In most markets, it is mandatory for a product to conform to safety standards outlined
by safety & standard agencies. And to conform to such standards, the product
must pass various safety tests such as Dielectric voltage-withstand test,
INSULATION RESISTANCE TEST -
The Insulation Resistance test detects insulation defects
by measuring the resistance. If the insulation resistance is sufficient (a value
specified by a standard), the equipment meets the requirements for preventing electric
shock and fire accidents.
The insulation resistance test does not substitute
the high voltage test. Effective insulation is a requirement to provide adequate
protection against direct contact, and to prevent the likelihood of short circuits
and earth faults. Faulty insulation can give rise to undue leakage currents and
can present a risk to persons and especially livestock. Obviously, faulty insulation
and the possibility of a spark give rise to the risk of fire. Many standards and
safety agencies have specified Insulation Resistance test as a 100% routine test
for all products. This test may be additionally carried out every time after a maintenance
procedure or repairing of a product is done or on a periodic basis. Some of the
more common causes of insulation failure include excessive heat or cold, moisture,
aging, corrosive atmospheres and vibration.
Insulation Resistance test gives an insulation value
usually in Megohms. Typically, the higher the insulation resistance values, the
better the condition of the insulation.
Although the Insulation Resistance test can be a predictor
of insulation condition, it does not replace the need to perform a dielectric withstand
test.