9 service disconnects?

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JasonCo

Senior Member
Location
Houston, Texas
As of Friday, I was lined out on a job that I'm going to be starting Monday. Everything was drawn out and was explained with no confusion, it is cut and dry on what I am suppose to do. I just don't believe this will pass inspection, correct me if I'm wrong.

Here we go. I will have a parallel set of lateral conductors coming from the utility pole and up into a Tap box mounted to the back of a commercial multi-tenant shopping center. I will have a Gutter/trough nipped into the right side of this Tap box. From the tap box I will have 9 separate service entrance conductors going to 9 separate meter cans. All adjacent to one another. 6 of the meter cans will be mounted above the gutter with 6 service disconnects. The other 3 will be separately hard piped on the left side of the tap box and into 3 separate meter cans, and then they will feed into 3 separate panels with main breakers. Everything will be grouped together, all 9.

I'm almost certain this is code violation. You can only have 6 service disconnects grouped together in one "building"/structure/lease space. The other 3 will have to be piped over to a portion of the back wall that is separated by a firewall, because each lease space has a separate address and is separated by a firewall making them their own building/structure.

Only thing I am confused about is if this is okay to do? I'm pretty sure the 9 grouped together is a violation, but is it okay to hard pipe 3 of them off the tap box over to a different "building" and group the other 3 together in that section? Or do I need a totally separate set of service laterals going to the other 3 grouped on the wall in the other "building".

Here is a drawing I made to sort of show you visually what they want. The drawing is horrible, I would not mount my equipment in the way I drew it up haha. It's just to better show what my company wants to do, grouping all 9 together.

11.jpg
 

kwired

Electron manager
Location
NE Nebraska
Have to look but I believe that one service lateral can only supply one service.

If the additional items were say fire pump service, that has special permissions, but not acceptable for general purposes.

The other three on "separate building" or separate occupancy might be allowed, but would likely need additional underground to the pole to supply them and not come from the tap box in your drawing.
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
I think the drawing looks great. It’s certainly better than I could attempt to do..
230.71 says “in one location”

So what’s a location? The NEC doesn’t do a good job of defining location.
It does define building in saying a service is permitted per building, but...

So how far are the meters on the left from the tap box, and could it be called another “location”?

We have a strip mall here where there are 11 meters, each with disconnects. 6 in one “location”, 5 in the other “location”.
They are separated by 20’ total. 6 on one side of the tap box, 5 on the other side.

Not sure if there is a firewall on the inside of the building or not between these locations.

May be an AHJ call before it’s installed..
 

JasonCo

Senior Member
Location
Houston, Texas
In my understanding, a separate location is defined by the firewall that separates the locations/structure. It can physically be one building but with different addresses. Each address is separated by the lease space and the firewall inside that separates it from it's neighbors. So in my thinking, as long as I group the other 3 outside on the same wall, but I must pipe far enough over for it to be in another "structure", AKA interior firewall separating the two structures. This is the way I see it. In one of the old NEC codebook handbooks there is a drawing that sort of shows this.

5.PNG

With that said. Here is another drawing that confuses me. Anyone able to dissect this? Specifically where it talks about 230.40 Exception No. 1? The drawing is very confusing. You can't have 8 services in one location. I'm confused...

4.PNG
 

JasonCo

Senior Member
Location
Houston, Texas
Also just to throw more confusion into the matter. This photo is straight out of my POCO's Service Standards handbook. I see 7 services... HUH?

3.PNG
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
To me, and I’m really nothing, there are MUCH more knowledgeable people on here, in your drawing I see 9 service entrance conductors.
You don’t have more than one service disconnect per service conductor IMHO if the service point is the tap box.

Like I say, depending on the AHJ argument, it could fail as you said, but I see it as legal.
The original argument for the disconnects per service was in 1933 for adding panels for more appliances without having to add a new service.
So a meter, then no more than six disconnects. That doesn’t count for a disconnect then sub panel after.
It’s six disconnects per service.
 

JasonCo

Senior Member
Location
Houston, Texas
To me, and I’m really nothing, there are MUCH more knowledgeable people on here, in your drawing I see 9 service entrance conductors.
You don’t have more than one service disconnect per service conductor IMHO if the service point is the tap box.

Like I say, depending on the AHJ argument, it could fail as you said, but I see it as legal.
The original argument for the disconnects per service was in 1933 for adding panels for more appliances without having to add a new service.
So a meter, then no more than six disconnects. That doesn’t count for a disconnect then sub panel after.
It’s six disconnects per service.

Correct, I agree. There is 1 service lateral with 9 separate service entrance conductors. Like you said once the conductors hit the meter, it then creates the "service". It's only 1 disconnect per service, so it doesn't exceed 6. Although, sense there is more than 6 service disconnects for this 1 service lateral, I'm thinking I need a main disconnect before it hits the tap box. Maybe I'm wrong. Just waiting on more help because this is too complex haha.
 

kwired

Electron manager
Location
NE Nebraska
Correct, I agree. There is 1 service lateral with 9 separate service entrance conductors. Like you said once the conductors hit the meter, it then creates the "service". It's only 1 disconnect per service, so it doesn't exceed 6. Although, sense there is more than 6 service disconnects for this 1 service lateral, I'm thinking I need a main disconnect before it hits the tap box. Maybe I'm wrong. Just waiting on more help because this is too complex haha.
sort of. NEC doesn't really recognize the meter as anything significant it does recognize number of service disconnecting means there are though. You could have two main disconnects/circuit breakers after each meter - if so you have doubled the number of service disconnecting means.

Now since this application is multi occupancy you can have a service to each occupancy - fire walls aren't mentioned in NEC, but building codes will generally require fire walls anyway.

230.40 plus exception 1 supports what I mentioned earlier. One lateral to each occupancy or group of occupancies. I don't think you can run from the tap box would have to come from the source to each permitted service. Six disconnects at one location is one service (fire pumps, emergency systems, etc. may be additional disconnects beyond 6 that are allowed).

That said if POCO owns/maintains the line to the tap box, then you might be able to come from the tap box. That somewhat common in residential or lighter commercial where they may have multiple facilities on one transformer, some on common utility owned line to a splice box then runs to individual customers, and is definitely more common with a common line in overhead distribution systems, but still normally a single drop to a single service.
 

JasonCo

Senior Member
Location
Houston, Texas
I'm losing my mind the more I research this all. Everyone has a different answer to everything, I'm about to explode!

Now I'm reading that 1 service lateral is ONE service, or 1 service drop is ONE service. 2 service laterals would be TWO services, or 2 service drops overhead would be TWO services.... Then I also have people telling me, including my boss. Once the conductors hit the meter, this would be considered a service. So in my scenario, I have 9 services with 9 separate service entrance conductors. I just don't know what to believe anymore, this is actually insane.

@kwired, if you have six disconnects at one location, it's one service you are saying. Okay, but what if those 6 disconnects are on the load side of 6 separate meters with 6 separate service entrance conductors coming off that tap box. This would be 6 separate services the way my boss explains it, and like half the stuff I google. I'm so confused it's driving me insane
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
230.71(B) permits me to have up to six means of disconnect for each of the meters. Each meter (occupancy) is treated like a separate service because each meter is permitted to have a set of service entrance conductors by Exception #1 to 230.40.
However, there is still only one service, and the language in 230.71, in the 2017 and older codes says you can only have a maximum of six service disconnects "grouped" in a single location.

The issue becomes what does "grouped" mean. Is the original sketch a group of 9 service disconnects, or is it two separate groups, one of 3 service disconnects and one of 6 service disconnects.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
I'm losing my mind the more I research this all. Everyone has a different answer to everything, I'm about to explode!

Now I'm reading that 1 service lateral is ONE service, or 1 service drop is ONE service. 2 service laterals would be TWO services, or 2 service drops overhead would be TWO services.... Then I also have people telling me, including my boss. Once the conductors hit the meter, this would be considered a service. So in my scenario, I have 9 services with 9 separate service entrance conductors. I just don't know what to believe anymore, this is actually insane.
...
You very clearly have one service that is supplying multiple sets of service entrance conductors per Exception #1 to 230.40.
 

kwired

Electron manager
Location
NE Nebraska
I'm losing my mind the more I research this all. Everyone has a different answer to everything, I'm about to explode!

Now I'm reading that 1 service lateral is ONE service, or 1 service drop is ONE service. 2 service laterals would be TWO services, or 2 service drops overhead would be TWO services.... Then I also have people telling me, including my boss. Once the conductors hit the meter, this would be considered a service. So in my scenario, I have 9 services with 9 separate service entrance conductors. I just don't know what to believe anymore, this is actually insane.

@kwired, if you have six disconnects at one location, it's one service you are saying. Okay, but what if those 6 disconnects are on the load side of 6 separate meters with 6 separate service entrance conductors coming off that tap box. This would be 6 separate services the way my boss explains it, and like half the stuff I google. I'm so confused it's driving me insane
read exception 2 to 230.40. as well as the part in 230.2 that mentions 230.40 exception 2.

After taking all that in we can say:

One service lateral, which can have an unlimited number of parallel elements because paralleling essentially is still treated as one conductor, but you must join both ends together or it is not paralleling - that one lateral is allowed to supply one service that has up to six service disconnecting means.

If there is six sets of conductors running from the source (tied together at source end) to six separate disconnecting means at one location that is still considered one service.

Meters mean nothing, been said by a member here years ago it is just a wide point in the conductors. You could have a facility with CT metering on/near the transformer and still supply multiple services from the meter - like say a campus type situation with multiple buildings or a farmstead with multiple buildings.
 

kwired

Electron manager
Location
NE Nebraska
230.71(B) permits me to have up to six means of disconnect for each of the meters. Each meter (occupancy) is treated like a separate service because each meter is permitted to have a set of service entrance conductors by Exception #1 to 230.40.
However, there is still only one service, and the language in 230.71, in the 2017 and older codes says you can only have a maximum of six service disconnects "grouped" in a single location.

The issue becomes what does "grouped" mean. Is the original sketch a group of 9 service disconnects, or is it two separate groups, one of 3 service disconnects and one of 6 service disconnects.
I think he is fine with original sketch other than he likely needs to run the supply to the pole and not the tap box. He will then end up with two groups of six or less disconnects, and like I said the meters mean almost nothing in determining what is a service, it is the service disconnecting means that determine that. Is possible to have more than one disconnect per meter - they all count.
 

JasonCo

Senior Member
Location
Houston, Texas
So basically what you are saying is that it is not code compliant. I have more than 6 disconnects for this one service inside this one "grouped location".

So how do you resolve this when you have a commercial multi-occupancy building with 9 lease spaces, each lease space has it's own address and each is considered a separate structure/building. I would have to run another service lateral to a different lease space where I can install the last 3 which is what you are saying?

The part where you say "he likely needs to run the supply to the pole and not the tap box.", I'm not understanding.

Also thank you all for your time and effort on this, something I very much needed!
 

kwired

Electron manager
Location
NE Nebraska
So basically what you are saying is that it is not code compliant. I have more than 6 disconnects for this one service inside this one "grouped location".

So how do you resolve this when you have a commercial multi-occupancy building with 9 lease spaces, each lease space has it's own address and each is considered a separate structure/building. I would have to run another service lateral to a different lease space where I can install the last 3 which is what you are saying?

The part where you say "he likely needs to run the supply to the pole and not the tap box.", I'm not understanding.

Also thank you all for your time and effort on this, something I very much needed!
Your existing lateral is supplying "one service" that consists of six service disconnecting means" grouped at one location.

If you run from the tap box the lateral will be supplying two different services - that doesn't comply with 240.40 or any of it's exceptions.

Possibly gets clouded some if tap box actually belongs to the POCO, then you possibly can connect there. I'd be talking to both POCO and AHJ about this before making final design decisions.
 

JasonCo

Senior Member
Location
Houston, Texas
Just so I can further learn what you are saying. If I can only have up to 6 disconnects per service. What if I just add a main disconnect before the tap box and this would make it so there is 1 disconnect controlling this service? Then off this one main service disconnect I can hit the tap box, then off to an unlimited amount of meters and disconnects. I guess I'm just getting confused on when a service ends so I don't have to worry about the 6 disconnect rule anymore.

Also, if this is true. In my case this main disconnect would have to be GFCI protected, being over 1000Amps? Thought I read that somewhere...
 

kwired

Electron manager
Location
NE Nebraska
Just so I can further learn what you are saying. If I can only have up to 6 disconnects per service. What if I just add a main disconnect before the tap box and this would make it so there is 1 disconnect controlling this service? Then off this one main service disconnect I can hit the tap box, then off to an unlimited amount of meters and disconnects. I guess I'm just getting confused on when a service ends so I don't have to worry about the 6 disconnect rule anymore.

Also, if this is true. In my case this main disconnect would have to be GFCI protected, being over 1000Amps? Thought I read that somewhere...
If you put a main at the tap box then everything beyond that is a feeder. You would need to separate grounded and equipment grounding conductors. If it is on/in a building the GEC must go to the service disconnect if it is not on the building then the building is supplied by a feeder which kicks in art 225 part III which is still feeders but with many similarities to things in art 230. GEC in each separate building runs to the first disconnecting means at each building.

GFCI is the 4-6 milliamp trip threshold for personnel protection.

There is "ground fault protection of equipment" required for 1000 amps or more on wye systems that operate over 150 volts to ground. So if this is 480/277 system that would apply, 208/120 does not apply. See 230.95.
 
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