ELECTRICAL PREVENTIVE MAINTENANCE (EPM) PROGRAM

Recommended Maintenance Practices for Electrical Distribution System Equipment

Electrical equipment failures account for hundreds of Ringgits in damage and lost business every year. As an electrical installation continues to age, measures must be taken to prevent failure or short circuit from the installation. Ironically, more than two-thirds of electrical system failures can be prevented by a routine preventive maintenance program. The failure rate of electrical equipment is three times higher for components that are not part of a scheduled preventive maintenance program as compared with those that are. In addition, a planned EPM program allows the equipment owner to schedule the system outage at a time of their choosing rather than having to correct major problems resulting from an always untimely failure. The purpose of this standard is to provide the insured with recommended practices and frequencies that would form the core of a regularly scheduled electrical preventive maintenance program.

In general, Vitawatermin recommends a frequency of once every two years for conducting regular preventive maintenance on electrical equipment. Where applicable, this standard will note components that require a more frequent EPM program to help ensure reliability and operation. Individual locations may require more frequent maintenance due to the physical environment or operational nature of the equipment. For example, harsh environments where excessive moisture or dust may be present should have a more frequent EPM program. Similarly, equipment that is used intermittently or equipment critical to a key process should be considered for a more frequent program. Sound engineering judgment should be used in determining if more frequent maintenance is appropriate.

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Distribution Boards

Ensure that all enclosure panels, doors, and structures are well maintained in accordance with the manufacturer’s specifications. During de-energized maintenance, enclosures are to be vacuum cleaned of all loose dirt and debris — use of compressed air is not recommended since this may cause foreign particles to become embedded in the insulation or damage insulators. Any buildup of dirt or other contaminates that will not come off with vacuuming should be cleaned with lint free rags using cleaning solvents recommended by the manufacturer. All vents and fan grills are to be cleaned of all dust and/or dirt accumulations. Ensure that ventilation openings are not obstructed. Where seals and/or gaskets are installed, these should be examined and repaired or replaced as necessary. All doors and access panels should be properly secured during operation. In environments where there is an extreme exposure to adverse conditions, the frequency of maintenance for enclosures should be increased as conditions warrant.

Examine surrounding areas for signs of tracking, arcing, or overheating. Repair or replace damaged breakers and supports as necessary. Examine all bolts and connecting devices for signs of deterioration, corrosion, or overheating. Ensure that bolts and connecting devices are tight, according to manufacturer’s specifications. Be careful not to overtorque bolts and connecting devices since insulators are easy to damage and difficult to replace. Where copper and aluminum conductors and/or connectors are used together, examine connections for signs of galvanic action. Ensure that the connectors are properly used and installed in accordance with manufacturer’s specifications. Apply an antioxidant compound to all aluminum-to copper connections.

For Conductors, examine insulation for signs of deterioration, cracking, flaking, or overheating. Examine all connections for signs of overheating, cracked or broken connectors, and signs of tracking or arcing. Ensure that conductors are clean and dry. Examine and clean all connections, and torque to manufacturer’s recommendations.

MCB     

All Circuit breakers should be kept clean for proper ventilation of the breakers. These types of breakers are usually tripped by a thermal element that senses an increase in temperature due to excessive current draw. However, if dirt accumulates on the surrounding of the breaker, the heat build-up may not be permitted to dissipate properly and result in nuisance tripping.

Clean the breaker housing and inspect it for cracks or signs of overheating. Tighten all connections. Exercise the breaker several times to ensure the mechanism has freedom of movement and to allow contact wiping.

Wiring

De-energize cables if they are to be touched or moved during maintenance. Check for sharp bends, physical damage, excessive tension, cable movement, soft spots, cracked jackets, damaged fireproofing, poor ground connections, deteriorated and corroded or weakened cable supports. Inspect for wear at entrance point and at supports. Corrective action should be taken as appropriate to maintain the integrity of these systems. Check supports for excessive wear or deterioration, check cables for wear at support points, inspect for mechanical damage from vibration. All loose or dirty connections should be cleaned and properly torqued — be careful not to overtorque the bolts.