ESAB POWERCUT-1500 Manuel D'instructions page 185

SECTION 5 TROUBLESHOOTING
5.1 TROUBLESHOOTING
ELECTRIC SHOCK CAN KILL! Be sure that all primary power to the
machine has been externally disconnected. Open the line (wall)
disconnect switch or circuit breaker before attempting inspection or
work inside of the power source.
Check the problem against the symptoms in the following troubleshooting
guide. The remedy may be quite simple. If the cause cannot be quickly
located, shut off the input power, open up the unit, and perform a simple
visual inspection of all the components and wiring. Check for secure
terminal connections, loose or burned wiring or components, bulged or
leaking capacitors, or any other sign of damage or discoloration.
The cause of control malfunctions can be found by referring to the
sequence of operations and electrical schematic diagram (Figure 5-1) and
checking the various components. A volt-ohmmeter will be necessary for
some of these checks.
Voltages in plasma cutting equipment are high enough to cause
serious injury or possibly death. Be particularly careful around
equipment when the covers are removed.
NOTE
Before checking voltages in the circuit, disconnect the power from the
high frequency PC Board (PCB-2, Connector J2) to avoid damaging your
voltmeter.
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