New Termination Point for Bare Copper #6 EGC Coming from Ground Rod

[cbooker]

So my electrician got red tagged today, and 1 of the reasons was the inspector stated the bare copper #6 EGC going to the Ground Rod is suppose to be terminated at the neutral bus on the Transfer Switch. Inspector stated that this is a new requirement in the Code. The transfer switch's Neutral is Bonded to Ground inside the switch so technically no big deal. However, it still doesn't sound right to Terminate the EGC at neutral bus and not on the actual Ground Bus inside the Switch. The "new code" the inspector is referencing sounds a bit strange to me if that truly is a new Code Requirement. Anybody here ever heard of the new code requirement for Terminating EGC at Neutral Bus for 1st means of disconnect on a single family residential dwelling?

 

[infinity]

The GEC has to be on the neutral bus unless the main bonding jumper is a wire or bus bar then it would be optional to land it on either bus.

 

[LarryFine]

The idea is to earth the service neutral, not the EGC system.

 

[ActionDave]

So my electrician got red tagged today, and 1 of the reasons was the inspector stated the bare copper #6 EGC going to the Ground Rod is suppose to be terminated at the neutral bus on the Transfer Switch. Inspector stated that this is a new requirement in the Code. The transfer switch's Neutral is Bonded to Ground inside the switch so technically no big deal. However, it still doesn't sound right to Terminate the EGC at neutral bus and not on the actual Ground Bus inside the Switch. The "new code" the inspector is referencing sounds a bit strange to me if that truly is a new Code Requirement. Anybody here ever heard of the new code requirement for Terminating EGC at Neutral Bus for 1st means of disconnect on a single family residential dwelling?

The #6 conductor going to the ground rod is a Grounding Electrode Conductor, not an Equipment Grounding Conductor and it is an ancient rule that it goes the same place that the neutral is bonded at the service.

 

[Dennis Alwon]

I believe this is the section

250.64(D)(3) Common Location.

A grounding electrode conductor shall be connected in a wireway or other accessible enclosure on the supply side of the disconnecting means to one or more of the following, as applicable:

• (1)
  Grounded service conductor(s)
• (2)
  Equipment grounding conductor installed with the feeder
• (3)
  Supply-side bonding jumper

The connection shall be made with exothermic welding or a connector listed as grounding and bonding equipment. The grounding electrode conductor shall be sized in accordance with 250.66 based on the service-entrance or feeder conductor(s) at the common location where the connection is made.

 

[infinity]

Don't these transfer switches usually have a wire type MBJ between the neutral and EGC bus? If so the GEC can terminate in either place.

 

[Chamuit]

Generac does, a #4 I think.

The last Kohler I did, did not. Must be relying on the can.

 

[Steve16]

Generac does, a #4 I think.

The last Kohler I did, did not. Must be relying on the can.

This is correct. I'm constantly inspecting installations in the field with these Kohler transfer switches and electricians landing the GEC and neutrals on the equipment grounding bar

 

[cbooker]

Don't these transfer switches usually have a wire type MBJ between the neutral and EGC bus? If so the GEC can terminate in either place.

Yes, if its not there, I make my guys put one there. Cummins and Generac come with an MBJ. Briggs and Kohler does not. Or atleast the ones that I have received from OEM dont have it installed.

 

[augie47]

I can see it being one of those areas subject to interpretation;

The Section Dennis quoted (Post#5) is in:
Building or Structure with Multiple Disconnecting Means in Separate Enclosures

On the other hand in 250.24 Grounding Service-Supplied Alternating-Current Systems
(1) General. The grounding electrode conductor connection shall be made at any accessible point from the load end of the overhead service conductors, service drop, underground service conductors, or service lateral to, including the terminal or bus to which the grounded service conductor is connected at the service disconnecting means.

In IAEI seminars I have heard it argued that connecting to any point beyond the neutral buss incorporates additional points of potential resistance in the event of a high current surge