Based upon equipment rating.
Insulation resistance test values as 3000.
At a pressure of 1000 v applied between each live conductor and earth for a period of one minute the insulation resistance of hv installations shall be at least 1 mega ohm or as specified by the bureau of indian standards.
Curve a shows test values as measured.
The dc current is typically in the tens of microamps.
If the test voltage is 3000 then the test current would be 3000 250 x 0 5 or 6 ma.
If the test is dc then the current during the test is a function of the insulation resistance of the system including the insulation resistance of the stray capacitance and the y capacitors.
The results obtained from ir test are not intended.
Historically many field electricians use the somewhat arbitrary standard of 1 megohm per kv.
B kv is the rated machine terminal to terminal voltage.
Since 80 of electrical maintenance and testing.
For low voltage installations i e.
The insulation resistance test is an electrical test which uses a certain type and level of voltage 500v d c.
The insulation resistance test is the second test required by the electrical safety testing standards.
Values based on ieee std 43 2013.
Figure 4 typical record of insulation resistance of a mill motor.
As per ie rules 1956.
As a production test this test is often used as a customer acceptance test with minimum insulation resistance per unit length often specified by the customer.
1k v 1 mω minimum 1kv 1 mω 1kv.
One meg ohm rule for ir value for equipment.
Hands down without a doubt one of the most universally searched topics on ec m s website from a historical perspective is insulation resistance testing as a result some of our most popular evergreen articles like understanding insulation resistance testing continue to top the charts when it comes to most popular content.
Also acceptable values of insulation resistance depend upon the equipment you re testing.
230v to measure insulation resistance in ohm s.
Curve b shows same values corrected to 20 c see page 22 giving a definite downward.
3 shows a typical scale which reads increasing resistance values from left up to infinity or a resistance too high to be measured.
Developed early in the 20th century the insulation resistance ir test is the oldest and most widely used test for assessing the quality of insulation.
Correct procedures aimed at those whos just done it and passed cheers this official sponsor may provide discounts for members.
The measurement of insulation resistance is a common routine test performed on all types of electrical wires and cables.
A rated line to line voltage for three phase ac machines line to ground voltage for single phase machines and rated direct voltage for dc machines or field windings.
Hey could some explain how to do an insulation test to niceic test standards of how you should do it when your being assesed.
Ansi neta mts 2015 table 100 11 insulation resistance test values rotating machinery for one minute at 40 c.
