YZ Engineering Guide
Form: 161.01-EG1 (0618)
21
ELECTRICAL CONSIDERATIONS
Unit input conductor size must be in accordance with applicable electrical codes, for the unit full load amperes (FLA).
Please refer to the submittal drawings for the FLA and Minimum Current Ampacity (MCA) specific to each application.
Flexible conduit should be used for the last several feet to the chiller in order to provide vibration isolation. The table
below lists the allowable variation in voltage supplied to the chiller. The unit nameplate is stamped with the unit voltage
and frequency.
Voltage Variations
Frequency
Rated
Voltage
(Volts)
Nameplate
Voltage
(Volts)
Operating
Voltage (Volts)
Min
Max
60 Hz
460
460
414
508
400
400
360
440
380
380
342
423
50 Hz
415
415
374
456
400
400
360
440
380
380
342
423
Copper Conductors
-
Only copper conductors should be connected to compressor motors and starters. Aluminum
conductors have proven to be unsatisfactory when connected to copper lugs. Aluminum oxide and the difference in
thermal conductivity between copper and aluminum cannot guarantee the required tight connection over a long period
of time.
Displacement Power & Factor Correction Capacitors
- The VSD provides automatic displacement power factor
correction to a minimum of 0.95 at all operating conditions, so additional capacitors are not required.
Branch Circuit Overcurrent Protection
- The branch circuit overcurrent protection device(s) should be a time-delay
type, with a minimum rating equal to the next standard fuse/breaker rating above the calculated value. Refer to the
submittal drawings for the specific calculations for each application.
