4. Service procedures
4-4 Checking the Electrical Components
(1) Measurement of Insulation
Resistance
• The electrical insulation is acceptable when the | Probe | |
resistance exceeds 1 MΩ. | ||
|
1Power Supply Wires
Clamp the earthed wire of the Power Supply wires with a lead clip of the insulation resistance tester and measure the resistance by placing a probe on either of the power wires. (Fig. 42)
Then measure the resistance between the earthed wire and the other power wires. (Fig. 42)
2Indoor Unit
Clamp an aluminum plate fin or copper tube with the lead clip of the insulation resistance tester and
Clip
measure the resistance by placing a probe on the terminal plate (Fig. 43)
Copper tube or metallic part
Earthed wire
Clip
| Insulation |
| tester |
| 0638_X_S |
Terminal plate | Fig. 42 |
Probe
Insulation tester
0639_X_S
4
3Outdoor Unit
Measure the resistance by placing a probe on the terminal plate in the same manner as explained above 2. (Fig. 43)
4Measurement of Insulation Resistance for Electrical parts
•Disconnect the connector of the desired electric part from terminal plate, P.C.B. Ass’y, etc. (Fig. 44)
•Similarly, disconnect the lead wires from compressor, capacitor, etc. (Fig. 45)
•Measure the resistance in the same manner as illustrated on the right.
Refer to Electrical Wiring Diagram.
NOTE
If the probe does not enter the hole because the hole is too narrow, use a probe with a thinner pin.
Fig. 43
Probe
Clip
Copper tube or metallic part
Insulation tester
0640_X_S
Fig. 44
From fan motor, compressor and other parts.
Metallic | Probe |
part |
|
Clip |
|
Insulation tester
0641_X_S
Fig. 45
SM830043
– 68 –
