GE Industrial Solutions AF-600 FP High Power (460V_575V 150HP and above) User Manual
Page 95
9.
Measure pins 1 and 2 of each test connector. Each reading should be approximately -9 VDC, indicating all IGBTs are turned off.
10.
Apply the run command to the frequency converter and 30 Hz reference.
11.
If using a DVM, measure pins 1 and 2 of each connector. Waveform to IGBTs is a square wave that goes positive to 14 VDC and negative to -9 VDC.
Average voltage read by DVM should be 2.2 to 2.5 VDC.
130BX75.10
1
2
3
4
5
6
7
8
9
10
11
12
Illustration 6.17: Gate Drive Card Test Connectors
1
Pin 1
7
MK450
2
MK850 (brake)
8
MK103 (V)
3
MK105 (brake option)
9
MK550
4
MK250
10
MK650
5
MK102 (U)
11
MK104 (W)
6
MK350
12
MK750
When using an oscilloscope, the readings should appear as in Illustration 6-18.
Illustration 6.18: Gate Signal Waveform from Gate Drive Card. IGBT Gate Signal measured on the Gate Drive Card: 5 volts per division vertical scale,
50 microseconds per division time scale. Unit running at 30 Hz.
An incorrect reading of a gate signal indicates the gate drive card is defective or the signal has been lost prior to it arriving at the gate card. The gate signals can
then be checked with the signal test board to verify their presence from the control card to the power card as follows.
AF-650 GP and AF-600 FP High Power Service Manual
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