MAINTENANCE
1
powermax1000
Service Manual
3-25
Test 7 – torch stuck open (TSO)
• Check the resistance between the pilot arc IGBT (Q8) and J17. The value should be less than (<) 100
Ω
.
• Switch to Gas Test mode and check the resistance again. The value should be greater than (>) 1k
Ω
.
• If the value is less than (<) 100
Ω
all the time, check resistance between pilot arc IGBT (Q8) and J17 with
the torch removed. If the value is less than (< )100K
Ω
, replace the pilot arc IGBT (Q8).
• If the resistance is always greater than (>) 100
Ω
, then the electrode/nozzle circuit is open.
• Check the wiring to the torch.
• Replace all consumables and verify that the torch will fire.
Note: The retaining cap should be snug and not over-tightened.
• If the torch plunger does not move freely in the torch head, replace the torch head.
• Check to see if the pilot arc IGBT (Q8) is open by putting a jumper wire from J14 to the Pilot Arc IGBT (Q8).
Then attempt to fire the torch. If the torch fires, replace the Pilot Arc IGBT (Q8).
Note:
All values are ±25%.
Pilot arc IGBT
Q8
J17
J14
