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SAFETY PRECAUTIONS
WARNING
ELECTRIC SHOCK can kill.
•Do not touch electrically live parts or electrode with skin or wet clothing.
•Insulate yourself from work and ground
•Always wear dry insulating gloves.
EXPLODING PARTS can cause injury.
• Failed parts can explode or cause other parts to explode when power is applied.
•Always wear a face shield and long sleeves when servicing.
See additional warning information throughout this operator’s
CAPACITOR DISCHARGE PROCEDURE
1.Obtain a power resistor (25 ohms, 25 watts).
2.Hold resistor body with electrically insulated glove. DO NOT TOUCH TERMINALS. Connect the resis- tor terminals across the two studs in the position shown. Hold in each position for 1 second. Repeat for all four capacitors.
RESISTOR
CAPACITOR
TERMINALS
3.Use a DC voltmeter to check that voltage is not present across the terminals on all four capacitors.
VISUAL INSPECTION
Clean interior of machine with a low pressure air stream. Make a thorough inspection of all compo- nents. Look for signs of overheating, broken leads or other obvious problems. Many problems can be uncovered with a good visual inspection.
ROUTINE MAINTENANCE
1.Every 6 months or so the machine should be cleaned with a low pressure airstream. Keeping the machine clean will result in cooler operation and higher reliability. Be sure to clean these areas:
•All printed circuit boards
•Power switch
•Main transformer
•Input rectifier
•Auxiliary Transformer
•Reconnect Switch Area
2.Examine the sheet metal case for dents or breakage. Repair the case as required. Keep the case in good con- dition to insure that high voltage parts are protected and correct spacings are maintained. All external sheet metal screws must be in place to insure case strength and electrical ground continuity.
PERIODIC MAINTENANCE
Overload Protection
The machine is electrically protected from producing high output currents. Should the output current exceed 430A, an electronic protection circuit will reduce the current to approximately 100A. The machine will continue to produce this low current until the protection circuit is reset. Reset occurs when the output load is removed.
Thermal Protection
Thermostats protect the machine from excessive operating temperatures. Excessive temperatures may be caused by a lack of cooling air or operating the machine beyond the duty cycle and output rating. If excessive operating temperature should occur, the thermostat will prevent output voltage or current. The meter will remain energized during this time.
Thermostats are