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Electrical Maintenance (Rev. 04/03)
56
Troubleshooting the Phase Conversion System
If the electric motor does not run properly, first check the line voltage, the motor contactor, and the motor overload relay. if
these are all acceptable, test the electric motor to narrow down the possible causes for the problem. See the Troubleshooting
Chart for the individual component tests.
Electric Motor Tests
Test 1. Run the motor with three-phase power.
Disconnect the T1, T2, T2A, T3E, and T3F wires from the motor and connect three-phase power directly to the motor. Con-
nect L1 to leads 1 and 7, connect L2 to leads 2 and 8, and connect L3 to leads 3 and 9. Start and run the unit. Check and record
the voltage and current readings in the following chart.
The ideal voltage is 208 to 235 volts ac and the voltage should not vary more than 10% between the sets of wires. If the volt-
ages are out of these ranges, check the power source.
The start current should be approximately 75 amps.
The run current should not exceed 14.5 amps.
The current should not vary more than 10% between wires.
If the run current is higher than 14.5 amps in all three wires, check the suction pressure regulator setting before replacing the
motor. Check the setting of the suction pressure regulator by observing the suction pressure while the unit is running in defrost.
If the suction pressure is higher than 19 psig (131 kPa), the suction pressure regulator must be adjusted or replaced.
Replace the motor if currents are out of these ranges.
Test 2. Run the motor with single-phase power and the phase conversion system connected to the motor.
Remove the electrical connection box cover on the motor, and check and record the current readings in the following chart.
Wires
Voltage
Wire
Start Current
Run Current
L1-L2
L1
L2-L3
L2
L3-L1
L3
Wire
(Motor Lead)
Start Current
Run Current
T1
(1)
T1
(7)
T2
(3)
T2A
(9)
T3E
(2)
T3F
(8)
Summary of Contents for KD-II SR
Page 4: ......
Page 8: ......
Page 13: ...Safety Precautions Rev 04 03 v AEA40...
Page 14: ...Safety Precautions Rev 04 03 vi AEA38...
Page 33: ...Unit Description Rev 04 03 19 1 Evaporator 2 Access Door Rear View Curbside KD II SR 1 2 AEA38...
Page 37: ...Unit Description Rev 04 03 23 Power Receptacle Box KD II SR 50 AEA42...
Page 58: ...Remote Control Panel Features Rev 04 03 44...
Page 112: ...Refrigeration Maintenance Rev 04 03 98...
Page 120: ...106...
Page 146: ...132...
Page 156: ...142...
Page 162: ...148...
Page 170: ...156...
Page 172: ...158...
Page 173: ...159 KD II 30 Schematic Diagram Page 1 of 2...
Page 174: ...160 KD II 30 Schematic Diagram Page 2 of 2...
Page 175: ...161 KD II 30 Wiring Diagram Page 1 of 2...
Page 176: ...162 KD II 30 Wiring Diagram Page 2 of 2...
Page 177: ...163 KD II 50 Schematic Diagram Page 1 of 2...
Page 178: ...164 KD II 50 Schematic Diagram Page 2 of 2...
Page 179: ...165 KD II 50 Wiring Diagram Page 1 of 2...
Page 180: ...166 KD II 50 Wiring Diagram Page 2 of 2...
Page 181: ...167 KD II 50 SR 230 1 60 Wiring Diagram Page 1 of 2...
Page 182: ...168 KD II 50 SR 230 1 60 Wiring Diagram Page 2 of 2...