Thermal Dynamics ULTRA-CUT 200 XT, Operating Manual

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ULTRA-CUT 200 XT
A-68 APPENDIX Manual 0-5304
239 AC Voltage High
Voltage OK -- At power up the System Bias board measures the input voltage and determined if it is within the
range of voltage set by the J16 jumper. See section 231-236 Inverter VAC Mismatch Troubleshooting step 1.a
for details of the jumper. Normally when the input voltage is OK the System Bias board turns on a relay K1
on the left die of the board to apply power to the T1 Auxiliary transformer. D44, a green “Transformer ON”
LED, will light when K1 is energized. T1 provides power to the gas controls and the TSC 3000 as well as the
pumps and fans.
Voltage High -- If the AC voltage is determined to be too high it lights D4, ACV HIGH, a red LED on the System
Bias board, and sets the signal “AC V HIGH b” on J62-6 to a “high” about 24VDC (normal for a “low” here is
10-14VDC). To prevent the possibility of excessive voltage applied to several items (gas controls, pumps, fans
etc.) K1 is opened removing power from T1 and D44 goes off. If it’s more than a momentary glitch the gas
controls and the TSC 3000 (if used) will reset. Communication with the cutting table may be interrupted. With
the DFC 3000 Auto Gas Control and perhaps the cutting table control, the process will have to be reloaded.
D4 is on and the signal “AC V HIGH b” is high only while the voltage is actually high. The signal “AC V HIGH
b” does not latch on.
If the fault is E239 that means it is currently active, that is, currently detected as being too high. If it’s L239 that
means the voltage too high previously but it is not too high now. Applying START will clear the fault unless
it becomes active again.
The voltage that triggers an AC Voltage High fault is above 550V for 480VAC line; above 470V for a 380, 400 or
415V nominal line; above 270V for a 208 or 230VAC line.
Possible causes:
• Incoming voltage is or was too high.
• Bad connection at J62 or J27
• Bad connection at J61 jumper
• System Bias board defective
• CCM defective.
Troubleshooting:
1. If the fault is L239 applying START will clear the fault unless it becomes active again. An occasional prob-
lem may be due to incoming voltage swells (voltage increases lasting from ½ cycle to as much as a minute).
Usually, if the plasma is at fault the problem will be present all the time.
2. It is unlikely that an open connection on the J61 jumper would result in a 239 fault, more likely to be a Volt-
age Mismatch fault. However, if it’s intermittent at exactly the right time, perhaps not fully plugged in, it
could possibly show up as 239. Check J61.
3. If the incoming voltage is OK and the problem persists it may be the System Bias board, the CCM or the
connection between J62 and J27.
a. If the incoming voltage is OK and D4 is on or signal “AC V HIGH b” on J62-6 is “high” (about 24VDC,
relative to TP1 or J62-8 ) the System Bias board is defective.
b. If D4 is not on and the signal “AC V HIGH b” on J62-6 is “low” (about 10-14VDC, relative to TP1 or J62-
8) then System Bias is OK and problem is in the CCM.
c. If J62-6 is near zero volts there may be bad connection between J62-6 and J27-6 or J62-7 and J27-6.