Thermal Dynamics ULTRA-CUT 200 XT, Operating Manual

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ULTRA-CUT 200 XT
A-56 APPENDIX Manual 0-5304
8. If “ /RAS ON” signal is low on pin 16 of the 40 pin ribbon cable, relative to TP1 on the CCM I/O board,
during the ignition time then we need to determine if the Relay board is defective. If /RAS ON signal is
not low the CCM or the 40 pin ribbon cable may be defective.
a. If the Relay board RF ON LED, D23, is not on while the /RAS ON signal is low, then the Relay board is
defective.
b. Is D23 is on, measure for 120 VAC on J8-3 to J8-11. If not present the Relay board is defective.
c. If 120 VAC is present at J8 during the ignition time go back and perform steps 2-4.
Troubleshooting Pilot Board problems.
1. The Pilot board is behind the CCM in the AC 300 XT and all Ultra-Cut XTs or on the upper section of the
second inverter module in an AC 200 XT and has two LEDs. The first one, D11, a green LED, indicates the
board has bias power and should be on all the time when the unit is turned on. The second LED, D2, also
green, is on when the pilot is enabled, that is the pilot IGBT switch is turned on. The pilot is enabled near
the end of preflow time and remains on until the transfer is established or for 15 seconds after which a 102
code is displayed. If D2 performs as expected you know the CCM, Relay board and work current sensor
are not causing the problem.
2. Test pilot IGBT operation. D2 on shows the pilot is enabled but you don’t know if the pilot switch (IGBT
transistor) actually closes the circuit. To test attach a jumper, 18 AWG or larger as follows:
a. Ultra-Cut XT or Auto-Cut 300 XT: connect a jumper wire from TB4-7 (arc volts) to TB4-6 (tip volts).
b. Auto-Cut 200 or Pak200i: connect jumper from the negative buss bar by the HF coil to where the pilot
wires attach to the gas fitting on the torch bulkhead panel.
Apply CNC Start. If the pilot switch closes as it should, you’ll get either 106 or 208 fault code within 3-5
seconds. If not, keep the CNC Start on for up to 20 seconds. The front panel DC LED will stay on for 15
seconds then shows 102 code again. This likely indicates the Pilot board is bad but If the XT supply includes
the 1Torch option it could be the W4 contactor is not closing. Go to the 700 group instructions to bypass the
W4 contactor.
3. If D11 on the Pilot board is not on check if the 10 pin ribbon cable is connected between the Pilot board (J42)
and the Relay board (J3). Measure for 24 VDC on the Pilot ribbon cable test connector pin 2 (+) and pin 10
(-). If 24V is present and neither D11 nor D2 lights then the Pilot board may be defective. Pilot board end
of the ribbon cable could also be the cause.
What should happen on the Relay board is LEDs D12, work Current Detected & D11, Pilot Current Detected
should both be off. When you apply START after 2 seconds (Preflow time) D7, Pilot Enable, should come on.
Also D23, RF ON, should come on indicating the Arc Starter is being enabled. Normally D23 would only
be on for a moment until pilot current is detected. Then D11 would be on (and D23 off) until arc transfer or
pilot timeout (15 sec.) Since a pilot has not been detected D11 should not come on.
4. If the work current sensor is defective it could be telling the relay board (and thus the CCM) that there is
already a transferred 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.
5. 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 har-
ness). If still wrong the relay board is defective. Otherwise it’s the work sensor.
6. 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.