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ICE CFA1012A I&O Manual 01/2021 New
C. Check Rated Voltage at Terminal Block for Imbalance before starting of Unit.
❒
208/230V 1 Phase
❒
208/230V 3 Phase
❒
460V 3 Phase
❒
380V 3 Phase 50Hz.
❒
575 3 Phase 60 Hz.
Measured Line to Line Volts L1&L2_______V.
L1&L3 ________V.
L2&L3______V.
(L1&L2 + L1&L3 + L2&L3)/3 = Avg. Voltage = _______________
Max. Deviation from avg. voltage = ______________volts
Voltage imbalance = (100 x Max. Deviation)/avg. Voltage = ___________%
A voltage deviation greater than 2% with the unit running should be addressed and corrected. Excess
voltage deviation can cause the compressor to overheat and to operate inefficiently.
Example: Maximum Deviation from Average Voltage X 100 (for Percent)
Average voltage
Measured Voltages:
L1 & L2 = 241 Volts
L1 & L3 = 243 Volts = 717 / 3 = 239 Average Voltage
L2 & L3 = 233 Volts
239 - 233 = 6
100 x 6/239 =2.5% Voltage Unbalance
Three phase units only check fan & compressor rotation.