Transformer Grounding

[Gerry de Pedro]

Why is it , for switchgear used as sevice equipment, wherein neutral and equipment groud are bonded,that you have to provide grounding electrode conductor connected from the ground electrode to the service equipment ground bus or neutral ground bus while another is to be provided at the Transformer neutral at Y-secondary side since the neutral of the transformer is already bonded to the switchgear bus thru the Neutral conductors? Is this for testing and security purposes that just in case that one equipment grounding conductor opens , you still have another one?

 

[iwire]

Re: Transformer Grounding

Most of the time the service transformer is under NESC requirements and does not exist in the NECs world.

Second if it is a privately owned transformer grounding electrodes are required, think of 480-208Y/120 SDS in a building they are already grounded but still need a grounding electrode installed.

[ September 08, 2005, 10:34 AM: Message edited by: iwire ]