Application Notes; Preventive Maintenance - Megger BM11D Guide De L'utilisateur

Application Notes

Preventive Maintenance

The proverb 'A stitch in time saves nine' inspired the title of an
AVO International booklet on insulation testing, as it neatly
sums up the benefits of preventative maintenance. The savings
come in financial terms from costly repairs, lost production, lost
profits and in human terms, from lives saved in the event of
dangerous electrical faults.
Regular insulation testing of electrical equipment can help to
detect deteriorating insulation. The effects which cause
insulation to deteriorate include mechanical damage, vibration,
excessive heat or cold, dirt, oil, moisture and localized voltage
stresses - all of which can arise on most industrial or utility
equipment.
Insulation tests are sometimes used in isolation as absolute
measures of the quality of the insulation. This is most
appropriate when equipment is being installed and checked for
compliance with a specified 'Pass' level. For operational
equipment the key factors are trends in the insulation readings.
It is therefore important that records of insulation readings are
kept, relating to each piece of equipment or 'Asset' in your
testing regime. AVO supplies test record cards to assist with
such record keeping.
There are also a number of influences on the insulation
readings - temperature, humidity and surface leakage for
example and a range of test techniques have been developed to
help with the interpretation of your insulation tests.
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AVO INTERNATIONAL
Insulation Test Record
Equipment................................
Location ...................................
Test Record Example
N o. ................. Rating..............
Date installed ........................