Dry-Type Transformer Enclosures

3 replies [Last post]
meby's picture
Joined: 2012-04-17

The 2014 Edition of the NEC now requires a terminal bar be secured inside the transformer enclosure for all bonding and grounding conductor connections. What effect will this have on your installation practices? Will it save you any time or money?

skd76's picture
Joined: 2013-09-11

Logical requirement. It is cetrtainly possible to install open lugs on the bottom or sidewall of the xfmr. It is often done poorly. Hope is that the xfmr mfr will step up and provide a bar (similar to an intersystem bond bar - but larger) in the xfmr. Intermediate fix will be to install at time of xfmr wiring with an aftermarket device.
Mr. Eby, may I suggest that when one throws a new or little-known Code rule out for discussion, that they include the section number"(s) as a part of the topic question? Perhaps that should be in the What you need to know...Read-me-1st postings"? Or as a flyer on the "New Topic" initial post page?
New forum tool is quite welcomed! Thanks.

meby's picture
Joined: 2012-04-17

Hi, skd76. Thanks for your response to my post.

Your suggestion to include the actual Code reference in my original post makes perfect sense. I typically do so, but obviously missed the mark this time around. This new requirement can be found in Section 450.10 of the 2014 NEC.

Your suggestion to add this tip to our rules list is a great idea. I'll pass that along to our Forum Administrator.

I'm also happy to hear you like the new forum on our site.


Joanie's picture
Joined: 2015-05-27

Lately, some of our engineers have tried to establish a design rule that a pad-mounted transformer require a ground rod at each corner and connection by a 2/0 ground wire, creating a ground loop around the transformer. I do not believe this is necessary. I also believe that it has the effect of transferring the single point ground for the facility from the service entrance location (a ground rod outside) to the transformer, no matter how far away.

What are your thoughts?

Thank you!

Please or Register to post comments.

What you need to know?

1. Forum Rules 2. Forum Login


Featured Video

Join the Discussion on EC&M Talk
EC&M Learning Center

Connect With Us

Sponsored Introduction Continue on to (or wait seconds) ×