Minimum Insulation Resistance Test Results

Insulation resistance decreases in temperature or moisture.

Minimum insulation resistance test results.

What affects insulation resistance readings. Record the results at 60 seconds and then in 30 second intervals thereafter. The results obtained from ir test are not intended to be useful in finding localized defects in the insulation as in a true hipot test but rather give information on the quality of the bulk material used as the insulation. If the value returned is.

This test is to make sure that the electrical insulation material surrounding the conductors is intact. Do not allow the leads to touch during the test. 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. The megger insulation tester is a small portable instrument that gives you a direct reading of insulation resistance in ohms or megohms.

A time resistance test is performed over five to 10 minutes. Suspend and isolate the test set leads in air as much as possible. 230v to measure insulation resistance in ohm s. Electrical testing with the use of electrical test meters including.

Insulation resistance is temperature sensitive. The measurement of insulation resistance is a common routine test performed on all types of electrical wires and cables. Perform a time resistance testing method using a megger and take successive readings at specific intervals. First off there isn t a 1 mohm minimum insulation resistance for an existing installation when you are preparing an electrical installation condition report you need to make an engineering judgement as to whether the insulation resistance test result is acceptable.

This is one factor that generates the continued popularity of analog testers. Do not touch or move conductor during testing as results will be affected. Insulation resistance testing path can affect the test and reduce the insulation resistance reading. The measured resistance indicates the condition of the insulation between two conductive parts.

With a little record keeping and common sense however you can get a good picture of the insulation condition from values that are only relative. Winding insulation test primarily for non submersible type pump motors prep determine testing voltages determine minimum acceptable resistance at 40 c short all three phases together at terminals use a multimeter to measure resistance between the leads and grounded motor frame. As you gain more skills you ll become familiar with this behavior and be able to make maximum use of it in evaluating your test results. The insulation resistance test is an electrical test which uses a certain type and level of voltage 500v d c.

For low voltage installations i e. Even when not required by the end customer many wire and cable manufacturers use the insulation resistance test to track their insulation manufacturing processes and.