ESAB EPP-400 - Page 39

39
Problem Possible Cause Action
Fault light illuminates at the end of
cut but goes o at the start of the
next.
Normal condition caused when ter-
minating the arc by running the torch
o the work or the arc being attached
to a part that falls away.
Reprogram cutting process to
ensure arc is terminated only by
removing the “Contactor On” signal.
LED 3 – (amber) Bus Ripple
Imbalance of 3-phase input power
Maintain phase voltage imbalance
of less than 5%.
Momentary loss of one phase of
input power
Restore and maintain input power
within ±10% nominal
Faulty control PCB1 Replace PCB1 P/N 0558038287
LED 4 – (amber) High Bus
One or more phases of input voltage
exceed nominal line voltage by more
than 15%.
Restore and maintain line voltage
within ±10%
Faulty control PCB1 Replace PCB1 P/N 0558038287
One or more shorted diode rectiers
(D25-D28) on the “Electrode Plate”
Replace shorted diode rectiers
LED 5 – (amber) Low Bus
One or more phases of input volt-
age are lower than nominal by more
than 15%.
Restore and maintain within
±10% of nominal
Blown F1 and F2 fuses
See F1 and F2 in Blown
Fuses Section
Over temp Light comes on. See over temp in Fault Light Section
Imbalanced 3-phase input
power
Maintain phase voltage imbalance
of less than 5%
Momentary loss of one phase of
input power
Restore and maintain within
±10% of nominal
Faulty Main Contactor (K1) Replace K1
FAULTY Control PCB1 Replace PCB1 P/N 0558038287
SECTION 6 TROUBLESHOOTING
6.3.3 Fault Light Illumination