Thermal Dynamics ULTRA-CUT 200 XT, Operating Manual

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ULTRA-CUT 200 XT
Manual 0-5304 APPENDIX A-67
237 Too Few Inverters Found
There must be a minimum of 2 inverter sections present to operate. We know the ribbon cable for inverter sec-
tion 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 sec-
tion. 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.
238 System Bias voltage identification is invalid.
At power up the System Bias board measures the input voltage and sends signals to the CCM indicating which
range of voltage it has detected. See section 231-236 for details. If one of the 3 voltage ranges, 208-230V, 380-
415V or 480V isn’t identified then both ID signals are high resulting in an invalid signal.
Possible causes:
• Unit is connected to voltage below the 208-230V range or above the 480V range. (unlikely unless there is
a problem with the incoming voltage.)
• Defective System Bias board
• Bad connection between System Bias output J62 and CCM input J27 on the I/O board.
• Defective CCM
Troubleshooting:
1. Measure all 3 phases of the input voltage and confirm they are within the tolerance specified in the unit
manual.
2. Refer to section 231-236 Inverter VAC Mismatch and perform troubleshooting in step 1.b. If the 2 signals
don’t match the incoming voltage, if both are high, then the System Bias is defective.
3. If step 2 was OK make the same measurement at J27 on the CCM I/O PCB. If OK here the CCM is defective.
Otherwise inspect the connections at J62 and J27.