19
SECTION 5
TROUBLESHOOTING
The cause of control malfunctions can be
found by referring to the sequence of opera-
tions 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 equip-
ment when the covers are removed.
NOTE
Before checking voltages in the circuit, disconnect
the power from the high frequency generator to
avoid damaging your voltmeter.
5.1 TROUBLESHOOTING
ELECTRIC SHOCK CAN KILL! Be sure that all
primary power to the machine has been exter-
nally disconnected. Open the line (wall) discon-
nect 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.
Depress torch switch. After 2 seconds, is high frequency present?
No
Repair/replace
high frequency
unit
Repair/replace
power source
Yes
5.2 TROUBLESHOOTING GUIDE
A.
Difficult Starting.
• Change electrode
• Change nozzle
• Check for good, clean connection of work lead to workpiece
• Check air pressure 55 -65 psi (4 - 5 bar)
• Check torch power cable for continuity
Is the "Air" LED light on
Repair/replace
control PCB
Yes
No
