Transformer bonding/grounding

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rich000

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Does anyone see an issue with this installation? The connection from neutral to the casing is shown in red. This was a factory connection. There is no "direct" connection from neutral to ground except through the casing. Would this be a violation? Or does it meet the intent? Thank you.

P.S. Sorry for the crude drawing. It was done in the field on the iPad.


note.jpg
 
pete m. said:
Take a look at 250.30(A)(1)(a)

Pete
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I am on 2008 code. There is no (a) on that. But 250.30(A)(1) says "System Bonding Jumper. An unspliced system bonding
jumper in compliance with 250.28(A) through (D) that is sized based on the derived phase conductors shall be used to connect the equipment grounding conductors of the separately derived system to the grounded conductor. This connection shall be made at any single point on the separately derived system from the source to the first system disconnecting means or overcurrent device, or it shall be made at the source of a separately derived system that has no disconnecting means or overcurrent devices."

The key words being "connect the equipment grounding conductors of the separately derived system to the grounded conductor" and "connection shall be made at any single point".

Am I interpreting that correctly? So my installation is unsatisfactory?
 
IMHO, I don't see an issue with the installation you have. I say this because it is common practice to use the enclosure as an EGC. I will have to do look a bit deeper at the connection for the GEC

Pete
 
I keep telling myself it is a violation, technically, because of the "single point connection" wording.
To be honest, I get lost in the system bonding jumper, equipment bonding jumper, etc. but I am of the belief that "single point" connections is necessary.
My thoughts may be biased one common grounding bar is commonplace here.
 
This installation is using the transformer case as the system bonding jumper. I don't see the case as being suitable to be used as the required system bonding jumper. 250.28.
 
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