Hypertherm Command THC Instruction Manual page 172

Problem
Torch arc fails to transfer to workpiece.
Arc extinguishes immediately after transfer/excessively
large pierce hole.
Torch moves before workpiece is pierced all the
way through.
Torch dives below cutting height immediately after
pierce delay and before AVC begins.
Torch dives toward workpiece immediately after
AVC begins.
Torch retracts from workpiece immediately after
AVC begins.
Erratic voltage control.
Retract begins before arc has extinguished.
Failure to retract.
CommandTHC for X-Y Table Instruction Manual
Solution
• Check that Pierce Height is not too high by checking
Set Cut Height on Main Operating Screen and Pierce
Height Factor on Setup Screen A.
• Check work lead connection.
• Check torch consumables.
• Check for Transfer signal on control PCB, Machine
Interface Inputs, that D17 is illuminated.
• Check Pierce Delay on Automatic Operating Screen;
the delay is set too long. (The torch dwells in the
piercing position too long before machine motion.)
• Check that Machine Motion Out is active after
Pierce Delay ends.
Check on control PCB, Machine Interface Outputs, that
D25 is illuminated.
• Check Pierce Delay on Automatic Operating Screen,
the delay is set too short.
• Increase Set Cut Height on Automatic Operating
Screen and decrease Pierce Height Factor on
Setup Screen A.
• Increase Machine Accel Delay on Setup Screen A.
• Increase Set Arc Volts on Automatic Operating
Screen.
• Increase Machine Accel Delay on Setup Screen A.
• Decrease Set Cut Height on Automatic Operating
Screen.
• Decrease Set Arc Volts on Automatic Operating
Screen.
• Increase Set Cut Height on Automatic Operating
Screen.
• Check plasma interface arc voltage wiring.
• Check for faulty grounds (work lead connection.)
• Check for water leaks.
• Increase Retract Delay on Setup Screen A.
• Decrease Homing Speed on Setup Screen A.
• Check for obstructions in the torch path and
torch lead set.
OPERATION
4-17
11