L-G Megger Readings

[PhaseShift]

If I wanted to perform L-G megger readings on a grounded wye connected transformer, do I need to remove the grounding connection at the wye point in order to perfrom these L-G readings?

What if the wye was on the primary of the transformer?

Thanks for the help.

 

[zog]

If I wanted to perform L-G megger readings on a grounded wye connected transformer, do I need to remove the grounding connection at the wye point in order to perfrom these L-G readings?

What if the wye was on the primary of the transformer?

Thanks for the help.

Yes you need to lift the ground connection.

 

[PhaseShift]

Yes you need to lift the ground connection.

This would apply for a 240/120 center tap grounded as well as delta corner grounded transformer as well?

The current would travel from the megger through the continuity where phase leg is connected to ground then through ground back to the megger thus completing the circuit?