6-5. Troubleshooting Power Source
Is input power connected to correct line voltage?
Yes
Is Power switch in the On position?
Yes
No
No
Connect unit to proper input 
voltage. (see Section
Place Power switch in the 
On position. (see Section
Is compressor | No |
operating? |
|
Yes
Does pilot arc | No |
ignite? |
|
Yes
*
Press torch trigger and listen for compressor operation. Check for Postflow air at torch. Check
Control board PC1, compressor filter, and compressor connections to PC1 and torch.
Press torch trigger and check if pilot arc ignites. Check torch consumables. *Check torch connections, relay CR1, compressor, and torch.
Is the cooling fan running?
Yes
No
*
Check Power switch S1, 
relay CR2, and thermistor
R1.
Does pilot arc
transfer to workpiece?
Yes
Place torch near workpiece and check if pilot arc “jumps” No or transfers to workpiece.
Check work clamp connec- tion. *Check Control board PC1 and connections, and torch and its connections.
Is Power light On?
Yes
Is Trouble light On?
No
No
Yes
*
Reset Power switch S1 and 
verify line power voltage.
Check relay CR2, thermistor R1, and Control board PC1.
Check torch consumables. Reset Power switch S1. If unit is overheated, wait while fan cools down unit temperature.
Check all connections, Check main transformer T1, Check inductor L1. Return to beginning of chart.
*Servicing procedure to be performed only by authorized Service Station.