7-7. General maintenance
• Compressor coil insulation inspection
Using an appropriate device, measure the insulation value between a winding and another winding in the compressor,
and the winding and ground contact area. Before supplying power to the compressor, this test should be conducted.
Before proceeding the procedure described below, check whether the auxiliary power to the chiller is stopped.Also, make
sure to check whether the chiller's power switch is 'OFF'.
The insulation resistance value test should follow the following steps.
- Interrupt the auxiliary power switch.
- Open the compressor wiring box
- Disengage compressor power supply line
- Disengage compressor heating wire
- Measure the resistance
This test should not be implemented in a vacuum state. Otherwise, it may cause damage to the coil winding.
When the test voltage is 500V, the resistance should be at least 3MΩ.
After measurement, restore the connections following the schematic.
Especially, a special attention should be taken to align the compressor's motor wire connector with the upward rev-
olution direction measurement connector.
Due to the compressor's characteristics, the phase connection should be made very accurately.
Otherwise, the compressor will be damaged. So, please give a special attention to connection work.