8153006 Solder sleeve, P03 (2"1/4 Rotolock, 1"5/8 ODF)

Rotolock nuts

Type Code n°

8153124 Rotolock nut, 1"3/4

8153126 Rotolock nut, 2"1/4

Description

Rotolock service valves and valve sets (without gasket)

Type

V02

V02

V03

V03-V02

Code n° Description

8168028 Rotolock valve, V02 (1"3/4 Rotolock, 1"1/8 ODF)

7968009 Rotolock valve, V02 (1"3/4 Rotolock, 1"1/8 ODF)

8168026 Rotolock valve, V03 (2-1/4" Rotolock, 1"5/8 ODF)

7703383 Valve set, V03 (2-1/4"~1"5/8), V02 (1"3/4~1"1/8)

Packaging

Multipack

Pack size

6

Packaging

Multipack

Multipack

Pack size

10

10

Application

Models with 1"3/4 rotolock connection

Models with 2"1/4 rotolock connection

Packaging

Multipack

Pack size

10

Industry pack 50

Multipack 10

Industry pack 50

Application

Models with 1"3/4 rotolock connection

Models with 2"1/4 rotolock connection

Packaging

Multipack

Multipack

Pack size

10

10

Application

Models with 1"3/4 rotolock connection

Models with 2"1/4 rotolock connection

Packaging

Multipack

Multipack

Pack size

10

10

Application

Models with 1"3/4 rotolock connection

Models with 2"1/4 rotolock connection

PSH051-064-077

Packaging

Multipack

Pack size

6

Industry pack 24

Multipack 6

Multipack 4

FRCC.PC.021.A5.02

53

Application Guidelines Accessories

Surface sump heaters

Type Code n° Description

120Z0360 Surface sump heater + Bottom insulation, 56 W, 24 V, CE, UL

120Z0376 Surface sump heater + Bottom insulation, 56 W, 230 V, CE , UL

3 phase soft start equipment

Type Code n° Description

MCI50CM 037N0401 Electronic soft start kit, MCI 50 CM

Application

PSH051-064-077

Application

PSH051-064-077

Packaging

Multipack

Multipack

Pack size

6

6

Packaging

Single pack

Pack size

1

Tandem kits

Type Code n° Description

7777041 Suction washer, rigid spacer, sleeve for oil connect

7777037 Suction washer, rigid spacer, sleeve for oil connect

7777048 Suction washer, rigid spacer, sleeve for oil connect

Application

PSH even tandem

PSH051+064, PSH064+077

PSH051+077

Trio kits

Type Code n° Description

7777039 Suction washer, rigid spacer, sleeve for oil connect

7777040 Suction washer, rigid spacer, sleeve for oil connect

Acoustic hoods and spare parts

Acoustic hoods

Type Code n° Description

120Z0579 Acoustic hood for scroll compressor

Bottom insulation

Type Code n° Description

120Z0353 Bottom insulation for scroll compressor

Mounting kits

Type Code n°

8156138

120Z0495

Description

Mounting kit for 1 scroll compressor including 4 grommets, 4 sleeves, 4 bolts, 4 washers

Mounting kit for 1 scroll compressor including 4 rigid spacers

Application

PSH trios (right suction)

PSH trios (left suction)

Application

PSH051-064-077

Application

PSH051-064-077

Application

PSH051-064-077

PSH051-064-077

Packaging

Single pack

Single pack

Single pack

Pack size

1

1

1

Packaging

Single pack

Single pack

Pack size

1

1

Packaging

Single pack

Pack size

1

Packaging

Single pack

Pack size

1

Packaging

Single pack

Single pack

Pack size

1

1

54 FRCC.PC.021.A5.02

Application Guidelines Accessories

Terminal boxes, covers &

T-block connectors

Type Code n° Description

8173021 T block connector 60 x 75 mm

120Z0483 Terminal box with 230V OCS

120Z0563 Terminal box with 230V OCS

120Z0565 Terminal box with 230V OCS

120Z0485 Terminal box cover

120Z0486 OCS connectors For OCS version

Lubricants / oils

Type

160SZ

160SZ

Code n° Description

7754023 POE lubricant, 160SZ, 1 litre can

120Z0571 POE lubricant, 160SZ, 2.5 litre can

Miscellaneous

Type Code n° Description

8156129 Gasket for oil sight glass (white teflon)

7956005 Gasket for oil sight glass (white teflon)

8154001 Danfoss CC blue spray paint

Sensors & cables

Type Code n° Description

060G5707 HP sensor

060G0090

060G0008 LP sensor

120Z0482 DGT sensor with cable

061L4223 Liquid Injection Valve coil with cable

120Z0487 Liquid Injection Valve

120Z0478 Can Bus cable with cable glands

120Z0479 Can Bus cable with cable glands

Communication tools

Type

080G0073

080G0294

080G0075

Code n°

MMIMYK

MMIGRS

RJ11 cable

Description

Application

PSH051-064-077

PSH051

PSH064

PSH077

PSH051-064-077

PSH051-064-077

Packaging

Multipack

Single pack

Single pack

Single pack

Single pack

Single pack

1

1

1

1

Pack size

10

1

Application

PSH051-064-077

Packaging

Multipack

Multipack

Pack size

12

4

Application

PSH051-064-077

PSH051-064-077

PSH051-064-077

Packaging

Pack size

Multipack 10

Industry pack 50

Single pack 1

Application

PSH051-064-077

PSH tandem assembly

PSH trio assembly

Packaging

Single pack

Single pack

Single pack

Single pack

Single pack

Single pack

Single pack

Pack size

1

1

1

1

1

1

1

Application

PSH051-064-077

Packaging

Single pack

Single pack

Single pack

Pack size

1

1

1

FRCC.PC.021.A5.02

55

Application Guidelines Updates

Previous Version Current Version

· Page 17: Pressure equipment directive 2014/68/

EU

· Page 25: Pressure settings

· Page 47: Maximum compressor test pressure

(high side) : 48 bar (g)

· Page 17: Updated Pressure equipment directive

2014/68/EU

· Page 25: Updated pressure settings

· Page 47: Maximum compressor test pressure

(high side) : 48.7

bar (g)

56 FRCC.PC.021.A5.02

Danfoss Commercial Compressors

is a worldwide manufacturer of compressors and condensing units for refrigeration and HVAC applications. With a wide range of high quality and innovative products we help your company to find the best possible energy efficient solution that respects the environment and reduces total life cycle costs.

We have 40 years of experience within the development of hermetic compressors which has brought us amongst the global leaders in our business, and positioned us as distinct variable speed technology specialists. Today we operate from engineering and manufacturing facilities spread across three continents.

Danfoss Turbocor Compressors

Danfoss Inverter Scrolls

Danfoss Scrolls

Danfoss Optyma Condensing Units

Danfoss Maneurop Reciprocating Compressors

Danfoss Light Commercial Refrigeration

Compressors

Our products can be found in a variety of applications such as rooftops, chillers, residential air conditioners, heatpumps, coldrooms, supermarkets, milk tank cooling and industrial cooling processes.

http://cc.danfoss.com

Danfoss Commercial Compressors, BP 331, 01603 Trévoux Cedex, France | +334 74 00 28 29

FRCC.PC.021.A5.02

© Danfoss | DCS(CC) | 2017.09

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Key Features

  • High efficiency
  • Reliability
  • Low noise levels
  • Range of capacities from 5.0 to 7.7 kW
  • Suitable for use in both cooling and heating applications

Related manuals

Frequently Answers and Questions

What refrigerant do these compressors use?
R410A
What is the capacity range of these compressors?
5.0 to 7.7 kW
Are these compressors suitable for use in both cooling and heating applications?
Yes

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