Control board led definitions, Troubleshooting & repair, Trigger circuit test (continued) – Lincoln Electric PRO-CUT 55 SVM140-A User Manual
Page 79
CONTROL BOARD LED DEFINITIONS
LED1: (Red) This light indicates that 18 VAC is
being supplied to the control board from the
auxiliary transformer. It also shows that the 18
VAC is being rectified and should be regulated to
+15 VDC. This +15 VDC supply is used to power
the circuitry on the control board.
LED2: (Red) This light indicates that the +5.5
VDC is present. This voltage is derived from the
+15 VDC supply. The +5.5 VDC supply is used
to power the circuitry on the control board.
LED3: (Red) This light indicates that 18 VAC is
being supplied to the control board from the
auxiliary transformer. It also shows that the 18
VAC is being rectified and should be regulated to
-15 VDC. This -15 VDC supply is used to power
the circuitry on the control board.
TROUBLESHOOTING & REPAIR
F-42
F-42
PRO-CUT 55
TRIGGER CIRCUIT TEST (continued)
PRO-CUT 55 CONTROL G3328
LED2
LED1
LED3
FIGURE F.11 - CONTROL BOARD LEDs