Maintenance electrical equipment

The electrostatic effect can be incorporated into wet scrubbing by charging the particulates and/or the scrubbing-liquor droplets. Electrostatic scrubbers may be capable of achieving the same efficiency for fine-particulate removal as is achieved by high-energy scrubbers, but at substantially lower power input. The major drawbacks are increased maintenance of electrical equipment and higher capital cost. 

NFPA 70B Recommended Practice for Electrical Equipment Maintenance. National Fire Protection Association, Quincy, MA. 

Electrical equipment Regular inspection and maintenance by qualified electricians Prohibition of makeshift installations... 

Removal of potentially contaminated equipment to workshop for maintenance, introduction of non-flameproof electrical equipment into a classified area. 

For facilities that include large numbers of motors and other electrical equipment, it normally is both more economical and more convenient to furnish a building to enclose the required motor starters and distribution panels. This building is normally referred to as a motor control center (MCC). In addition to typically allowing less expensive non-explosion-proof equipment, these buildings are frequently environmentally controlled (air conditioned, and possibly heated in colder climates) to reduce equipment corrosion and enhance reliability. Maintenance is more easily performed indoors than if the equipment were installed outside and maintenance personnel were subject to extreme cold, rain, snow, or other adverse weather conditions. 

Inclusion of thermography into a predictive maintenance program will enable you to monitor the thermal efficiency of critical process systems that rely on heat transfer or retention electrical equipment and other parameters that will improve both the reliability and efficiency of plant systems. Infrared techniques can be used to detect problems in a variety of plant systems and equipment, including electrical switchgear, gearboxes, electrical substations, transmissions, circuit breaker panels, motors, building envelopes, bearings, steam lines, and process systems that rely on heat retention or transfer. 

You will need to ensure that all plant and equpment (eg lift trucks, vehicles, gas appliances, machinery guarding, ladders, electrical equipment, lifting equipment, air receivers, ventilation plant) that requires maintenance (eg pre-shift checks, servicing, thorough examinations) is identified and that the maintenance is done. 

PM 82 The selection, installation and maintenance of electrical equipment for use in and around buildings... 

Permit-to-work systems See under Maintenance Entry into confined spaces (e.g. vat, vessel, flue, sewer, boiler or similar) Use of non-flameproof electrical equipment where flammable liquids/ vapours/dusts may arise... 

The team s expertise should be compatible with the kind of audit to be conducted. Audits of certain programs may require the selection of specialists in electrical equipment, pressure vessels, maintenance, motor fleet activities, and other fields. Line managers of other units are excellent members of audit teams. They bring a different background to spot weaknesses. In addition, participation is a learning experience for the manager and increases the involvement of those responsible for results. It may also be helpful to have a previous auditor of the unit as one member of the audit team. 

Division 1 locations are those places where ignit-able concentrations of flammable gases or vapors exist under normal conditions, or may frequently exist because of leakage or owing to maintenance operations, or where malfunctions may release ignit-able vapors and simultaneously cause failure of electrical equipment. 

A maintenance program should document all tests, inspections, and faults cleared by a main and feeder circuit breaker. Lack of such a program will reduce the reliability of the electrical equipment.Molded case circuit breakers require no internal maintenance. They should be inspected for broken casing and loose connections after they operate to clear a fault and should be replaced after they have operated to clear two faults. Feeder circuit breakers, especially older circuit breakers, should be exercised (repeatedly opened and closed) whenever possible.f" Part of the initial commissioning of an electrical power system must include testing of the ground fault protection. ... 

Class I Division 1 Locations in which ignitable concentrations of flammable gas or vapor can exist under normal operating conditions or can exist frequently because of repair, maintenance, or leakage or can be released during breakdown or faulty operation of equipment that might also cause simultaneous failure of electrical equipment such that the electrical equipment could become a source of ignition. 

It is also important that electrical equipment in hazardous areas should be properly maintained, particularly in older plants. Guidelines for maintenance of electrical equipment are given in standard NFPA 70B (2006). 

NFPA 70B (2006) Recommended practice for electrical equipment maintenance. (National Fire Protection Association). 

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