5.2. Functions of the P19 transducer

TEMPERATURE and HUMIDITY

TRANSDUCER

P19 TYPE

USER’S MANUAL

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2

Contents

1. APPLICATION .................................................................. 5

2. TRANSDUCER SET .......................................................... 5

3. BASIC REQUIREMENTS, OPERATIONAL SAFETY ....... 6

4. INSTALLATION .................................................................. 6

4.1. Overall dimensions and working position ................... 6

4.2. Electrical connections ................................................. 7

4.3. Assembly .................................................................... 8

5. SERVICING ...................................................................... 10

5.1. Messages after supply is switched on ...................... 10

5.2. Functions of the P19 transducer .............................. 10

5.2.1. Calculated values .................................................. 11

5.2.2. Default parameters ................................................ 12

6. MODBUS PROTOCOL ON RS-485 SERIAL PORT ....... 12

6.1. Serial interface connection ....................................... 12

6.2. Description of the MODBUS protocol ...................... 13

6.3 Description of implemented MODBUS functions ....... 13

6.4 Register map ............................................................. 18

6.5 Read/Write registers .................................................. 19

6.6 Read only registers ............................................... 21

7. EMERGENCY RESTORATION OF RS-485 PARAMETERS......22

8. TECHNICAL DATA .......................................................... 23

9. ORDERING CODE ........................................................... 25

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4

1. APPLICATION

The P19 transducer is device destined for the continuous

measurement and conversion of relative humidity and ambient temperature into a digital form (protocol MODBUS RS-485). The transducer is fixed on a wall. The programming of the transducer is possible by means of the RS-485 interface.

Fig. 1. View of the P19 transducer.

2. TRANSDUCER SET

The delivered controller set is composed of:

1. transducer P19 ................................... 1 pc

2. user’s manual ..................................... 1 pc

3. guarantee card.................................... 1 pc

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3. BASIC REQUIREMENTS, OPERATIONAL SAFETY

In the security scope, the transducer meets the requirements of the EN 61010 -1 standard.

Remarks concerning the operator safety: l

All operations concerning transport, installation, and commissioning

as well as maintenance must be carried out by qualified, skilled

personnel.

l

Before switching the transducer on, one must check the correctness

of connections to the network.

l

The device is destined to be installed and used in industrial

electromagnetic environment conditions.

When unpacking the P19 transducer, please check whether the type and version code on the data plate correspond to the order code.

4. INSTALLATION

4.1. Overall dimensions and working position

The P19 transducer is designed to be mounted on a wall by means of a screw connection. Transducer housing is assembled of two parts: front part and back part. The transducer has screw connectors placed inside the transducer, which enable the connection of external wires of 1 mm 2 cross-section.

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Fig. 2. Overall dimensions of the P19 transducer and correct working position

Fig. 3. Lay-out of assembly holes in back part of housing

4.2. Electrical connections

The P19 transducer has 4 connecting terminals to which there is access after removing the front part of the transducer housing.

ZW

J2

J1

Fig 4. Marking of terminals for the connection of external signals

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Fig. 5. Way of electrical signal connection

Transducer is equipped with two LED indicator: RX (green color) , TX (red color), which indicates the state of RS-485 communication lines. Indicators works only first 60 sec after power is on or after switching “ZW” jumper (section 7).

4.3. Assembly

On the beginning one must separate front part of housing from back part of housing with printed circuit board using flat screwdriver as shown on Fig. 6.

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Fig. 6. Disassembly housing method

Back part of housing is equipped with hole at the middle of housing through which electrical cords should be passed. Then back part of housing should be screwed on to the wall. Electrical cords should be passed through the hole on the printed circuit board (Fig. 7) and connected to the screw connectors with the right way (Fig. 5)

Fig. 7. The way of assembly electrical cords

After connecting cords and pushing the front part of housing transducer is ready to work.

To connect the input signals in an environment with high interference, one must apply shielded wires. The shield must be connected to the nearest PE point from the feeder side.

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5. SERVICING

After connecting cords, closing the housing, and connecting to the supply, the transducer is ready to work with manufacturer’s settings

(table 2). The transducer can be programmed through the RS-485 interface.

One can program following parameters in the transducer:

- communication parameters

- averaging time of the measurement

There is the possibility to connect the transducer through another transmission media, like: ETHERNET, USB, using LUMEL S.A.’s converters.

5.1. Messages after supply is switched on

After connecting external signals and switching the supply on, the transducer indicates its ready to work by switching on two LED indicators RX(green color) i TX(red color). After about 5 seconds, the transducer automatically switches to the mode in which it measures and converts into the digital value.

5.2. Functions of the P19 transducer l measurement of ambient temperature and relative humidity, l calculation of chosen physical quantities (dew-point temperature,

absolute humidity), l memory storage of maximal and minimal values for each of the

measured and calculated value, l programming of the measurement averaging time, l RS-485 interface servicing in the MODBUS protocol, in RTU mode.

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5.2.1. Calculated values

Based on measured temperature and relative humidity the P19 transducer calculates dew-point and absolute humidity from the following relations.

DP → dew point:

DP=

T n m

RH

10000 . A

- 1

AH → absolute humidity: where:

AH= 2.1668

.

T → measured temperature [oC]

RH → measured relative humidity [%]

P ws

.

RH

100 . (T + 273.2)

DP → dew-point temperature [oC]

P ws

→ pressure of the satured water vapor

(water vapor pressure) [mbar]

AH → absolute humidity [g/m3]

Table 1

Coefficients used for the dew-point calculations

T [ o C] A m Tn

< 0

0 … 50

6.119866

6.1078

50 ...100

5.9987

7.926104

7.5

7.3313

250.4138

237.3

229.1

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5.2.2. Default parameters

Table 2 shows the default parameters of P19 transducer.

These settings can be restored using the RS-485 interface by writing into the 4009 register the value „1”.

Table 2

Parameter description

Address

Baud rate

Mode

Averaging time

Parameter address

4001

4002

4003

4005

Default value

1

9600

RTU 8N2

30 [s]

When standard communication parameters have been changed and the new configuration has been lost, one can set temporary parameters by switching the jumper marked with the symbol “ZW” (section 7).

6. MODBUS PROTOCOL ON RS-485 SERIAL PORT

Digital P19 transducers are equipped with serial RS-485 link port with implemented MODBUS protocol to enable digital communication between computer systems and other devices which have

MODBUS Master functions implemented. The implemented protocol is in compliance with thePI-MBUS-300 Rev G Modicon Company specification.

6.1. Serial interface connection

Standard RS-485 port allows direct connection of up to 32 devices on a single serial link with a length of 1200 m (at a baud rate of 9600 b/s). To connect more devices it is necessary to use additional intermediate-separating devices.

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Interface line location are shown in the figure 5. To obtain a correct transmission it is necessary to connect the A and B line parallel with their counterparts in other devices. To connect to the PC, the RS-485 interface card or the converter, e.g. PD10 is required.

6.2. Description of the MODBUS protocol

The implemented protocol is in compliance with the PI-MBUS-

300Rev G Modicon Company specification. Parameters of the transducer serial link : transducer address baud rate: working modes: maximal response time:

1..247

4800, 9600, 19200, 38400, 57600 [b/s]

RTU: 8N2, 8E1, 8O1, 8N1

500 ms

The configuration of serial link parameters consists on settlement of baud rate, device address and protocol (working mode).

Note: Each transducer connected to the communication network must

have: l unique address, different from other devices connected to

the network, l the same baud rate and information unit type (working

mode).

6.3 Description of implemented MODBUS functions

Functions of the Modbus protocol implemented in P19 transducer:: l 03 (03h) – Read Holding Registers l 04 (04h) – Read Input Registers l 06 (06h) – Write Single Register

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l 16 (10h) – Write Multiple registers l 17 (11h) – Report Slave ID.

Read Holding Registers (code 03h)

Example 1. Reading two float(32 bits) registers, first register address is 1D4Dh (7501) , register values (7501, 7502): 25.68, 20.25.

Request:

Table 3

Device address

01h

Function

03h

Register address

B1

1Dh

B0

4Dh

Number of registers

B1

00h

B0

02h

CRC

5270h

Response:

Table 4

1DB0h (7501) 1DB1h (7502)

CRC

Device address

Number of bytes B3 B2 B1 B0 B3 B2 B1 B0

01h 03h 08h 41h CDh 70h A4h 41h A2h 00h 00h 83D0h

Example 2 . Reading two float 32-bit registers (7501,7502) located in 2x2 following 16-bit registers (7002, 7003, 7004, 7005), first register address is 1B5Ah (7002) – 32-bit register values : 25.68, 20.25.

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Request:

Table 5

Device address

Function

Register address

Number of registers

CRC

01h 03h

B1

1Bh

B0

5Ah

B1

00h

B0

04h 62FEh

Response:

Table 6

Register value

1B5Ah

(7002)

Register value

1B5Bh

(7003)

Register value

1B5Ch

(7004)

Register value

1B5Dh

(7005)

CRC

Device address

Number of bytes

Register 7501 (32 bit) value

Register 7502 (32 bit) value

B3 B2 B1 B0 B3 B2 B1 B0

01h 03h 08h 41h CDh 70h A4h 41h A2h 00h 00h 83D0h

Example 3. Reading two float 32-bit registers (7501,7502) located in

2x2 following 16-bit registers (6002, 6003, 6004, 6005), first register address is 1772h (6002) - 32-bit register values : 25.68, 20.25.

Request:

Table 7

Device address

Function Register address

Number of registers

CRC

B1 B0 B1 B0

01h 03h 17h 72h 00h 04h E1A6h

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Response:

Table 8

Register value

1B5Ah

(7002)

Register value

1B5Bh

(7003)

Register value

1B5Ch

(7004)

Register value

1B5Dh

(7005)

CRC

Device address

Number of bytes

Register 7501 (32 bit) value

Register 7502 (32 bit) value

B1 B0 B1 B0 B3 B2 B1 B0

01h 03h 08h 70h A4h 41h CDh 00h 00h 41h A2h E411h

Write Single Register (code 06h)

Example 4. Writing value “3” to the register 0FA1h (4001)

Request:

Table 9

Device address

Function Register address

Number of registers

CRC

B1 B0 B1 B0

01h 06h 0Fh A1h 00h 03h 983Dh

Response:

Table 10

Device address

Function Register address

Number of registers

CRC

B1 B0 B1 B0

01h 06h 0Fh A1h 00h 03h 983Dh

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Write Multiple registers (code 10h)

Example 5. Writing value “3” and “4” to registers FA1h (4001) and

FA2h (4002)

Request:

Device address

Register address

Number of registers Num- ber of bytes

Table 11

Register value

(4001)

Register value

(4002)

CRC

B1 B0 B1 B0 B1 B0 B1 B0

01h 10h 0Fh A1h 00h 02h 04h 00h 03h 00h 04h 8828h

Response:

Table 12

Device address

Function Register address

Number of registers

CRC

B1 B0 B1 B0

01h 10h 0Fh A1h 00h 02h 133Eh

Report Slave ID (code 11h)

Example 6. Report slave ID

Request: Table 13

Device address

Function

CRC

01h 11h C02Ch

Response:

Table 14

Number of bytes

Device state

Variable bytes depending on device firmware ver. And serial number (neg. ver. 0.95, serial number. 13040001)

CRC

01h 11h 08h D0h FFh 00h 95h 40h 01h 80h 0Dh DFC3h

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6.4 Register map

In the P19 transducer the data is stored in 16- and 32-bit registers. The process variables and parameters of the device are stored in the different address space depending on the variable type. The bits in the 16-bit registers are numbered from the least significant to the most significant (b0 … b15). The 32-bit registers (4 Bytes) contain floatingpoint values in IEEE-754 standard. Bytes sequence: B3 B2 B1 B0 – the most significant byte is sent as the first one. 16-bit registers which represents 32-bit values on a two following registers are multiplied at different address field with different bytes (word) order. Registers

6000...6024 (B1, B0, B3, B2) , Registers 7000...7024 (B3, B2, B1, B0).

Register map of the P19 transducer is shown in Table 15.

Note:

All the given addresses are physical addresses. In some computer programs logical addressing is applied, then the addresses should be increased by 1.

Table 15

Address range

Value type

Description

4000

- 4011 integer

(16 bits)

The value is located in the 16-bit register

6000-6024 float

(32 bits)

7000-7024 float

(32 bits)

7500-7512 float

(32 bits)

The value is located in two following 16-bit registers. Registers contain the same data as 32-bit registers from the area 7500-7512.

Registers are readout type only. Byte order

(B1, B0, B3, B2)

The value is located in two following 16-bit registers. Registers contain the same data as 32-bit registers from the area 7500-7512.

Registers are readout type only. Byte order

(B3, B2, B1, B0)

The value is located in the 32-bit register.

Registers contain measured and calculated data by the transducer. Registers are readout type only. Byte order (B3, B2, B1, B0)

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6.5 Read/Write registers

Table 16

Description

4000 Identifier r 208 Identifier of the P19 transducer

4001 Address

4002 Baud rate of the RS-

485 link r/w r/w

4003 Transmission mode of the RS-

485 link r/w

4004 Acceptation of RS-

485 link parameter changes

4005 Averaging time r/w r/w

1...247

Device address

0...5

Value

0

Description

4800 bit/s

1

2

3

9600 bit/s

19200 bit/s

38400 bit/s

0...3

0...1

4 57600 bit/s

Value Description

2

3

0

1

RTU 8N1

RTU 8N2

RTU 8E1

RTU 8O1

Value Description

0 no changes

1 acceptation of changes

6...3600

Measurement averaging time [s]

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4006 Erasing of extremes

4007 Status register r/w r/w

0...1

-32768...

32767

Value Description

0

1 no changes

Erasing of min and max value

Transducer status. Describe current state and device configuration. Bits representing specific events.

Value bit ‘1’ means that specific event occurred.

Bit15 Supply reset, writing value

-32768 ( 8000h ) clears status bit

Bit14

Bit13

Calibrations parameters error

Incorrect transducer parameters – new parameters required unused Bit12

Bit11

Bit10

Bit9

Bit1

Bit0 unused

Min/max erasing status, writing value 1024 ( 400h ) clears status bit

Temporary communication parameters set (short circuit

„ZW” jumper) unused Bit8

Bit7 Communication with sensor error

Bit5,6 unused

Bit3,4 unused

Bit2 Exceeding of measurement averaging time unused unused

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4008 Firmware ver.

4009 Restore default parameters r r/w

1...999

Firmware version x100

0...1

Value Description

0 no changes

1 Force restoring default parameters (value of register will automatically change to “0’)

4010 reserved

4011 reserved

6.6 Read only registers

Name

Read

(r)/

Write

(w)

Unit

Table 17

Description

7000/6000

7002/6002

7004/6004

7006/6006

7008/6008

7010/6010

7500

7501

7502

7503

7504

7505

ID

T

RH

DP

AH min T w w w w w w

o o o

C

%

C g/m

3

C

P19 identifier

Measured temperature

Measured relative humidity

Calculated dew point

Calculated absolute humidity

Min. measured temperature

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7012/6012

7014/6014

7016/6016

7018/6018

7020/6020

7022/6022

7024/6024

7506 max T

7507 min RH

7508 max RH

7509 min DP

7510 max DP

7511 min AH

7512 max AH w w w w w w w o o o

C

%

%

C

C g/m

3 g/m

3

Max. measured temperature

Min. measured relative humidity

Max. measured relative humidity

Min. calculated dew point

Max. calculated dew point

Min. calculated absolute humidity

Max. calculated absolute humidity

7. EMERGENCY RESTORATION OF RS-485 PARAMETERS

When standard communication parameters have been changed and the new configuration has been lost, one can set temporary

RS-485 parameters by switching jumper marked with the symbol „ZW”

(Fig. 4.) Temporary RS-485 parameters are shown below: l l l address baud rate mode

247

9600 kb/s

RTU 8N2

The changes of parameters must be made before removing the jumper, otherwise the device will return to its previous configuration.

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8. TECHNICAL DATA

Basic parameters:

- relative humidity range

- relative humidity measurement

accuracy

- hysteresis of measuring

relative humidity

- temperature range

- temperature measurement

accuracy

- calculated values

RS-485 interface:

- protocol

- baud rate

- mode

- maximal response time

Rated operating conditions:

- supply voltage

- power consumption

- ambient temperature

- storage temperature

- relative humidity:

- warm-up time

- insured protection grade

ensured by the housing

- mounting

- weight:

- dimensions

0...100 %

1

±3% in range 10...90%

±5% for the remaining range

± 1%

– 20...60 °C

2

±0.6

o

C in range 10...40

o

C

±1.0

o

C for the remaining range absolute humidity (a) [g/m

3

] dew point (Td) [°C]

MODBUS slave

4800, 9600, 19200, 38400,

57600 bit/s

RTU: 8N2, 8E1, 8O1, 8N1

500 ms

9...24 V a.c. / d.c.

< 0.3 VA

– 20...23…60 °C

– 30...23…85 °C

< 95%

1

<15 min.

IP 20 on the wall

<0.2 kg

120 x 80 x 25 mm

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working position: according Fig. 2.

Galvanic isolation

- between supply and RS-485 interface 1 kV

Electromagnetic compatibility:

- disturbance immunity

- disturbance emission acc. to EN 61000-6-2 acc. to EN 61000-6-4

Security requirements acc. to EN 61010-1

- installation category III

- pollution grade

- phase-to-earth working voltage

- altitude above sea level

2

50V

< 2000m

1

- In case of condensation of water vapor on the sensor surface,

the error measurement does not exceed the basic error till

the moment of drying up the sensor structure.

2 - The absolute temperature measurement range is -30...85°C,

but beyond the basic range, the measurement class is not

guaranteed.

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9. ORDERING CODE

Table 18

P19 - XX X X

Version: standard custom-made*

Language: polish english other

Acceptance tests: without extra quality requirements with an extra quality inspection certificate acc. to customer’s requirements*

00

XX

P

E

X

0

1

X

*After agreeing with the manufacturer

Example of Order:

The code: P19 - 00E0 means:

P19 – humidity and temperature transducer

00 – standard version

E – English language version

0 – without additional quality requirements.

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LUMEL S.A.

ul. Słubicka 1, 65-127 Zielona Góra, Poland

Tel.: (48-68) 45 75 100

Fax: (48-68) 45 75 508 e-mail:[email protected]

http://www.lumel.com.pl

Export Department :

Tel.: (48-68) 45 75 302

Fax: (48-68) 32 54 091 e-mail: [email protected]

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