10. CHECKING ELECTRICAL COMPONENTS
10-1. Measurement of Insulation Resistance
Ground wire
Clip
●The insulation is in good condition if the resistance exceeds 2M½.
Probe
10-1-1. Power Supply Wires
Clamp the ground wire of the power supply wires with the lead clip of the insulation resistance tester and measure the resistance by placing a probe on either of the power wires. (Fig. 1)
Insulation |
|
tester | Fig. 1 |
Terminal plate
Then measure the resistance between the ground wire
Probe
and the other power wire. (Fig. 1)
10-1-2. Indoor Unit
Clamp an aluminum plate fin or copper tube with the lead clip of the insulation resistance tester and mea- sure the resistance by placing a probe on each termi- nal screw on the terminal plate. (Fig. 2)
Note that the ground line terminal should be skipped for the check.
| Clip |
Copper | Insulation |
tube or | tester |
metallic part |
|
Fig. 2
10-1-3. Outdoor Unit
Clamp a metallic part of the unit with the lead clip of the insulation resistance tester and measure the resis- tance by placing a probe on each terminal screw where power supply lines are connected on the terminal plate. (Fig. 2)
Disconnect the lead wires of the desired electric part from terminal plate, capacitor, etc. Similarly disconnect the connector. Then measure the insulation resistance. (Figs. 3 and 4)
NOTE
Refer to Electric Wiring Diagram.
If the probe cannot enter the poles because the hole is too narrow then use a probe with a thinner pin.
Probe
Clip
Copper tube or metallic part
Insulation |
|
tester | Fig. 3 |
|
From fan motor, compressor and other parts
Metallic | Probe |
part |
|
Clip |
|
Insulation | Fig. 4 |
tester |
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