Tweco 1000 Merlin(Sept1999) - Manual (Page 32)

OPERATION 28 Manual 0-2731
5. Primary Input Power Filter, Cable and Strain Relief
The Input Filter Assembly is mounted to the rear panel
of the power supply. A strain relief is supplied to se-
cure the shielded primary input AC power cable to
the Input Filter Assembly. The input cable is routed
through the strain relief and is connected to input ter-
minals of an input filter.
6. Two Stage Air Line Filter
The Two Stage Air Line Filter will remove moisture
and contaminants from the air stream when using
compressed air. The filter is capable of filtering to at
least 5 microns.
7. Coolant Filter Assembly
The Coolant Filter Assembly mounted to the rear panel
is used to filter the coolant as it returns to the reser-
voir. The filter is a screen type which is easily cleaned
or replaced.
4.04 Sequence of Operation
The following is a typical sequence of operation for the
cutting system. Refer to Appendix II for a block diagram.
1. Close main power source disconnect.
a. AC power is available at the Power Supply.
2. Place RUN/SET switch to RUN mode.
3. Place the ON/OFF power switch on the front panel
of the Power Supply to ON.
a. Fan turns on.
b. Coolant Pump turns on.
c. AC Power indicator blinks ON and OFF for
eight seconds then stays ON. During this eight
seconds there is a start-up purge of gas through
the system (see NOTE).
NOTE
Gas will flow only if gas supply is connected, turned
on and gas regulator is not set to zero.
4. Place RUN/SET switch to SET mode.
a. Gas solenoid opens and gas flows to set pres-
sure.
b. GAS indicator turns ON.
NOTE
GAS indicator will not come ON if the gas pres-
sure is set below 30 psi (2 bar or 207 kPa) at the
Plasma Gas Regulator or if coolant flow switch is
not satisfied.
5. Place RUN/SET switch to RUN mode.
a. Gas flow stops.
b. GAS indicator turns OFF.
6. Protect eyes and press or activate torch switch
a. Gas pre-flows starts.
b. GAS indicator turns ON.
7. After gas pre-flow (approximately 2 seconds)
a. Power supply enabled.
b. DC indicator turns ON.
c. Pilot relay closes.
8. Pilot arc is established
9. Move Torch within transfer distance of workpiece.
a. Main arc transfer.
b. Pilot arc OFF.
10. Complete cutting operation.
NOTE
If the torch is lifted from the workpiece, while still
having the torch activated, the main arc will stop
and the pilot arc will automatically restart.
11. Release or deactivate the torch switch.
a. Main arc stops.
b. Pilot arc stops (power supply enable signal re-
moved).
NOTE
If torch is activated during post-flow, pilot arc will
immediately restart.
If torch is within transfer distance of workpiece,
main arc will transfer.
12. Gas will flow for 20 seconds (post-flow).
a. Gas solenoid closes.
b. Gas flow stops.
c. GAS indicator turns OFF.
13. Place the ON/OFF power switch on the front panel
of the unit to OFF
a. AC Power indicator turns OFF.
b. Fans turn OFF.
14. Place the main power disconnect to open.
a. Main AC power is removed from the system.