Tweco 50 CutMaster - Manual (Page 25)

Manual 0-2805 4-3 OPERATION
4.03 Preparations For Operating
This procedure should be followed at the beginning of
each shift:
WARNING
Disconnect primary power at the source before as-
sembling or disassembling power supply, torch
parts, or torch and leads assemblies.
A. Torch Parts Selection
Check the torch for proper assembly and appropri-
ate front end torch parts. The torch parts (shield cup,
tip, gas distributor, and electrode) must correspond
with the type of operation (cutting or gouging). Re-
fer to the torch manual for proper parts selection.
B. Check Primary Input Power Source
1. Check the power source for proper input voltage.
Make sure the input power source meets the
power requirements for the unit per subsection
2.03-A, Specifications / Design Features.
2. Connect the input power cable (or close the main
disconnect switch) to supply power to the system.
C. Gas Selection
Select desired single gas supply. Make sure gas source
meets requirements (refer to
subsection 3.06A, Gas
Requirements). Check connections and turn gas sup-
ply on.
D. Work Cable Connection
Check for a solid work cable connection to the work-
piece.
E. Torch Connection
Check that the torch is properly connected.
F. Power On
On the Power Supply place the ON / OFF switch to
the ON position.
G. Select Current Output Level
On the Control Panel, set the desired current output
level between 20-40 amps for cutting or gouging.
H. Set Operating Pressure
Place the RUN / SET switch to the SET position. Gas
will flow. Adjust gas pressure control to 70 psi (4.8
bar).
I. Prepare to Cut
Return the RUN / SET switch to RUN position. Gas
will not flow until the Torch Trigger is pressed.
The system is now ready for operation. Activate the
torch (press torch switch on the handle, send START
signal from CNC or press the torch switch on the Re-
mote Pendant). There is a 2 second pre-flow before
the arc starts.
4.05 Sequence of Operation
The following is a typical sequence of operation for this
power supply. Refer to Appendix 2 for block diagram.
1. Close main power source disconnect switch.
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 position.
a. AC Power Indicator blinks ON and OFF
for eight seconds then stays ON. Fan turns on.
NOTE
Gas comes on if Torch Trigger is pressed (although
unit will not pilot until switch is released and re-
closed after the light stops blinking).
4. Place RUN / SET switch to SET mode.
a. Gas solenoid opens and gas flows to set pres-
sure. Gas Pressure Regulator / Filter Assem-
bly should be set to 70 psi (4.8 bar). GAS indi-
cator turns ON.
NOTE
GAS Indicator will not come ON if the gas pres-
sure is set below 35 psi (2.4 bar) at the Gas Pres-
sure Regulator / Filter Assembly.
5. Place RUN / SET switch to RUN mode.
a. Gas flow stops. GAS Indicator turns OFF.
6. Protect eyes and activate torch.
a. Gas pre-flow starts (approximately 2 seconds).
GAS Indicator turns ON.
7. After gas pre-flow:
a. Power Supply enabled. DC indicator
turns ON. Pilot Relay closes.
8. Pilot arc is established