Service manual

S0740 800 179/E071123/P64
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ct33f1
Code Description, power source
4 5 V power supply too low
The unregulated power supply voltage (+24 V) is too low: the smoothing capacitors cannot
keep the voltage up enough for the processor to continue to operate. The processor stops all
normal activities, expecting to be shut down.
Action: Turn off the mains power supply to reset the unit. If the fault persists, check the
power supply to circuit board 20AP1.
6 High temperature
The temperature monitoring circuit has operated. The power source is stopped, and cannot
be restarted until the circuit has reset. See also page 31.
Possible causes: Overloading, fan not working properly, cooling air inlets or outlets blocked
or obstructed or dirt on the heat exchanger.
12 Communication error (warning)
The load on the system CAN bus is temporarily too high, or there is electric noise on the
bus.
Action: Check the equipment to ensure that only one remote control unit is connected. See
also section 20AP1:2 ’The CAN bus’ on pages 29 to 30.
15 Lost messages
The bus CAN controller indicates that a message has been lost. No functions are disabled
by this fault.
Action: Check that all units are correct connected to the CAN bus. See also section
20AP1:2 ’The CAN bus’ on pages 29 to 30.
16 High open--circuit voltage (VRD)
The open--circuit voltage has been too high.
Action: Turn off the mains power supply to reset the unit. If the fault persists, check the arc
voltage feedback: see page 32.
20 High inductance in the welding circuit
The power source cannot produce the desired current because the measured inductance in
the welding circuit is too high. The fault indication is reset if the inductance reading receives
a sufficiently low value at weld start. Resetting can also be achieved by turning off the power .
Action: Use shorter welding cables and ensure that the cables are not coiled up. Place the
welding cable and connector cable next to each other. If possible, the inductance can be
reduced by welding with a shorter arc.
22 Transmitter buffer overflow
The control board is unable to transmit information to the other units at a sufficiently high
speed.
Action: A break in the bus line can cause this fault. Check the CAN cabling. Turn off the
mains power supply to reset the unit.
23 Receiver buffer overflow
The control board is unable to process information from the other units at a sufficiently high
speed. This fault is caused by abnormal loading of the microprocessor .
Action: Turn off the mains power supply to reset the unit.