Hypertherm Powermax30 XP Service Manual - Manual (Page 81)

Powermax30 XP Service Manual 808150 Revision 1 81
5 – Troubleshooting and System Tests
Test 5 – torch stuck open or torch stuck closed
If the nozzle and electrode are not in contact before the torch trigger is pressed, the power supply detects a “torch stuck
open” fault. If the nozzle and electrode are in contact after the torch trigger is pressed, the power supply detects a “torch
stuck closed” fault.
Use the following test to determine if the torch is stuck in either position.
1. Set the power switch to OFF (O), disconnect the power cord from the power source, and disconnect the gas supply.
2. Remove the power supply handle and cover. (See Remove the power supply cover on page 88.)
3. Remove the component barrier. (See Remove the component barrier on page 90.)
4. Measure the resistance from the torch lead’s white wire group and red wire. The resistance should read very low, a
closed circuit.
Figure 20
5. Turn ON (I) the power and measure the resistance between the same points. The resistance should read very high,
an open circuit.
6. If the resistance reads as open, the nozzle and electrode are not in contact, or one of the wires in the lead is broken.
7. If the resistance reads as closed, the nozzle and electrode are in contact or one of the wires in the torch lead is
broken. Make sure that the torch plunger moves freely in the torch head.
CAUTION!
To avoid causing a short or damage to the multimeter, do not fire the torch with the multimeter
connected to the power board.
White wire group
Red wire