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transformer grounding #77637
06/29/01 08:15 PM
06/29/01 08:15 PM
D
dom  Offline OP
Junior Member
Joined: Jun 2001
Posts: 8
When installing a 75kva dry type transformer,
(480delta-120/208wye) If using a water pipe as a ground electrode, does it need to be supplemented by another electrode? Would an equipment ground installed with the primary circuit feeding the transformer qualify as a supplementary ground electrode? thanks

2017 / 2014 NEC & Related Books and Study Guides
Re: transformer grounding #77638
06/29/01 08:28 PM
06/29/01 08:28 PM
S
sparky  Offline
Member
Joined: Oct 2000
Posts: 5,360
Hi dom!

450-10>>>250-20(d)>>>250-30(a)(2)

a start..

[Linked Image]

Re: transformer grounding #77639
06/30/01 07:19 PM
06/30/01 07:19 PM
R
resqcapt19  Offline
Member
Joined: Nov 2000
Posts: 2,148
IL
dom,
If the transformer feeder originates in the building service equipment, you can install the GEC in with the feeder conducotrs. See the exception in 250-30(a)(3).
Don(resqcapt19)


Don(resqcapt19)
Re: transformer grounding #77640
07/02/01 08:24 PM
07/02/01 08:24 PM
D
dom  Offline OP
Junior Member
Joined: Jun 2001
Posts: 8
Is there a different requirement for the ground electrode for the main switchgear(250-50) and a ground electrode at a transformer fed from a subpanel in the same system?(250-30(b)(2).- 250-30(a)(3).
thanks


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