Supply Fuses Blown

Input transformer tapped incorrectly. 

Check transformer tap connection according to incoming supply voltage.

Defective transformer.

Replace transformer.

Defective Varistor

Replace QVR1, QVR2, or QVR3

Circuit Breaker trips when turned on.

Control transformer tapped incorrectly.

Check transformer tap setting.

Defective control transformer

Replace transformer.

Circuit Breaker trips when start/stop switch is energized.

Shorted DC buss

With power removed, ohm check across wires 9 and 16.  Should read 20 K-ohms in one direction, and 50 to100 ohms in the opposite direction.  If not correct, proceed to next step.

Shorted rectifier. (Rect. 1)

Check rectifier with VOM.  Replace rectifier if shorted.  Otherwise proceed to next step.

Inverter fault

Make sure that the output power control is turned fully counter-clockwise.  Proceed to next step. 

Defective Circuit Board

Disconnect the ribbon cable connector from the control board socket. If circuit breaker stays energized, replace control board.  If circuit board trips, proceed to next step.

Shorted Filter Capacitor (C1)

Replace defective capacitor.

Defective SCR1

Ohm check SCR.  Replace if defective.

Feedback transformer is shorted. (T2)

Replace transformer.

Start/Stop button is pulled but nothing happens.

Interlock circuit open.

Check to be sure that the interlock circuit is connected from the treater station to the power supply.  Place temporary jumper on interlock terminals and try to energize start button.  If okay, remove jumper and locate defective interlock.

Loose wire or connection.

With power off, lightly tug on interlock wiring at power supply and treater station.  Ensure a good connection.

No Control Voltage

Check for blown control transformer fuse.

Circuit Breaker trips when start/stop switch is energized and output adjust is turned clockwise

Short circuit at treater station.

Disconnect power.  Disconnect high voltage secondary lead from transformer.  If unit runs, check for short circuit in output cable, or treater station.  If unit still trips, proceed to next step.

Defective High Voltage transformer.

Replace High Voltage transformer. 

WARNING:  Do not operate power supply with transformer disconnected or feedback transformer (T2) will overheat.

Incorrect tap setting on high voltage transformer.

Change tap to X4 and try again. 

Output power adjust is turned clockwise, but nothing happens.

Defective Control Board

Replace control board and restart power supply.

No meter reading with unit operating.

Defective panel meter.

If power supply can be heard, check for good connections to meter.  If okay replace meter.

Frequency Limit

Power supply is operating at maximum safe output frequency. 

If unable to achieve full power, change high voltage transformer tap and check again.  Check for proper electrode gap and alignment.

Voltage Limit

Power supply is operating at maximum safe output voltage.

If unable to achieve full power, change high voltage transformer tap and check again.  Check for proper electrode gap, and alignment.