Hobart GPU-600 Series, Operation And Maintenance Manual

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OM-2244 / Operation and Maintenance Manual
DCS-600/ Series 500082 / Solid State Transformer-Rectifiers
December 15, 2014 Chapter 2-1
Page 9
Trouble, Symptom, Condition Probable Cause Test, Check, and/or Remedy
Output Voltage Not Proper Level
1. Poor voltage regulation a. Loose connection of voltage
sensing lead Check connection at output
contactor and control circuit board.
Tighten connection as necessary.
2. Output voltage too high (above
32 Volts) a. Voltage calibration off Attempt calibration per Section 2-2. If
calibration isn’t possible replace PC
control board.
b. Voltage sensing lead open Repair or replace voltage-sensing
lead.
3. Unstable voltage a. Open filter capacitor Find and replace defective capacitor.
b. One or more SCRs not firing
properly Adjust balance control or replace
defective SCR heat sink assembly if
oscilloscope shows faulty SCR
devices. Replace PC control boards
if oscilloscope shows no gate pulse
and the PC control board inputs and
controls are proper except for output.
Trouble, Symptom, Condition Probable Cause Test, Check, and/or Remedy
Output Contactor Fault
1. Output contactor will not close. a. Defective output switch (S2) With the unit turned off, place a
jumper between terminals 2 and 4 on
S2. Turn S1 on. If output contactor
closes, S2 is defective. Replace.
b. Defective input contactor
auxiliary contacts (K1) With the unit turned off, place a
jumper between terminals NO 1 and
COM 3 on input contactor. Turn S1
on, and place S2 in Close position.
If output contactor closes, K1 is
defective. Replace.
c. Defective output voltage select
switch (S103) (if applicable) With the unit turned off, place a
jumper between terminals 4 and 5 on
S103. Turn S1 on, and place S2 in
Close position. If Output contactor
closes, S103 is defective. Replace.