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XFMR Connection

jar546

CBO
Joined
Oct 16, 2009
Messages
12,816
Location
Not where I really want to be
How do you connect your transformers?

4e3f45fe.jpg
 
I don't see a grounding electrode conductor and I am having a hard time seeing the system bonding jumper connection.

Chris
 
I would also wager that the supply side bonding jumper (formally known as the equipment bonding jumper) is not sized properly. It seems quite small.

Chris
 
raider1 said:
I don't see a grounding electrode conductor and I am having a hard time seeing the system bonding jumper connection.Chris
jar546 said:
Yes, me neither
Looks like there is an empty lug on X0 right under X2. Maybe the installer isn't finished yet.:lol:
 
No, system bonding jumper.

No, grounding electrode conductor

The supply side bonding jumper appears to be too small.

Someone needs a lesson in 250.30. :)

Chris
 
Let me paint a better picture.

The system bonding jumper IS from the first disconnect as allowed, HOWEVER, it is useless because the GEC is off the frame of the XFMR.

They are going to remove the system bond from the main disconnect and place it from XO to the XFMR frame ground, then move the initial connection point of the GEC from the XFMR frame to XO where there is a lug waiting for it. Another lug must be added to XO for the system bond jumper.
 
jar546 said:
So I have a question.Do you see more GEC's connected to the XFMR or to the first disco/panel on the secondary side?
Most of the time in my area the grounding and bonding is done at the transformer and not at the first disconnecting means. That is the way I preferred to do it when I was installing.

Chris
 
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