GE Industrial Solutions AF-600 FP High Power (460V_575V 150HP and above) - Manual (Page 85)

Ohm test of fans
1. Measure between terminals 3 and 5 of power card connector MK107. It should read approximately value D in Table 6-1.
Incorrect reading
For fans without an inductor, replace the fan. For frequency converters with a fan and inductor, isolate the fault between the fan and the inductor
as follows.
1a Disconnect CN3 and measure the resistance between pins 1 and 2 on the fan side of the connector. Reading should be approx 4 ohms. If
incorrect, replace fan.
1b Disconnect CN4 and CN5. Measure the resistance across the inductor. Reading should be less than 1 ohm. If incorrect, replace the inductor.
2. Measure between terminals 11 and 13 of power card connector MK107. For units with one top mounted fan, a reading of 400 ohms is expected. For
units with two door mounted fans, a reading of 200 ohms is expected.
Incorrect reading
For units with one top mounted fan, replace the fan. For units with two door mounted fans, isolate the faulty fan as follows.
a. Disconnect the wiring from the fan terminals.
b. Read across the fan terminals on each fan. A reading of 400 ohms is expected. Replace any defective fans.
Illustration 6.11: Fan and DC Bus Fuse Locations
1 Power card 4 Mounting plate
2 DC bus fuse 5 MK107
3 Fan fuse
AF-650 GP and AF-600 FP High Power Service Manual
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