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don_resqcapt19

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electrofelon buddy I am just really confused at this point by NEC. Let’s say if what you say is correct then in attached sketch two services I have two electric utility transformers one 200A and another 800A both 480/277V three phase in commercial multioccupancy building each have one set of service entrance conductors in electrical room SWGRs which then serve group of occupancies. What’s to stop anyone from saying it’s per 230.40 exception no. 1 and thus it’s allowed?
In your sketch you have two services. Without a letter from the utility saying that they cannot supply a single 1000 amp service I am going to red tag that based on 230.2.
 

don_resqcapt19

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Definition of occupancy not specifically give in the NEC but inference from description in related portions of code can be made. Article 230 starts off restricting 1 service to a building in 230.2; in code reference to service conductors 230.70 a means to disconnect all conductors in a building from the service conductors, in 230.71(A) it further refers back to 230.40 including (exception 1) tieing a disconnecting means to service conductors and occupancies. Thus inference 1 disconnect 1 occupancy.
...
For the purposes of 230.40, I see occupancies as defined by the number of meters....each occupancy gets its own meter.
 

hhsting

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In your sketch you have two services. Without a letter from the utility saying that they cannot supply a single 1000 amp service I am going to red tag that based on 230.2.

Well yea but 230.40 exception one seems to allow it. Each service is as defined in 230.2 and one set of service entrance conductor run to each switchgear group of occupancies. It’s exactly what 230.40 exception one is saying. So what’s someone to say yea it’s two services but 230.40 exception no. 1 allows it?
 

Fred B

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Location
Upstate, NY
Occupation
Electrician
For the purposes of 230.40, I see occupancies as defined by the number of meters....each occupancy gets its own meter.
Figure 230.1 shows service entrance conductors post meter and disconnect(s) at or for occupancy(ies) and 230.40 refers to service entrance conductors not service conductors which are pre meter and is covered in 230.2.
 
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hhsting

Senior Member
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Glen bunie, md, us
Occupation
Junior plan reviewer
Definition of occupancy not specifically give in the NEC but inference from description in related portions of code can be made. Article 230 starts off restricting 1 service to a building in 230.2; in code reference to service conductors 230.70 a means to disconnect all conductors in a building from the service conductors, in 230.71(A) it further refers back to 230.40 including (exception 1) tieing a disconnecting means to service conductors and occupancies. Thus inference 1 disconnect 1 occupancy.


What your drawing appears to show maybe permitted not in reference to 230.40 but to 230.2(A),(B),(C),(D) but more specifically your statement indicating it might be covered in section 230.2(D) might be applicable.

Please re read that post #19 both services are same voltage, frequency and both three phase it won’t be allowed by 230.2(D).

The question was 230.40 exception no.1 seems to allow it. What language in 230.40 exception no. 1 does not support what is shown in attachment post #19?
 
What you are indicating is only 2 "occupancies" (points at which service conductor recieve a disconnect) 1 disconnect = 1 occupancy, after which it is no longer a service conductor under Article 230 just as @don_resqcapt19 indicated.
I'm not sure why you guys are not understanding the question. The question is: is installing SOME OF the service disconnects grouped together INSTEAD OF having them run to and located in their respective occupancies per 230.40 ex #1 ok? it's sort of using both exception 1 and 2 at the same time.
 

hhsting

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Glen bunie, md, us
Occupation
Junior plan reviewer
I'm not sure why you guys are not understanding the question. The question is: is installing SOME OF the service disconnects grouped together INSTEAD OF having them run to and located in their respective occupancies per 230.40 ex #1 ok? it's sort of using both exception 1 and 2 at the same time.

Ok but then how do you explain 230.40 exception no. 1 run one set of service entrance conductor run to group of occupancies? What install have you seen that? It’s hard to visualize
 
Well yea but 230.40 exception one seems to allow it. Each service is as defined in 230.2 and one set of service entrance conductor run to each switchgear group of occupancies. It’s exactly what 230.40 exception one is saying. So what’s someone to say yea it’s two services but 230.40 exception no. 1 allows it?

Now you have me also confused about what you are asking, but..... 230.40 ex 1 doesn't give you permission to have two services. It can be used IF you have two services however.
 
Ok but then how do you explain 230.40 exception no. 1 run one set of service entrance conductor run to group of occupancies? What install have you seen that? It’s hard to visualize
Three story building with 1 apartment on each floor and a house panel. I had one set go to a third story apartment, one to second story, and then the first floor panel and house panel were in the basement.
 

hhsting

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Location
Glen bunie, md, us
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Junior plan reviewer
Now you have me also confused about what you are asking, but..... 230.40 ex 1 doesn't give you permission to have two services. It can be used IF you have two services however.

Now I am confused. If I have new second service and arranged as shown post # 19 then what language in NEC 2014 Section 230.40 exception no. 1 allow or not allow that second service? 230.40 exception no.1 language fully supports post #19 attachment second new service.
 

don_resqcapt19

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Location
Illinois
Occupation
retired electrician
Well yea but 230.40 exception one seems to allow it. Each service is as defined in 230.2 and one set of service entrance conductor run to each switchgear group of occupancies. It’s exactly what 230.40 exception one is saying. So what’s someone to say yea it’s two services but 230.40 exception no. 1 allows it?
Nothing in 230.40 allows more than one service. Your example of of two utility transformers and 2 service laterals is two services and in general that is not permitted.

There is an issue with the code use of the term service vs the field use of the term.
Just because you have a multiple service disconnects does not mean you have multiple services. The general rule in 230.40 says that a service can only supply one set of service entrance conductors.

The exception permits a single service to supply any number of sets of service conductors. In general each occupancy gets a meter and each meter has a set of service conductors. Each set of service conductors is permitted to have up to six service disconnects. The service disconnects for that service must be grouped together. Service disconnects for one set of service entrance conductors are not required to be grouped with the service disconnects for any other set of service entrance conductors.
 

hhsting

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Location
Glen bunie, md, us
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Junior plan reviewer
Three story building with 1 apartment on each floor and a house panel. I had one set go to a third story apartment, one to second story, and then the first floor panel and house panel were in the basement.

Don’t follow what you tell me above is one set of service entrance conductor run to each occupancy. I understand that.

What I cannot visualize is one set of service entrance conductor run to group of occupancies??
 

Fred B

Senior Member
Location
Upstate, NY
Occupation
Electrician
Please re read that post #19 both services are same voltage, frequency and both three phase it won’t be allowed by 230.2(D).

The question was 230.40 exception no.1 seems to allow it. What language in 230.40 exception no. 1 does not support what is shown in attachment post #19?
230.2(D) also includes language stating: "....or for different uses...." but if the conditions of 230.2(A)-(D) cannot be met then 2 services cannot be done as attachment shows 2seperate services and "service conductors", 230.40 is speaking to "service entrance conductors", the code indicates a difference between the two. Minor difference of wording big difference in application.
1 service conductor to a meter then a split per 230.40 on the service entrance conductors that could go to seperate disconnecting or grouping of disconnects (or occupancies).
If you notice 230.30 speaks of "service conductors", 230.40 although "service entrance conductors". 2 seperate xfers and associated wire connector is a 230.30 application.
 

don_resqcapt19

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Location
Illinois
Occupation
retired electrician
Now I am confused. If I have new second service and arranged as shown post # 19 then what language in NEC 2014 Section 230.40 exception no. 1 allow or not allow that second service? 230.40 exception no.1 language fully supports post #19 attachment second new service.
The arrangement in post 19 shows two services. 230.2 does not, in general, permit more than one service. Nothing in 230.40 modifies the rule in 230.2 that only permits a singe service.
 

hhsting

Senior Member
Location
Glen bunie, md, us
Occupation
Junior plan reviewer
Nothing in 230.40 allows more than one service. Your example of of two utility transformers and 2 service laterals is two services and in general that is not permitted.

There is an issue with the code use of the term service vs the field use of the term.
Just because you have a multiple service disconnects does not mean you have multiple services. The general rule in 230.40 says that a service can only supply one set of service entrance conductors.

The exception permits a single service to supply any number of sets of service conductors. In general each occupancy gets a meter and each meter has a set of service conductors. Each set of service conductors is permitted to have up to six service disconnects. The service disconnects for that service must be grouped together. Service disconnects for one set of service entrance conductors are not required to be grouped with the service disconnects for any other set of service entrance conductors.

Your last paragraph I say there are cases where different service entrance conductors service disco are required to be group. 230.2 first paragraph exception says for 230.40 exception no.2 which is to group service disconnect of multiple service entrance conductors. How would you explain that?
 

Fred B

Senior Member
Location
Upstate, NY
Occupation
Electrician
The arrangement in post 19 shows two services. 230.2 does not, in general, permit more than one service. Nothing in 230.40 modifies the rule in 230.2 that only permits a singe service.
Correct, only one service unless stipulations of (A) to (D) of 230.2 could be met.
 

don_resqcapt19

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Location
Illinois
Occupation
retired electrician
Don’t follow what you tell me above is one set of service entrance conductor run to each occupancy. I understand that.

What I cannot visualize is one set of service entrance conductor run to group of occupancies??
I am not sure what the code means by "group of occupancies". It has no meaning to me. I apply the exception to 230.40 strictly based on the number of meters. Each meter has a set of service entrance conductors and up to six service disconnects.
 

don_resqcapt19

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Staff member
Location
Illinois
Occupation
retired electrician
Your last paragraph I say there are cases where different service entrance conductors service disco are required to be group. 230.2 first paragraph exception says for 230.40 exception no.2 which is to group service disconnect of multiple service entrance conductors. How would you explain that?
It only requires the service disconnects from one set of service conductors to be grouped with each other. There is no requirement that the service disconnects for service entrance conductor set #1 be grouped with the service disconnects for service entrance conductor set #2, or #3 or any other set. The only requirement is that all of the service disconnects for a single set of service entrance conductors be grouped with all of the other service disconnects for that same set of service entrance conductors.
 

hhsting

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Location
Glen bunie, md, us
Occupation
Junior plan reviewer
It only requires the service disconnects from one set of service conductors to be grouped with each other. There is no requirement that the service disconnects for service entrance conductor set #1 be grouped with the service disconnects for service entrance conductor set #2, or #3 or any other set. The only requirement is that all of the service disconnects for a single set of service entrance conductors be grouped with all of the other service disconnects for that same set of service entrance conductors.

what? Please see attachment we are talking about NEC 230.2 exception first paragraph part where it talks about For the purpose of 230.40 exception no. 2....?

So if I have from one utility transformer one set of service entrance conductor # 1 and from that same transformer second set of service entrance conductor #2 and third set of service entrance conductor #3 then their service discos #1,#2,#3 are not required to be grouped?

Please also see separate attachment NEC 2014 Exhibit 230.7 shows each service entrance conductor i.e service entrance conductor #1, #2 #3...shows them being grouped and mentions per 230.40 exception no. 2
 

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hhsting

Senior Member
Location
Glen bunie, md, us
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Junior plan reviewer
I am not sure what the code means by "group of occupancies". It has no meaning to me. I apply the exception to 230.40 strictly based on the number of meters. Each meter has a set of service entrance conductors and up to six service disconnects.

So if there are two meters then two occupancies? I just want to get that straight
 
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