Continuous ground

[ken44]

I have a 30kva xfmr being fed from a 1200 amp bus on a multi story commercial building and the xfmr supplying a 225 amp panel .
Does an EGC have to be continuous at the main service, in other words, can there be a continuation of the ECG by means of a ground lug, split-bolt or other similar means?
My inspector tells me that the wire must be continuous through XO to case or as an alternative, I must ground my neutral bus to the panel can.
One of us is confused, Can you please help?

 

[electricman2]

Re: Continuous ground

If you are asking can EGC conductors be spliced the answer is yes. For GEC conductors the requirements are more stringent.

EGC not ECG sorry

[ February 20, 2004, 12:01 PM: Message edited by: electricman2 ]

 

[ccha9219]

Re: Continuous ground

your panel after the xfomrer is considered a new service so your egc is common at xo on the line side you need an egc to your transfomer from eg bar at your source
ccha9219 daytona beach

 

[iwire]

Re: Continuous ground

Originally posted by ken44:
I have a 30kva xfmr being fed from a 1200 amp bus on a multi story commercial building and the xfmr supplying a 225 amp panel .
Does an EGC have to be continuous at the main service, in other words, can there be a continuation of the ECG by means of a ground lug, split-bolt or other similar means?
My inspector tells me that the wire must be continuous through XO to case or as an alternative, I must ground my neutral bus to the panel can.
One of us is confused, Can you please help?

I too am confused, I do not want be picky but your terminology seems a little off.

I would suggest you read 250.30 Grounding Separately Derived Alternating-Current Systems.

In short an equipment grounding conductor can be spliced as many times as you want.

It is a grounding electrode conductor that in most cases can only be spliced with irreversible means

The transformer requires it's own GEC conductor most times to building steel if there is some, if not you would have to run it back to the service GEC.

This is in addition to the EGC already at the transformer.

You must put in the bonding jumper from XO to the enclosure and the new grounding electrode.

As an alternative you could do this bonding at the first panel from the transformer.

Please take the time to read and understand the code section I pointed out, it is important to do this work properly.

 

[pierre]

Re: Continuous ground

ccha
The transformer in this example does not constitute another service. Article 100 defines a service as 'electrical energy from the serving utility'. This example is a separately derived system.
The GEC connection requirements are slightly different for a transformer supplied from the service, located within a building (as opposed to the service).
As Bob has stated it is very important to understand how this wiring is installed.

Pierre

 

[ken44]

Re: Continuous ground

Bob,
Many thanks for sorting through the confusion, it seems that the inspector and I were both confused but I am now "in the know"
after attending my 2002 Code Update Training. I was using the wrong terminology, I should have been referring to the GEC, not the EGC.
Ken