ESAB Plasmarc EPP-450, Manual

Page: 47 / 68

47
section 6 troubleshootinG
problem possible cause action
Power Supply turns off prema -
turely in the middle of the cut.
“Contactor On” signal is removed from unit. Power source is OK. Trouble shoot pro
-
cess controller.
Momentary loss of primary input power.
Restore and maintain input voltage
within ±10% of nominal.
Faulty condition, indicated by illumination
of the fault lamp.
Remove control PCB (PCB1) access panel
to determine the fault causing the shut -
down. Refer to fault light illumination
section.
Faulty condition, indicated by the illumination
of the power reset fault lamp.
Remove control PCB (PCB1) access panel
to determine the fault causing the shut -
down. Refer to fault light illumination
section.
Current setting too low. Increase current setting
Remote current signal removed during cut. Fix remote current signal
problem possible cause action
Output current is unstable and
drifts above or below the set -
ting.
Place the PANEL / REMOTE switch in the “PANEL”
position. Adjust current control pot. If current
no longer drifts, the remote current control
signal is faulty.
Fix the remote current control signal to
operate the PANEL / REMOTE switch in
the “PANEL” position.
Select “PANEL” on the PANEL / REMOTE switch
and adjust the current control pot. The cur -
rent still drifts, measure the current reference
signal at TB1-4 (+) and TB1-5 (-). If the signal
drifts, the current control pot is faulty. If the
signal does not drift, the Control PCB (PCB1)
is faulty.
Replace the current control pot.
Replace the control PCB (PCB1) P/N
0558038312