Tweco 400 Ultra-Cut(May 2014) - Manual (Page 200)

ULTRA-CUT 100 XT/200 XT/300 XT/400 XT
A-72 APPENDIX Manual 0-5302
Troubleshooting:
1. If System Bias board has either the wrong jumper or is defective it will call out the first inverter section, code 231, because
all the inverters won’t match the incorrect signal and 1A is checked first.
a. For the jumper Wire #48 should be connected from J61-1 to:
i. J61-2 for 208-230 VAC
ii. J61-3 for 400 VAC
iii. J61-4 for 480 VAC
Check for proper connection and continuity.
b. System Bias may be defective reporting the wrong voltage ID. On the output of the System Bias board at J62 measure
relative to TP1 or ( J62-8, 24VDC_RET) to J62-12 for signal /VAC_IDAb and J62-14 for signal /VAC_IDBb. The 2
signals should read according to this table. “0” = 10-12V; “1” = 24V.
signal 230V 400V 480V ERR
/VAC_IDAb 0 1 0 1
/VAC_IDBb 0 0 1 1
2. Defective inverter, ribbon cable or CCM.
a. On the inverter section swap the ribbon cable of the inverter section whose fault was indicated with that of a different
inverter section. If fault remains unchanged, still calls out the original inverter section, the problem is with either
ribbon cable or CCM. If fault changes to the different section, the one the ribbon cable was swapped with, then it’s
the inverter that’s defective.
b. If the fault remained unchanged in Step A, on the inverter end, put the ribbon cables back in their original positions.
Now swap suspect ribbon cable with another one on the CCM. If the fault now moves to a different section it’s the
ribbon cable. If it remains with the original section the problem is the CCM.
237 Too Few Inverters Found
There must be a minimum of 2 inverter sections present to operate. We know the ribbon cable for inverter section 1A is
connected or else we would have code 224. During the power up sequence, before power is connected to the inverters, the
CCM does a continuity test through the ribbon cable to see if an inverter is connected. If it doesn’t see continuity with at
least one other inverter it assumes none are connected.
Possible causes:
• Ribbon cable disconnected or defective.
• Inverter defective
• CCM defective.
Troubleshooting:
1. Check that all cables are connected, latches locked down, at both the inverter and CCM ends.
2. If this fault occurs it’s most likely on a 100A unit which only has one section (1B) in addition to the 1A section. If there
were 2 or more additional sections it’s extremely unlikely all ribbon cables or CCM connectors would be defective.
a. Swap the ribbon cables of the inverter section 1A and 1B. If fault remains unchanged, still 237, problem is with either
ribbon cable or the CCM. If fault changes from 237 to 224 indicating inverter 1A missing, then it’s the inverter that’s
defective.
b. If the fault remained unchanged in step a., on the inverter end put the ribbon cables back in their original positions.
Now swap suspect ribbon cables on the CCM. If the fault now changes it’s the ribbon cable. If it remains the same
it is the CCM.
c. If there are 2 or more ribbon cables in addition to the one on section 1A then CCM is seeing none of them connected
which indicates the CCM is faulty.