Grounding at a "service entrance" when there is no service entrance
Grounding at a "service entrance" when there is no service entrance
(OP)
Hi there.
I'm working on a project performing a survey of grounding systems at a stand-alone facility in the middle of nowhere.
Since I'm still learning the nuances of grounding systems and their interfaces with power systems, I'm getting hung up on how to approach grounding the service entrance, when there is no service entrance.
My facility has no utility, but rather has a small power station, employing (4) 250kW diesel generators.
The generators are providing power to site facilities, and also to the building I am surveying (I am only surveying the one building).
Power leaves the power station, is stepped up to 7200 kV, travels, and is stepped back down to 208Y/120V at the building. From there it enters an ATS, and then into a primary distribution panel. My question is, for sites that have no service entrance, where should the neutral-ground bond be located?
Thanks.
AlaskaPE
I'm working on a project performing a survey of grounding systems at a stand-alone facility in the middle of nowhere.
Since I'm still learning the nuances of grounding systems and their interfaces with power systems, I'm getting hung up on how to approach grounding the service entrance, when there is no service entrance.
My facility has no utility, but rather has a small power station, employing (4) 250kW diesel generators.
The generators are providing power to site facilities, and also to the building I am surveying (I am only surveying the one building).
Power leaves the power station, is stepped up to 7200 kV, travels, and is stepped back down to 208Y/120V at the building. From there it enters an ATS, and then into a primary distribution panel. My question is, for sites that have no service entrance, where should the neutral-ground bond be located?
Thanks.
AlaskaPE






RE: Grounding at a "service entrance" when there is no service entrance
** I'm assuming you meant 7.2kV, not 7,200kV, which would be 7,200,000,000 volts!
"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington
RE: Grounding at a "service entrance" when there is no service entrance
RE: Grounding at a "service entrance" when there is no service entrance
RE: Grounding at a "service entrance" when there is no service entrance
Wroggent, that's what I initially thought as well, but wanted to get outside opinions/discussion.
RE: Grounding at a "service entrance" when there is no service entrance
BTW, 7200V is odd for a 3-phase distribution voltage. Are you sure it is not 12.47kV 3-phase 3-wire?
"I have not failed. I've just found 10,000 ways that won't work." Thomas Alva Edison (1847-1931)
RE: Grounding at a "service entrance" when there is no service entrance
RE: Grounding at a "service entrance" when there is no service entrance
In the Canadian code, When a utility supplies one of their own office buildings that building is subject to the code. Only generating plants, substations and similar facilities are exempt.
You are your own utility and you have a service entrance to the building. The generating plant may be exempt from the code.
Bill
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"Why not the best?"
Jimmy Carter
RE: Grounding at a "service entrance" when there is no service entrance
RE: Grounding at a "service entrance" when there is no service entrance
If the 208 Volt transformer is outside of the building the service entrance switch will be a Service Entrance Rated ATS.
Why an ATS inside the building?
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Grounding at a "service entrance" when there is no service entrance
RE: Grounding at a "service entrance" when there is no service entrance
Is one side of the switch unused?
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Grounding at a "service entrance" when there is no service entrance
RE: Grounding at a "service entrance" when there is no service entrance
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Grounding at a "service entrance" when there is no service entrance