Tweco 400 Ultra-Cut(May 2014) - Manual (Page 191)

ULTRA-CUT 100 XT/200 XT/300 XT/400 XT
Manual 0-5302 APPENDIX A-63
3. If the work current sensor is defective it could be telling the relay board (and thus the CCM) that there is already a trans-
ferred arc so no need for pilot. D12, a green LED on the Relay board, is on if work current is detected. If D12 is not on
skip to step 5, otherwise disconnect J1, the work sensor connector. If D12 is still on the Relay board is defective.
4. If D12 goes out when J1 is disconnected, plug it back in and measure voltage from TP1 (common) to J1-1, should be
positive 12-15VDC. Now measure J1-2, should be negative 12-15VDC. Now measure J1-3, should be 0 +/- 0.05V. If
any of these are wrong disconnect J1 and measure again (on the relay board, not the harness). If still wrong the relay
board is defective. Otherwise it’s the work sensor.
5. Pilot Enable signal comes from the CCM on pin 15 of the 40 pin ribbon cable between the Relay board (J4) and the CCM
(J23). It should be low, less than 2V relative to TP1 on either the CCM I/O board or the Relay board. You can also measure
this on TP11 of the I/O board. If the signal does not go low when the pilot should be enabled at the end of preflow time
then the CCM is probably defective. You can also jumper TP11 on the CCM I/O board to TP1, also on the I/O, to see if
that will light D7, the Pilot Enable LED, on the Relay board. If it does, that further confirms the CCM is bad. If jumping
TP11 to TP1 does not light D7 on the Relay board, the problem is likely the Relay board or possibly the ribbon cable.
103 Lost Pilot
Code 103 occurs when Pilot has ignited as sensed by the pilot current sensor on the Pilot board , but went out on its own
while CNC Start is still active before the pilot timeout (85 ms. or 3 sec.).
Possible causes:
• Preflow gas pressure too high, for manual gas controls check cut charts for proper setting. For DFC 3000 check that
the process is correct for the consumables.
• Cutting current set too low for the torch parts being used. Pilot current level is automatically set based on the cutting
current. A low cutting current results in a lower pilot current that may not be able to sustain a pilot for higher current
torch parts.
• Remote Analog Current Control switches set wrong can also result in lower than normal pilot current setting. See
section on these switch settings under next section for code 104.
• Broken torch pilot wire.
• Defective Inverter module puts out less current than it’s set for.
104 Transfer Lost
Arc transferred to metal for at least 50 ms. then went out.
Causes for 104 code:
• Cut demand set much lower than recommended for torch parts, i.e. 100A consumables in torch but cut current set for
30 or 50A (or zero). Current may be too low to keep arc on.
• Torch standoff too high for cutting process being used.
• Plasma gas flow too low due to a leak somewhere between the plasma regulator or the DPC 3000 and the torch. Check
for leaks.
• Remote analog current control switches set wrong.
o If remote analog current control is being used, SW8-2 (CCM CPU PCB) is on and SW11 (CCM I/O PCB) is set to
“A” (down) position, but no analog voltage connected to TB1-10 or J15-30 (CNC cable) then cut demand will be
zero, pilot will be weak, depending on torch height it may still transfer but will immediately go out.
o If remote analog current control is not being used but either SW11 is set to the down position or SW8-2 is on also
results in zero cut demand.
o If system is Auto-Cut XT, current control is an analog voltage from the GCM 1000 XT or the AC 200 XT front panel
pot. The current control setting will be shown on the front panel 4 digit display. SW8-2 should be off and SW11
set to up position. With pot at max, check for 3.3V on CCM I/O PCB TP9 (TP1 common). While turning the pot
toward minimum TP9 voltage should vary linearly to zero V.