Medium Voltage—Primary Reactor (2.3–6.6 kV). Trane Drives, CVHG, Starters, CVHF, Electrical Components, CVHE, CDHG, CDHF

CTV-PRB004.book Page 35 Sunday, December 18, 2011 6:39 PM

Medium-Voltage Starter Types (2,300–6,600 Volts)

Figure 26. Unit-mounted, across-the-line, medium-voltage starter

1

1. Top-entry power connection

2. Current-limited power fuses

3. Vacuum contactors

4. Low-voltage section

5. Isolation switch

(provision for one lock)

6. Control-power transformer

2

3

4

5

6

Medium Voltage—Primary Reactor (2.3–6.6 kV)

Primary Reactor Starter (2,300–6,600 volts)

One of the most common starters in the industry is the primary reactor. To illustrate a typical starting sequence using a generic (non-Trane) schematic, refer to Figure 27, p. 36 and the starting sequence below.

Starting sequence

1. A “start” signal from the chiller controller energizes the pilot relay (PR).

2. The PR contacts close to energize the start contactor (1M).

3. The 1M contacts close to connect the compressor motor to the line with the motor in series with the reactor.

4. A time delay or current monitoring device initiates transition by energizing the run contactor

(2M).

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CTV-PRB004.book Page 36 Sunday, December 18, 2011 6:39 PM

Medium-Voltage Starter Types (2,300–6,600 Volts)

5. The 2M contacts close to bypass the reactor and connect the compressor motor directly to the line.

Figure 27. Simplified primary reactor wiring diagram

LINE

VOLTAGE

36

1M

1M

1M

OL

PRIMARY REACTOR

80% 65%

50%

2M

OL 2M

OL 2M

MOTOR

F

CPT

F

START-

STOP PR

PR

1M

2M

TRANSITION

Standard features

• Control-power transformer

• Primary and secondary current transformers (CTs)

• Potential transformers (PTs)

• Grounding provisions

• Bolted line-power connections

• Bolted load-side connections for remote starters

• Standard motor protection

Environmental specification

• Designed, developed, and tested in accordance with UL 347

• NEMA 1 enclosure as standard

• Operation from sea level to 6,000 ft (1,829 m)

• Operating ambient temperature range 32°F to 104°F (0°C to 40°C)

• Relative humidity, non-condensing 5% to 95%

• Non-operating ambient temperature range -40°F to 158°F (-40°C to 70°C)

• Voltage utilization range ±10%

Dimensions

Typical dimensions for remote-mounted primary reactor starters are shown in Figure 28, p. 37 .

Unit-mounted primary reactor starter dimensions are shown in Figure 29, p. 37 . Always consult the submittal drawings for as-built dimensions.

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CTV-PRB004.book Page 37 Sunday, December 18, 2011 6:39 PM

Medium-Voltage Starter Types (2,300–6,600 Volts)

Figure 28. Remote-mounted, reduced-voltage starter dimensions

80"

30"

72"

Figure 29. Reduced-voltage, unit-mounted starter dimensions

Top Hat

9.13"

Reduced-Voltage

Section (mounted on the condenser)

60"

27"

26.2"

40"

20"

38"

CTV-PRB004-EN 37