Tweco 400 Ultra-Cut(May 2014) - Manual (Page 193)

ULTRA-CUT 100 XT/200 XT/300 XT/400 XT
Manual 0-5302 APPENDIX A-65
New for the Auto-Cut XT units is a switch on the rear of the power supply that needs to be set according to the plasma gas.
If using an oxidizing gas (O2 or Air) set it as indicated for those gasses (left if AC 200 XT or up for AC300XT) or if using a
non-oxidizing gas (N2, H35 or other inert gas) set it to the right or down as indicated for those gas types.. This switch adjusts
the range of voltage for the gas type to better protect the torch. A wrong setting could result in false setting of the 108 code.
During piloting and ramping (the time from transfer until the current reaches full cut current), we lower the allowed tip to
electrode voltage to about 80% of that allowed during cutting because the current is lower and the gas flow is lower during
that time.
Causes for 108 code:
• Gas Flow/pressure too low for consumable parts being used.
o If gas source pressure is not well regulated it is possible pressure may be OK at times and drop too low at other
times such as during a cut.
o A leak of the preflow/plasma gas after the pressure/flow control (GCM 2010, DPC, GCM 1000 XT) can reduce the
pressure/flow to the torch because some if it is bypassing the torch, while seeming to have enough pressure/flow
at the gas control.
• Cut current set too high for consumable parts being used.
• With DFC 3000 a faulty component would be expected to set a fault code in either the DPC or DMC. However, if a
wrong process is selected which doesn’t match the consumable type or if using a custom process where pressure
has been set too low or current too high that could cause 108 without setting any faults in the DFC 3000.
• A broken pilot wire in the torch lead making intermittent contact can allow piloting or sometimes the torch can transfer
using only HF (high frequency). This intermittent connection will upset the tip voltage measurement and can result in
the 108 code. Symptom is - it may cut for a short time then fault. Check for an open/broken torch lead pilot wire.
• Physically shorted torch body between anode (tip) and cathode (electrode).
The fault resulting in a 108 code is measured while cutting. It is more likely a shorted torch body, depending on the resistance
of the short, it will set code 208 (Unwanted Current) as that is measured prior to starting cut However, it must be considered
as a last resort.
109 Part Process not Configured.
This represents a status, not a fault. This is used with the DFC 3000 only. It means the operator hasn’t loaded the cutting
process from either the TSC 3000 or from the program embedded in the cutting table CNC controller. The solution is to load
a process. The code will continue to be displayed until the CNC Start is applied at which time the code will clear.
110 Not Used. This is one of the reserved codes from the earlier product.
Group 2 – Plasma Power Supply codes
General:
LEDS
Several LEDs are used as indicators on the different inverter module boards. RED LEDs indicate faults. Green LEDs should
be on for the most part. Green LEDs are: On the main board, D4-READY; On the Cap Bias Board, D6, -12V, D11 +12VP (pri-
mary referenced), D13, +12V; On the Control board D24, PWM will only be on when the inverter is enabled and its brightness
varies with the duty cycle of the PWM.
Signals:
General description of some Inverter Signals passed to the CCM that can generate fault codes in Group 2.
“Ready” also called AC IN FLT (D4, READY LED, green, on Main Inverter board)
On the inverter main board we measure the input voltage. The 3 phases are rectified and lightly filtered to achieve an average
voltage. Due to the light filtering a missing phase will also lower the average voltage so it will be detected. Voltage in the
correct range turns on the READY LED D4 (on the far left of the main boards, in the upper part of the “B” section or lower
part of the “A” section). Voltage outside the correct range or missing phase will turn D4 off.
An AC Input Fault by itself (no other faults occurring at the same time) will set codes in the 241-246 group depending on
which inverter sees the problem.