Application Notes; Preventive Maintenance - Megger BM25 Guia Del Usuario

APPLICATION NOTES

Preventive Maintenance

The proverb 'A stitch in time saves nine' inspired the title of a Megger
Limited 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.
Megger supplies test record cards to assist with such record keeping, and
now with the BM25, the results can be downloaded directly to a computer.
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.
A number of these techniques have been automated on the BM25 to make
better use of your time and information. To help you get the most from
your BM25 we have included two short sections; firstly covering
Insulation Testing Concepts, then looking at the application of the
Test Record Example
different test techniques.
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