Minimum Insulation Resistance Test Results

Perform a time resistance testing method using a megger and take successive readings at specific intervals.

Minimum insulation resistance test results.

The measured resistance indicates the condition of the insulation between two conductive parts. What affects insulation resistance readings. 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. Insulation resistance is temperature sensitive.

Electrical testing with the use of electrical test meters including. 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. Do not touch or move conductor during testing as results will be affected.

230v to measure insulation resistance in ohm s. Do not allow the leads to touch during the test. The results obtained from ir test are not intended. This is one factor that generates the continued popularity of analog testers.

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. 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. Insulation resistance decreases in temperature or moisture.

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. Insulation resistance testing path can affect the test and reduce the insulation resistance reading. The megger insulation tester is a small portable instrument that gives you a direct reading of insulation resistance in ohms or megohms. To give you the correct answer i need to find the old megger insulation testing booklets i bought via ebay some years ago.

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. A time resistance test is performed over five to 10 minutes. 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. This test is to make sure that the electrical insulation material surrounding the conductors is intact.

Suspend and isolate the test set leads in air as much as possible. The measurement of insulation resistance is a common routine test performed on all types of electrical wires and cables.