CARBONE PowerMaster256, Operator'S Manual

B-6                                OPERATION                                      B-6

4-Step Sequence   

With the 4-step Selected, the following welding 
sequence will occur.   
1. Press and hold the Arc Start Switch to start the 
sequence.  
The machine will open the gas valve to start the 
flow of the shielding gas. After a 0.5 second preflow 
time, to purge air from the torch hose, the output of 
the machine is turned ON. At this time the arc is 
started.  
After the arc is started the output current will be at 
the Start current. This condition can be maintained 
as long or as short as necessary.   
If the Start current is not necessary, do not hold the 
TIG torch trigger as described at the beginning of 
this step. Instead, quickly press and release the 
trigger. In this condition, the machine will 
automatically pass from Step 1 to Step 2 when the 
arc is started.   
2. Release the TIG torch trigger to start the main 
part of the weld.   
The output current will be increased from the start 
current to the welding current. Both the start current 
and increase, or upslope time are presettable. The 
default start current is 15 amps and the default 
upslope time is 0.2 seconds.   
3. Press and hold the TIG torch trigger when the 
main part of the weld is complete.   
The machine will now decrease the output current 
at a controlled rate, or down slope time, until the 
Finish current is reached. Both the Down slope 
Time and the Finish Current are presettable. This 
Finish current can be maintained as long or as short 
as necessary. 
4. Release the TIG torch trigger.   
The output current of the machine will turn OFF and 
the gas valve will remain open to continue the flow 
of the shielding gas. The duration of this postflow 
time is adjusted by the Postflow parameter. This 
operation is shown in (4 step diagram 1).     

4 STEP DIAGRAM 1   

Possible variations of this standard sequence are 
shown below. By releasing and re-pressing the TIG 
torch trigger during the downslope step, the output 
will immediately drop to and hold at the Finish 
Current. Releasing the trigger will turn off the output 
and begin postflow. This operation shown in 

  (4 step diagram 2) 

 
 
 
 
` 
 
 
27. 220v  receptacle      

This connection supplies power to the water cooler.   
This is a 220 VAC outlet.  Do not use this 
connection to power any other device.    4 amp max. 

28. PreFlow      

Sets the TIG mode shielding gas pre flow time over 
the range of about 0 to 10 seconds before the arc 
will shut on.   

29. Start Amps &30. End Amps

Serves as the 2T/4T  beginning  and final amp 
value while using the torch switch. Allows the arc to 
be started and ended at a different amp value than 
normal welding while using the torch switch. 

31. Pulse On/Off.      

Press the touch-pad button to select the desired 
pulse mode. 

32. warning indicating light      

output current is too high or the machine    fails. 

34.Pilotarc  Connector 

Loosen the black thumb screw to connect the pilot 
arc wire to the plasma cutting  torch.  The 
thumbscrew is only used with the plasma torch. 
 
 
 
 
 
 
 
 

TORCH 
BUTTON

OUTPUT 
CURRENT 

GAS

PRE-FLOW

GAS ON

POST-FLOW