ESAB EPP-400 - Page 42

42
SECTION 6 TROUBLESHOOTING
Problem Possible Cause Action
LED 12 – (red) Left –12V Missing
Loose or unplugged P1 connector at
the left PWM / Drive PCB
Secure P1 connector
Loose or unplugged P10 connector
at PCB1
Secure P10 connector
Faulty left PWM / Drive PCB
Replace left PWM / Drive PCB P/N
0558038308
LED 12 – (red) Right –12V Missing
Loose or unplugged P1 connector at
the right PWM / Drive PCB
Secure P1 connector
Loose or unplugged P11 connector
at PCB1
Secure P11 connector
Faulty right PWM / Drive PCB
Replace right PWM / Drive PCB P/N
0558038308
Very high Output current accompa-
nied by either a left or right over cur-
rent (LED 9 or LED 6 respectively)
Shorted IGBT Replace the IGBTs
Current pot set too high Lower the current setting
Faulty left PWM / Drive PCB
Replace left PWM / Drive PCB P/N
0558038308
High remote current signal Decrease remote current signal
Faulty PCB1 Replace PCB1 P/N 0558038287
Over Temp Lamp illuminates
One or more fans inoperable Repair or replace fan(s)
Broken wire or unplugged connector
at thermal switch.
Repair broken wires and unplugged con-
nector
Obstruction to air ow closer than 3 feet
(1 m) to rear of power source.
Allow 3 ft. (1 m) minimum between the rear
of the power source and any object that may
restrict air ow.
Excessive dirt restricting cooling air
ow
Clean out excessive dirt, especially in the
extrusions for the IGBTs and freewheeling
diodes, the POS, NEG and Electrode Plates,
the main transformer (T1) and the lter
inductors (L1 and L2).
Obstructed air intake
Check and clear any obstructions from the
bottom, front, and top rear of the Power
Source.