Preventive Maintenance

Preventive maintenance is recommended by many organizations.

InterNational Electrical Testing Association Inc. (MTS-2001 Appendix B Frequency of Maintenance Tests)

recommends for average equipment conditions and medium equipment reliability that electrical equipment be tested from every 2 months for Functional testing of Emergency Systems to every 36 months for Cables. 

National Fire Protection Association, (in 70B-2002, Electrical Equipment Maintenance, Chapter 4)

tells why an electrical preventive maintenance program pays dividends. Article 4.2.1 says “A well-administrated EPM program will reduce accidents, save lives, and minimize costly breakdowns and unplanned shutdowns of production equipment.  Impending troubles can be identified – and solutions applied – before they become major problems requiring more expensive, time-consuming solutions.”(NFPA statment.doc)

Institute of Electrical and Electronic Engineers (ANSI/IEEE Std. 493-1997, page 292, appendix C, table 2.)

This says that the average cost per square foot of a business interruption is $0.681.  Note this was printed in 1997 and would be even more now.

The same standard on page 258, appendix A, table B states that if you perform annual energized testing (including infrared testing) and de-energized testing as well as cleaning and torquing connections, the statistical risk of failure is reduced by 67%.

National Fire Protection Association (ANSI/NFPA 70B, 1994; page 8, 2-2.8.)

This states that if you do energized testing, including infrared testing, your statistical risk of breakdown and fire resulting from your electrical equipment drops by 50%.

ANSI/NFPA 70B-2002; page 11, Figure 4.2.6

Shows the relationship between the time interval between EPM inspections and annual cost for the EPM cost, Cost of equipment repair and replacement and cost of both.  It shows that frequent inspections gives the minimum total cost.

            ANSI/NFPA 70B-2002; page 107, Table A.4.2.8

Shows the results of a 2 year study by Factory Mutual that indicates one-half of the losses associated with electrical equipment failures might have been prevented by an effective EPM (Electrical Preventive Maintenance) program.

            ANSI/NFPA 70B-2002; page 173, Annex I

Give maintenance intervals for informational purposes only with references.