"Six Throws" Grouping of Service Disconnects via (6) Inside 42 Circuit Load Centers

cottora

Member
Location
Atlanta, GA
"Six Throws" Grouping of Service Disconnects via (6) Inside 42 Circuit Load Centers

I am a little confused about the six throws rule for service disconnect. I do not believe that all throws must be in a single enclosure, but I am not sure if a grouping of Main Breaker Panels is acceptable. Below is the general setup:

There will be six conductors/feeders that originate at the low side transformer and each conductor will land in a 600 amp Main Break Panel (each panel has ~42 circuits). These panels will be grouped inside and readily accessible (open the door and there they are on the back wall).

The be clear, you can essentially stand in one place, open six doors, throw six breakers, and all power in the building is disconnected.

Thanks!
 

jap

Senior Member
Is this not a continuation of a previous post about the Tap rule we recently discussed ?

JAP>
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Electrical Contractor
I am a little confused about the six throws rule for service disconnect. I do not believe that all throws must be in a single enclosure, but I am not sure if a grouping of Main Breaker Panels is acceptable. Below is the general setup:

There will be six conductors/feeders that originate at the low side transformer and each conductor will land in a 600 amp Main Break Panel (each panel has ~42 circuits). These panels will be grouped inside and readily accessible (open the door and there they are on the back wall).

The be clear, you can essentially stand in one place, open six doors, throw six breakers, and all power in the building is disconnected.

Thanks!
This install is compliant and will be the only acceptable means when the 2020 Nec become rule. When 2020 nec comes into effect you will not be allowed to have 6 breakers in one panel as satisfying your 6 disconnect rule.
 

cottora

Member
Location
Atlanta, GA
Is this not a continuation of a previous post about the Tap rule we recently discussed ?

JAP>
If need be I can move it there. But it is a totally different issue that is not contemplated in the previous post. That said, this business solution is derived from the knowledge of that post. Thanks
 

MAC702

Senior Member
Location
Clark County, NV
Are you sure you are talking about a service disconnect? In the NEC the Service Disconnect is a specific point and it is basically where the power company ends and the wiring inside the building starts?
Aren't you describing a service point? The "service disconnect" is quite often in a separate enclosure, fed by "service entrance conductors."
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
There will be six conductors/feeders that originate at the low side transformer and each conductor will land in a 600 amp Main Break Panel (each panel has ~42 circuits). These panels will be grouped inside and readily accessible (open the door and there they are on the back wall).
So these breaker panels are all services?
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
So the 6 panels are not service panels and do not contain the service disconnects? If that is true then the 6 throw rule is not applicable.
 

cottora

Member
Location
Atlanta, GA
So the 6 panels are not service panels and do not contain the service disconnects? If that is true then the 6 throw rule is not applicable.
That is correct. But I was under the belief that once you enter a building then you have to be able to cut power to such building within a prescribed way.
 

qcroanoke

Sometimes I don't know if I'm the boxer or the bag
Location
Roanoke, VA.
Occupation
Engineering
This install is compliant and will be the only acceptable means when the 2020 Nec become rule. When 2020 nec comes into effect you will not be allowed to have 6 breakers in one panel as satisfying your 6 disconnect rule.
What is the reasoning for that?
 

kwired

Electron manager
Location
NE Nebraska
So the 6 panels are not service panels and do not contain the service disconnects? If that is true then the 6 throw rule is not applicable.
6 throw rule still applies to the main disconnecting means of a building even if not service supplied.

His problem in that other thread is the need to land the taps at a single overcurrent device to comply with tap rules.
 

kwired

Electron manager
Location
NE Nebraska
What is the reasoning for that?
My guess, they decided they don't want people working in the enclosure that has live parts even with the main(s) off. Kind of lining up to some extent with 70E, though if it is critical to comply with 70E then maybe people were designing accordingly anyway.
 

jap

Senior Member
I have to say, I've never witnessed a service or a feeder to a building that was set up as (6) individual 600 amp Main Breaker 42 circuit panels grouped together as the disconnect.

Seems odd, but, to each his own.

JAP>
 

cottora

Member
Location
Atlanta, GA
I have to say, I've never witnessed a service or a feeder to a building that was set up as (6) individual 600 amp Main Breaker 42 circuit panels grouped together as the disconnect.

Seems odd, but, to each his own.

JAP>
For more background...This will be a bitcoin mining container (40 feet in length). So the six panels will land the conductors from the transformer and then these panels will branch off to feed ~1,000 outlets running down multiple rows of shelves. Each duplex outlet will be 208v with a 20 amp breaker from said panel. The outlets quad boxes will be fairly close together and running the length of the container on at least three rows.
 

jap

Senior Member
I'm having a hard time picturing this.

Are the 6 600 amp Panelboards located in one of the containers? or, are the 6 600 amp panelboards located in a warehouse and feeding several individual storage containers that have multiple 20a 3ph outlets and shelving installed inside of the individual containers ?

JAP>
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Electrical Contractor
I have to say, I've never witnessed a service or a feeder to a building that was set up as (6) individual 600 amp Main Breaker 42 circuit panels grouped together as the disconnect.

Seems odd, but, to each his own.

JAP>
NO you wn't see that but you could see 6 - 100 amp breakers or combination of any 6 breakers

What was common in our area was 100 to the sub panel, a 40 for the range, 30 for water heater, 30 for dryer, 30 or so for the a/c and 60 or so for heat strips. That would be your 6 disconnects on a 200 amp service. There was no way to work on the panel de-energized.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Electrical Contractor
BTW, My thinking is the OP had a 1600 amp service with 6 disconnects out of that sized probably 200 amps or so. Either that or he is building one huge service
 

jap

Senior Member
BTW, My thinking is the OP had a 1600 amp service with 6 disconnects out of that sized probably 200 amps or so. Either that or he is building one huge service
I'm with ya Dennis, but, go back and read his post #1.

It seems to be describing (6) 600 amp Main Breaker 42 circuit panels is what is being contemplated.

It's either that or the description is incorrect.

JAP>
 

jap

Senior Member
If we haven't seen one like this before , we're fixing to because that's what it sounds like is being designed to be built. :D

JAP>
 
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