Based on Article 230.40 Ex. 1, each occupant of a multi occupancy building is permitted to have a set of Service Conductors run for his/her occupancy. The Code goes on further to say that this set of Service Conductors is limited to six Service Disconnects located in one location 230.71(A) and 230.72(A). Now the question: If I have this situation and we have a central location for the utility supply, can each of these occupants have their Service Disconnects (up to six) located near the Service Point and exceed the magic number of six? In other words, occupant #1 has four Service Disconnects on his Service Conductors and occupant #2 has four Service Disconnects on his Service Conductors. Both of these occupant's Service Disconnects are properly identified as to load served etc.and are located in the same general area. Is this a problem from a Code stand point or a safety hazard?

George
Look on pages 129-130-131 N.F.P.A. N.E.C.
Code Handbook 2002.Exhibit 230.13. Not Code section. Exhibit(Illustration)Page 131

Note Handbook not Code book.

230.40 Ex1 deals with services of differnt voltages or phases.

I have no idea what pages 129, 130, or 131 have to do with this. Is that from the 2002 NEC?

Service entrance conductors are the conductors that are fed from the POCO overhead or underground feed. (See the definition in article 100) There are only Six disconnects maximum (six hand movements) allowed to turn off the power.

Service Disconnect isn't defined in Art. 100 by that title, but as I understand it, it is AKA a "main"... the "numero uno" breaker (residential min 100A), that, by being turned off, kills power to all of the branch circuits contained in the same panel (main breaker style), or any panels "downstream" from it's location if remote...say at the meter.

Four Service Disconnects for one residence? Am I missing something?

Russ M
Code are pages from the N.F.P.A. Electrical Code HANDBOOK Not Code book 2002. The pages deal with service entrance conductors underground and overhead in Pictures!!!!It Does apply and deals with the six disconnect rules. Maybe you should expand your Libary a bit. The book is put out by the NFPA same ones who do the code.

Doug if I remember you are a Chicago resident?

If so you may have some different rules for this.

But the NEC allows up to 6 (7 if there is a fire pump) disconnects for the "service disconnect" to a structure.

There are a lot of ways this could happen, one way would be a 320/400 meter socket feeding four 100 amp main breaker panels side by side.

Each one of the 4 breakers is a service disconnect.

In commercial applications service conductors may enter a piece of service rated switch gear with no single main.

In that switch gear you might install six 800 amp breakers giving you 4800 amps of service with out the need of a very expensive 480 volt 4800 amp GFP main breaker unit.

Bob

Chicago code 6 six disconnect rule is, 18-27-230-71
Number of Services 18-27-230.2
Number service entrance conductors 18-27-230.40
2002 Chicago Electrical Code

Thanks Yoopersup.

Bob

yoopersup:

All you had to say, was that it was from the 2002 NEC Handbook.

I understand the "rule of six" per structure (230 (F) in the 96 NEC). It just seemed like the question had multiple service disconnects for one residence in a multi-occupancy structure.

The question seemed to be awkwardly worded - Even though term service disconnect was being used, it seemed to me that George could be inadvertantly referring to branch circuits for each occupancy within a multi occupancy structure, rather than "main d/c's" that would control power to a sub-panel located inside each occupancy.

That's why I was surprised/confused.

BTW - I second the recommendation for the NFPA Code Handbook. EXCELLENT reference / explanatory material.

I dont have a bible (code book) handy and i am not the most well versed in multiple disconn-multi services, but my understanding is that you are allowed 6 throws of the hand per service not per structure. that an apartment building with 24 apartments in it and all of the meters and individual disconnects all in one grouping is legal as they are all for indavidual services ie 24 services not 24 disconnects

[disclaimer]The views expressed within are, of course, just my personal interpretation of The 1996 Code - when in doubt, ask your AHJ![/disclaimer]

Yes, sparkystudent, if you had 24 separate drops, you could have 24 separate disconnects - but you can't have that many drops/laterals to a single structure.

The general instruction in the Code is:


The Code does allow multiple services for Multiple-Occupancy buildings by special permission facing space constraints(230-2 Ex.3), and for Buildings of Large Area that need two or more services (230-2 Ex. 5).

The Code also goes on to restrict the number of Service Entrance Conductor Sets served by Drops or Laterals to one per Conductor Set, unless it is 2 to 6 service disconnecting means grouped at one location (230-40 Ex. 2), which once again seems to stick to the "rule of 6", which is reinforeced by:


Looking back at the original post, I think the idea of the Code would be for EACH Occupancy to have a SINGLE means of disconnection of ALL ungrounded conductors with a SINGLE motion, no matter how many occupancies are in the structure. If the occupancies share a service drop/lateral, then only six of those occupancies can share that source, and be grouped together in any one location.

It would be ideal to have a structure (building service) disconnect, then occupancy disconnects, then branch circuit disconnects, but it looks like it is allowable to have the building service (if it is six or less occupancies) divided amongst the services for the occupancies, and ultimately disconnected by "six motions or less".