Troubleshooting -14, Troubleshooting – Hypertherm HT4001 Plasma Arc Cutting System User Manual
Page 140

MAINTENANCE
11-96
6-14
HT4001
Instruction Manual
1. The fans are not operating
and the POWER AC indicator
does not illuminate.
1.1. Main disconnect switch is in OFF position.
Turn main disconnect switch ON.
1.2. Associated wiring not making good contact.
Check wiring from main disconnect switch to REC1 of power
distribution board.
1.3. CR2 on the power distribution board (PCB1) is defective.
Check that CR2 switches when CB1 is switched to ON. See
Figure 6-2 for location of CR2. If CR2 is defective, replace PCB1.
2. The POWER AC indicator
illuminates, but the fans are
not running.
2.1. Terminal lugs located at the fans (see Figure 7-1 for location of
fans) are not seated together securely and/or not getting 120VAC
from power distribution board.
• Check pins, connectors and associated wiring for good
continuity.
• Check for 120VAC at the terminals.
Troubleshooting
The troubleshooting section is presented by following normal operational sequence.
Before troubleshooting for specific problems, be sure that unit passes Initial Checks as outlined earlier in this
section.
Problem
Possible Causes and Solutions
Move circuit
breaker CB1 to ON
position
WARNING
SHOCK HAZARD: Always use caution when servicing a power supply when the covers are removed.
Dangerous voltages exist within the power supply which could cause injury or death. If questions or
problems arise during servicing, call the Hypertherm Technical Services Department at 1-800-647-9878.