Tweco PC-500 - Manual (Page 38)

SERVICE 5-6 Manual 0-4601
6. Unit internal fuse blown or loose
a. If blown, double-check input voltage and replace fuse per Section 5.04-C. If fuse blows again, return unit to
an authorized service center.
7. Actual input voltage does not correspond to voltage of unit
a. Verify that the input line voltage is correct. Refer to Section 2, Input Wiring Requirements.
8 . Faulty components in unit
a. Return for repair or have qualified technician repair per Service Manual.
B. Gas flows continuously when power is turned on, AC indicator flashes
1. Torch switch is activated (closed) before user turns power on.
a. Release torch switch.
2. Faulty torch switch
a. Check torch switch for continuity. Replace if necessary.
C. Gas flows continuously; Torch will not pilot when torch switch is activated; AC indicator ON
1. System is in SET mode
a. Change RUN / Rapid Auto Restart / SET switch to Rapid Auto Restart (center) or RUN (up) position.
D. No gas flow; RUN / Rapid Auto Restart / SET switch in SET position; Fans operate; AC indicator ON;
GAS indicator OFF
1. Gas not connected
a. Check gas connections.
2. Gas pressure too low for power supply operation
a. Adjust gas pressure per gas pressure label on power supply.
3. Faulty components in unit
a. Return for repair or have qualified technician repair.
E. Torch will not pilot; gas flows; AC indicator ON, GAS , TEMP , and DC indicators OFF
1. Gas pressure is below power supply minimum requirement.
a. Adjust pressure to 75 psi / 5.2 bar.
F. Torch will not pilot; gas flows; AC and Gas indicators ON; DC and TEMP indicators OFF
1. Gas pressure is below torch minimum requirement (Minimum pressure for power supply operation is lower than mini-
mum required for torch operation.)
a. Adjust pressure to 75 psi / 5.2 bar.