new 1200 amp service 480 volt

[LBSHEAR]

to pass code do i have to have a 1200 amp switchgear or can i just use a 1200 amp fusable disconnect any ideas ???

 

[iwire]

to pass code do i have to have a 1200 amp switchgear or can i just use a 1200 amp fusible disconnect any ideas ???

You will need to provide ground fault protection somehow.

 

[infinity]

You will need to provide ground fault protection somehow.

Bob,
Wouldn't that only apply to a WYE system?

 

[iwire]

Bob,
Wouldn't that only apply to a WYE system?

I don't have my book so I do not know, but I do assume it is a wye.

 

[LarryFine]

You will need to provide ground fault protection somehow.

Wouldn't the use of two 600a switches avoid that requirement?

 

[augie47]

Wouldn't the use of two 600a switches avoid that requirement?

Or a 1200 MLO with no breakers over 1000. Anthing that prevents you from having a OCP of 1000 amps or greater.
(Solidly grounded wye systems)

 

[ron]

No code book handy, but I would put GFP for 3 wire or 4 wire. Either way, you need to protect those darn electrons from going ungrounded to ground(ed)(ing) conductors.

 

[LarryFine]

Or a 1200 MLO with no breakers over 1000.

That's what I had in mind. It got misdirected on the way to the fingers.

 

[infinity]

Here's the requirement:

215.10 Ground-Fault Protection of Equipment.
Each feeder disconnect rated 1000 amperes or more and installed on solidly grounded wye electrical systems of more than 150 volts to ground, but not exceeding 600 volts phase-to-phase, shall be provided with ground-fault protection of equipment in accordance with the provisions of 230.95.
FPN: For buildings that contain health care occupancies, see the requirements of 517.17.

 

[zog]

to pass code do i have to have a 1200 amp switchgear or can i just use a 1200 amp fusable disconnect any ideas ???

Either but you need GFP as the code guys pointed out, most people use a bolted pressure switch (or "pringle switch") for this application with a GF panel, easy stuff we stock hundreds of these packages ready to go.

 

[texassparky]

Well Chalk that one up to Learn Something New Today....

That what I like about this forum, as soon as you think you know the answer and look it up to give a reference, sometimes you find you don't know what you thought you knew at all :grin:

For some reason in my mind, it said 250v but obviously not, 100 volts makes a big difference, but it sure seems like I have done 208 systems without GFP..

Now for a theory lesson please.. What do you get with a Delta that you don't with Wye, that makes GFP required on a wye...

 

[masterinbama]

Wouldn't the use of two 600a switches avoid that requirement?

You could use an 800 and a 400 ,3-400's or even 6- 200's

 

[augie47]

You could use an 800 and a 400 ,3-400's or even 6- 200's

or...they fly in the ointment, if load calculations allowed, you could even have (6) 400's. (or any combination). There is no requirement that the sum of the breakers remain at or below the 1200 amps.

 

[iwire]

or...they fly in the ointment, if load calculations allowed, you could even have (6) 400's. (or any combination). There is no requirement that the sum of the breakers remain at or below the 1200 amps.

I agree, we did a 480 wye service for a building that used 1200 amp MLO switch gear that contained 5 service disconnects that totaled over 3000 amps, none of them had to be GFP.

 

[infinity]

For some reason in my mind, it said 250v but obviously not, 100 volts makes a big difference, but it sure seems like I have done 208 systems without GFP.

Are you saying that you've installed GFP on 208 volt systems? I've yet to see that.