ESAB 0558001729, Installation, Operation And Maintenance Manual

Page: 49 / 120

SECTION 6 Troubleshooting
ESP 400C and 600C Plasma Power Sources
6-11
Problem Possible Cause Action
Works OK at 250A or less- Over
current – Faulty Right Side Loose or unplugged connector at
Right PWM/Drive PCB (PCB3)
Faulty Right PWM/Drive PCB
Check voltage between P5-1 and
P5-2 at the right PWM/Drive PCB
(PCB3). Should be 20V AC.
Between P5-1 and P5-3 should
be 40V AC. If not the control
transformer (T7) is faulty.
Secure connector
Replace right PWM/Drive PCB
P/N 38030
Replace control transformer T7
Power Supply turns off
prematurely in the middle of the
cut.
“Contactor On” signal is removed
from unit.
Momentary loss of primary input
power.
Faulty condition, indicated by
illumination of the fault lamp.
Faulty condition, indicated by the
illumination of the power reset
fault lamp.
Current setting too low.
Remote current signal removed
during cut.
Power source is OK. Trouble
shoot process controller.
Restore and maintain input
voltage within ±10% of nominal.
Remove control PCB (PCB1)
access panel to determine the
fault causing the shutdown.
Refer to fault light illumination
section.
Remove control PCB (PCB1)
access panel to determine the
fault causing the shutdown.
Refer to fault light illumination
section.
Increase current setting
Fix remote current signal