INSULATION RESISTANCE ....

Q. What is the need of doing insulation resistance test for bus bar?
A. In order to verify the electrical isolation between phase to earth,phase to phase.

•        while doing the megger, specify the temperature 

                  why,because  
                                       resistance ∝ 1 / temperature.



PROCEDURE:

1. Remove all external connections before conducting test.

2. Connect remaining phases (which are not going under test) to earth.

3. Confirm that no person in contact with cable are at other end.

4. Apply megger voltage to phase which is being under test.

5. Discharge the charge after test.

6. Repeat the same procedure for remaining phases (ex ..Y,B ).