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ROUTINE MAINTENANCE
1.Perform the following preventive maintenance procedures at least once every six months. It is good practice to keep a preventive maintenance record; a record tag attached to the machine works best.
2.Remove the machine
3.Keeping the machine clean will result in cooler operation and higher reliability. Be sure to clean the following areas with a low pressure air stream. See figure D.2 for component locations.
•Power and control printed circuit boards
•Power switch
•Main transformer
•Input rectifier
•Heat sink fins
•Input Filter Capacitors
•Output Terminals
4.Examine capacitors for leakage or oozing. Replace if needed.
5.Examine the sheet metal case for dents or break- age. Repair the case as required. Keep the case in good condition to ensure that high voltage parts are protected and correct spacings are maintained. All external sheet metal screws must be in place to assure case strength and electrical ground continuity.
6.Check electrical ground continuity. Using an ohm- meter, measure resistance between either output terminal and an unpainted surface of the machine case. (See Figure D.2 for locations.) Meter reading should be 500,000 ohms or more. If meter reading is less than 500,000 ohms, check for electrical components that are not properly insulated from the case. Correct insulation if needed.
7.Replace machine cover and screws.
FILTER CAPACITOR CONDITIONING
A protection circuit is included to monitor the voltage across filter capacitors C1 and C2. In the event that the capacitor voltage is too high, the protection circuit will prevent output. Nominal trip setting is at 230/460 VAC +15%. Reset occurs about 3% lower (230/460 VAC +12%).
On new installations, the protection circuit may also prevent output providing all these circumstances are met:
1.Machine is connected for
2.Machine did not have power applied for many months.
3.Machine will not produce output when power is first switched on.
If these circumstances apply, the proper action is to switch the machine on and let it idle for up to 30 min- utes. This is required to condition the filter capacitors after an extended storage time. The protection circuit will automatically reset once the capacitor conditioning and resultant voltage levels are acceptable. It may be necessary to turn the power switch off and back on again after this period.