Maintaining the PowerPact B Circuit Breaker during Operation
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HAZARD OF ELECTRIC SHOCK, EXPLOSION, OR ARC FLASH
Failure to follow these instructions will result in death or serious injury.
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Like most equipment, electrical switchboards age whether they are being used or not. Aging is mostly caused by environmental influences and operating conditions.
To help circuit breakers keep the operating and safety characteristics specified in the catalog for the whole of their service life:
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Install circuit breakers in optimum environmental and operating conditions (described in the following table).
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Make sure that maintenance operations are carried out by qualified electrical personnel.
Environmental and Operating Conditions
The following table describes optimum environmental and operating conditions.
Environmental and Operating Factors |
Optimum Conditions |
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Temperature |
Average annual temperature outside the switchboard is < 25 °C (77 °F). |
Loading |
Loading is < 80% of In for 24 hours a day. |
Harmonics |
Harmonic current per phase is < 30% of In. |
Humidity |
Relative humidity is < 70%. |
Corrosive atmosphere (SO2, NH3, H2S, Cl2, NO2) |
The circuit breaker is installed in environmental category 3C1 or 3C2 (IEC60721-3-3). |
Saline environment |
The circuit breaker is installed in an environment free of salt mist. |
Dust |
The dust level is low. If necessary, the circuit breaker is in a switchboard that is fitted with filters or is IP54 ventilated. |
Vibration |
Continuous vibration is < 0.2 g. |
Maintenance programs apply to optimum environmental and operating conditions. Outside these limits, circuit breakers are subject to accelerated aging, which can quickly lead to problems.
In harsh environmental and operating conditions, refer to the derating tables and reduce the maintenance intervals (see Enviromental Conditions).
Regular Preventive Maintenance
Maintenance recommendations are intended to maintain the equipment or subassemblies in a satisfactory operational state for their useful service life.
The following table summarizes maintenance operations and intervals for the three preventive maintenance levels:
Maintenance Interval |
Maintenance Operations |
Performed by |
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1 year |
Basic level tasks: visual inspection and functional testing, replacement of inoperative accessories. |
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2 years |
Advanced level tasks: Basic level tasks, plus operational servicing and subassembly tests. |
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3 years |
Exclusive level tasks: Advanced level tasks, plus manufacturer diagnostics and part replacements by Schneider Electric Services. |
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The maintenance intervals in the previous table are for normal environmental and operating conditions. If all environmental conditions are more favorable, maintenance intervals can be longer. For example,
Advanced level tasks could be carried out every three years.
If any one of the conditions is more severe, perform maintenance more frequently. For advice, contact Schneider Electric Services.
Functions linked specifically to safety require particular maintenance intervals.
Maintenance Operations Required
Maintenance operations mainly consist of checks and inspections A, E, F, and G, as defined for commissioning (see List of Checks and Inspections).
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HAZARD OF Injury or EQUIPMENT DAMAGE
Insulation and dielectric strength tests must only be
carried out by qualified electrical personnel.
Failure to follow these instructions can result in injury or equipment damage.
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Maintenance operation |
Year 1 |
Year 2 |
Year 3 |
Year 4 |
Year 5 |
---|---|---|---|---|---|
Insulation and dielectric strength tests (A) |
✓ |
✓ |
✓ |
✓ |
✓ |
Inspect mechanical equipment (E) |
✓ |
✓ |
✓ |
✓ |
✓ |
Measurement of insulation resistance |
— |
— |
— |
— |
✓ |
Check mechanical operation (F) |
✓ |
✓ |
✓ |
— |
✓ |
Check the closing time, opening time, and voltage release characteristics |
— |
✓ |
— |
✓ |
✓ |
Clean equipment (G) |
✓ |
✓ |
✓ |
✓ |
✓ |
For a detailed definition of the maintenance operations, contact Schneider Electric Services.