Air-Cooled Screw Compressor Chiller Installation, Operation and Maintenance Manual 60 Hertz

IOMM ALS

Electrical Data Notes

1. Allowable voltage limits:

Unit nameplate plus or minus 10 percent.

2. Unit wire size ampacity (MCA) is equal to 125% of the largest compressor-motor RLA plus 100% of

RLA of all other loads in the circuit including control transformer. Wire size ampacity for separate

115V control circuit power is 15 amps for ALS125A through ALS280A.

3. Compressor RLA values are for wire sizing purposes only but do reflect normal operating current draw at unit rated capacity. If unit is equipped with SpeedTrol condenser fan motors, the first motor on each refrigerant circuit is a single phase, 1 hp motor, with a FLA of 2.8 amps at 460 volts (5.6

amps at 208/230 volts). If the unit is not equipped with SpeedTrol, the standard fan motor will be 1

1/2 hp, 3-phase (for ALS070A-280A) with a FLA as shown in the electrical tables. For ALS300A-

425A the standard fan motor will be 2 hp, 3-phase.

4. Compressor LRA for reduced inrush start is for the first winding. If the unit is equipped with

SpeedTrol motors, the first motor on each refrigerant circuit is a single phase, 1 hp motor, with a

LRA of 7.3 amps at 460 volts (14.5 amps at 208/230 volts). If the unit is not equipped with

SpeedTrol, the standard fan motor will be 1« hp, 3-phase with a LRA as shown in the electrical tables.

5. Single point power supply requires a single disconnect to supply electrical power to the unit. This power must be fused.

6. Multiple point power supply requires two independent power circuits on ALS125A-ALS195A,

ALS300-ALS425 and three independent power circuits on ALS205A-ALS280A each with separate fused disconnects and a separate control circuit.

7. All field wiring to unit power block or optional non-fused disconnect switch must be copper.

8. Field wire size values given in tables apply to 75

°

C rated wire per NEC except for ALS185A-

ALS204A and ALS370A, ALS425A for 208V application or as noted.

9. Disconnect switches must be field supplied.

10. All wiring must be done in accordance with applicable local and national codes.

11. Recommended time delay fuse size or circuit breakers (Canadian units only) is equal to 150% of the largest compressor-motor RLA plus 100% of remaining compressor RLAs and the sum of condenser fan FLAs.

12. Maximum time delay fuse size or circuit breakers (Canadian units only) is equal to 225% of the largest compressor-motor RLA plus 100% of remaining compressor RLAs and the sum of condenser fan FLAs.

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