Fault Finding - NewArc RT2500 Operational Manual

4. Fault finding

Machine operation
Most problems with the operation of the RT2500 can be overcome by following the procedures below.
No digital display on switch on
Check that the machine is attached to a working mains supply, that it is correctly plugged in and
any isolator switches are turned on. Have a competent electrician check that there are no fuses or
overload devices interrupted, that the mains plug is fitted correctly and that there are no loose wires or
connections, check that there are no breaks in the mains cable. If all the above appear satisfactory have a
competent maintenance engineer check the fuses inside the machine.
Digital display lit but no output on MMA.
Make sure the mode switch is in the MMA position. Ensure that the overload indicator goes off after
15 seconds. If all the above appear satisfactory, have a competent maintenance engineer check the
fuses inside the machine. The relevant one is on the Main control PCB. This PCB is located at the top right
hand side of the machine. The fuse is located on the top of the PCB halfway along its length.
Output on MMA but not on TIG.
Check to see if gas flows when the torch switch is pressed, if not, check that the torch switch lead is in
good condition, that there are no breaks in the cable and the wires in the plug and torch switch are still
securely attached. Check that the torch switch plug is connected properly. If gas flow is present, check
the machine works in 'lift TIG' mode to determine whether the problem is in the TIG welding mode or
that just the HF is not working.
No HF operation.
Have a competent maintenance engineer check the fuse on the HF PCB. This PCB is located in
the 'U' channel on the top of the machine. The fuse is located near the top of the PCB toward the
front of the machine.
Thermal cut-out indicator lit
This indicator must be off for normal operation. If on it indicates that the RT2500 has overheated and
the power stages of the RT2500 have been shut down so you will get no current output.
In normal climate conditions (below 25°C) the RT2500 has a 100% duty cycle, so operation of the
thermal cut out indicates that the inside of the machine is likely choked with dust and therefore not
being cooled properly. In Hot climates (above 25°C) It indicates that you are exceeding the duty cycle of
the RT2500, leave switched on for a few minutes and the RT2000 will return to normal operation. In this
circumstance, do not switch the RT2000 off as this will stop the operation of the cooling fan and greatly
extend the cool down period. Frequent tripping of the thermal cut-out, especially at low current settings
is indicative that the inside of the machine is probably choked with dust.
Any operating problems not covered above means the RT2500 must be checked by a
trained Newarc service engineer or returned to the factory for repair.
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RT2500