Infinite TRANSTECTOR 700 AV/T Series Owner's Manual page 25

TROUBLESHOOTING (continued)
CHECK THE SCR SNUBBER CARD
1. Three components make up the SCR snubber. (Resistors, MOVs and Capacitors). Check for
open resistors. Check MOVs for shorts, they should read high resistance when ohm meter is
placed across them. Resistance check each capacitor. The DC resistance across the snubber
capacitor should look capacitive-that is high resistance after the meter charges the capacitor.
If it measures open or shorted, replace the snubber card.
2. RE-CONNECT SEMICONDUCTOR FUSES, ALL WIRES AND FANS.DOUBLE CHECK THAT
ALL CONNECTIONS ARE SECURE.
DO NOT CONNECT TB1, TB2, and TB3 CONNECTORS FROM THE CONTROL CARDS
#414921 YET!
CHECK CONTROL CARD AND FILTER CARD
1. Verify input to the Power Processor matches the units specification. Also verify correct control
board #414921 jumper setup in Appendix A, Page 40.
2. Disable the over/under voltage shutdown card #35867 (optional card) by removing connectors
K1 and K2 on the card.
3. Turn on AC input breaker to unit.
IMPORTANT: Extreme caution must be taken when measuring voltages on Molex connectors.
Do not press meter leads into connectors or bend connectors back.
4. Measure the following voltages on wires feeding the TB1 Molex connector to the control card
on all 3 phases.
Pins 1 & 3 = 4-6 VAC.
NOTE: When the connector is plugged in this voltage is around 3 VAC.
Pins 7 & 8 = 120 VAC
If this voltage is incorrect or not present, then check the fuses associated with the filter card or replace
filter card and re-check voltages.
5. Turn main AC circuit breaker off. Plug in connectors TB1 and TB3 ONLY!!! on the control card
#414921 on all 3 phases.
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