Tweco PC-500 - Manual (Page 49)

Manual 0-4601 A-1 APPENDIX
APPENDIX 1: SEQUENCE OF OPERATION
(BLOCK DIAGRAM)
ACTION:
ON / OFF switch to ON
RESULT:
AC indicator ON.
Fan(s) ON.
GAS indicator ON
when input
pressure is adequate
for power supply operation.
Power circuit ready.
ACTION:
Protect eyes and activate torch.
RESULT:
Gas flows briefly, then stops.
Gas restarts.
DC indicator ON
Pilot arc established.
Art #A-03706A
ACTION:
Unplug input
power cord or
open external
disconnect.
RESULT:
No power to system.
ACTION:
Connect work cable to workpiece.
Set output amperage.
RESULT:
System is ready
for operation.
ACTION:
RUN /
Rapid Auto Restart /
SET switch
to SET
RESULT:
Gas flows to set pressure.
ACTION:
RUN /
Rapid Auto Restart / SET
switch to RUN
(for most applications)
or to
Rapid Auto Restart
(for gouging, trimming,
or expanded metal
applications)
RESULT:
Gas flow stops.
ACTION:
Release torch trigger.
RESULT:
Main arc stops.
Gas flow stops after post - flow.
ACTION:
ON / OFF switch
to OFF
RESULT:
All indicators off.
Power supply fan(s) shuts off.
ACTION:
Close external
disconnect switch.
RESULT:
Power to system.
ACTION:
Torch moved within
transfer distance of workpiece.
RESULT:
Main arc transfers.
Pilot arc off.
PILOT ARC
ACTION:
Torch moved away from work (while
still activated).
RESULT:
Main arc stops.
Pilot arc automatically
restarts.