Transfomrer or First Disconnect?

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Transfomrer or First Disconnect?

  • Transformer

    Votes: 10 66.7%
  • First Disconnect

    Votes: 5 33.3%

  • Total voters
    15
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Mike01

Senior Member
Location
MidWest
Bonding preference:
@ the transformer?

@ the first disconnect?

Just curious on preferences / advantages / disadvantages to one vs. the other??
 

texie

Senior Member
Location
Fort Collins, Colorado
Occupation
Electrician, Contractor, Inspector
Bonding preference:
@ the transformer?

@ the first disconnect?

Just curious on preferences / advantages / disadvantages to one vs. the other??
I'm an "at the transformer" guy but I'm sure there as just as many who prefer the first disconnect.
 

MasterTheNEC

CEO and President of Electrical Code Academy, Inc.
Location
McKinney, Texas
Occupation
CEO
Bonding preference:
@ the transformer?

@ the first disconnect?

Just curious on preferences / advantages / disadvantages to one vs. the other??

Based on the question...are you asking for the preferred "Grounding" location versus a bonding preference. If this is the case I prefer at the XFMR.
 

John120/240

Senior Member
Location
Olathe, Kansas
I like the panel because of not having to separate the grounds and neutrals if you do it at the tyranny then you have to keep the grounds and neutrals separate at the panel.

I always understood that after the first OCPD we separate the grounds & neutrals. Sub panels for example. Is Wayne's way to avoid parallel ground paths ?
 

Lectricbota

Senior Member
Bonding preference:
@ the transformer?

@ the first disconnect?

Just curious on preferences / advantages / disadvantages to one vs. the other??


I prefer the panel.

I recently had an install where the transformer fed 2 services 500 feet apart. In that case bonding at transformer would have increased cost substantially.
 

Smart $

Esteemed Member
Location
Ohio
I prefer the panel.

I recently had an install where the transformer fed 2 services 500 feet apart. In that case bonding at transformer would have increased cost substantially.
In the case of a service transformer, IIRC, it only requires a single ground rod at/near the transformer... and there is no getting around it. Bonding is required both at the transformer and the service disconnects, and there is no supply-side bonding jumper (aka EGC) as the grounded conductor is used for bonding.

In case you meant a separately-derived-system transformer, it would just require a 2-ground-rod GES at the transformer and a single SBJ. A GEC from each building (as some believe to be the case) is not required... but a supply-side bonding jumper is no matter where the bonding takes place.
 

Tony S

Senior Member
I know I?ll use different terminology being British. I?m still struggling with some of your terms.

I mainly installed industrial power transformers and the N?E link would be at the incoming CB. Why, we used REF relays on all transformers and the tails would have some form of protection rather than just the O/C on the HV primary. Plus it was a matter of convention, everyone knew where it was.
 
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