Firepower FP-18 Service Manual page 14

Locate your symptom, check causes (easiest is usually
first; sometimes the order is important, if noted), then
remedies. Repair as needed being sure to verify that the
unit is fully operational after any repairs.
C. No Power, AC switch on, red indicator
dark, no fan.
1. No power from wall unit.
a. Test electrical outlet with voltmeter or some
other known good load (trouble light, hand
drill, etc).
If AC line voltage is present, go to step #C2.
If AC line voltage is not present, replace fuse
or reset circuit breaker.
2. Damaged power cord.
a. Confirm with voltmeter if ac line voltage is
present at input to power switch.
If ac voltage is present, proceed to subsection
C3.
If ac line voltage is not present, replace power
cord.
3. Power switch faulty.
a. Confirm with voltmeter if AC line voltage is
present at main capacitor terminals when
power switch is on.
If ac line voltage is not present, replace power
switch.
D. Power OK, service circuit breaker or
fuse opens after the power switch is
switched on.
NOTE
Proceed with troubleshooting for these components
in order:
1. Faulty Fan.
a. Disconnect the Fan and insulate the two wires
going to the Fan with tape (separately), then
reapply power.
If the circuit breaker or fuse opens after the
power switch is switched on, go to step #D2.
If the circuit breaker or fuse is okay, replace
Fan.
Firepower FP-18 Plasma Cutter
2. Faulty Transformer Assembly or Capacitor.
a. With the Fan still disconnected, disconnect two
leads from the transformer that are connected
to the Capacitor , then apply power.
If the circuit breaker or fuse opens after power
is applied, the Capacitor is shorted. Replace
Capacitor.
If the circuit brreaker or fuse is okay, replace
Transformer.
E. Power OK, fan runs, no compressor
operation or pilot when torch switch
pressed.
1. Shield cup loose, PIP not making contact.
a. Reseat the torch parts, tighten shield cup.
2. Unit overtemp.
a. Leave power on so fan can cool unit, test again
after 10 min.
3. Shorted torch parts.
a. Replace torch consumables.
4. Torch switch may have broken or shorted wires.
a. Refer to subsection 3.6, Torch and Leads Trouble-
shooting.
5. Overheated or faulty Compressor.
a. Press the torch switch. If a clicking can be heard
and/or the Relay is actuating (test button on
side pulls in), the Compressor motor may have
failed or overheated. If the Case of the Com-
pressor motor feels very warm, allow it to cool
and try again. The Compressor has its own
overtemp cutout switch.
If the unit fails to operate once it has cooled
down, replace the compressor.
6. Shorted Bridge Rectifier (BR2)
a. If the Rectifier (upper) is hot and the Trans-
former is buzzing or heating up, the rectifier is
shorted. Replace Rectifier.
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