Upper Bank Hv Switch Section (3) And Vias To Ground (4) - GE LOGIQ E9 Service Manual

PROPRIETARY TO GE
D 5180483-100, R . 7 LOGIQ E9 P S M
IRECTION EV ROPRIETARY ERVICE ANUAL
7-9-19-7 Visual Inspection of Board (cont'd)
Troubleshooting Step 1 - Upper Bank of HV FET Section (cont'd).
If no Visual Damage is found on Upper Bank of Transmitter Channels
Measure resistance from output of HV feed resistors R97 and R131 to ground.
NOTE: Measured resistance of a good board should be ~ 90 - 110K ohms, with a calibrated ohm meter.
If measured resistance is less than ~ 90 - 110K (typically 5 ohms or less) this is indicative of a transmit
transformer with a primary to secondary short.
Figure 7-194 Upper Bank HV Switch Section (3) and Vias to ground (4)
Measure from these vias to ground (4) to test for possible transmit transformer short on the upper bank.
7 - 290 Section 7-9 - Troubleshooting Tips