Is main breaker required in apt. sub panel?

[ZZZ]

I was recently told by someone that the inspector in their town required a main breaker in the subpanels in multifamily apt. buildings. I didn't think 240.24 B required a main, although 230.72C could appear to have requirements for a "service" disconnecting means. This is a typical apartment installation with no continuous supervision or access by the tenants to the main service disconnects. Can someone clarify the requirements for a main breaker? Thanks

 

[danickstr]

Many feeder panels in apartments do not have mains at all, due to costs. And the main for the panel itself is often located in a room that the tenant cannot access, so that would seem to indicate no main disco necessary. I checked your two code references in my expanded 2005 and saw nothing about apartments and mains.

 

[brian john]

It would depend>

Is this a riser tap feeder? Then a main would be required.

If this is a single panel on a feeder with OCP in the electric room. I'd think not.

 

[mdshunk]

In addition to the riser tap mentioned, if the tenant doesn't have access to his main if it's in a meter stack in a locked room, he'd need a main in his panel. If it's just outside where he can get at it, then he can use an MLO panel.

 

[danickstr]

local codes can supersede NEC, so keep that in mind and make a call if you are in doubt.

 

[ZZZ]

In addition to the riser tap mentioned, if the tenant doesn't have access to his main if it's in a meter stack in a locked room, he'd need a main in his panel. If it's just outside where he can get at it, then he can use an MLO panel.

Marc,
It's not a riser tap, is the access requirement for a main breaker due to 230.72C?

-Randy

 

[charlie b]

. . . if the tenant doesn't have access to his main if it's in a meter stack in a locked room, he'd need a main in his panel.

I don't have my book at home, but I think this is not correct. Occupants must have access to overcurrent devices, but you can achieve that by having an MLO panel inside each unit.

 

[mdshunk]

Their main no longer an overcurrent device for some reason? Anyhow, check out 230.72(C). If there's not someone from the management company there 24/7 to unlock the main for the tenant, they need a main in their panel.

 

[resistance]

240.24(B): Each occupant shall have ready access to all overcurrent devices protecting the conductors supplying that occupancy. Exception No. 1: Where electric service and electrical maintenance are provided by the building management and where these are under continuous building management supervision, the service overcurrent devices and feeder overcurrent devices supplying more than one occupancy shall be permitted to be accessible to only authorized management personnel in the following:

(1)

Multiple-occupancy buildings

(2)

Guest rooms or guest suites of hotels and motels that are intended for transient occupancy

Exception No. 2: Where electric service and electrical maintenance are provided by the building management and where these are under continuous building management supervision, the branch circuit overcurrent devices supplying any guest rooms or guest suites shall be permitted to be accessible to only authorized management personnel for guest rooms of hotels and motels that are intended for transient occupancy.

 

[charlie b]

Their main no longer an overcurrent device for some reason?

Not my point. They don't have to have a main: that is my point. If it doesn't exist, then they need not have access to it. :wink:

If the resident has access to every OCPD that serves every branch circuit in their unit, then the requirement has been met. If the OCPD that protects the feeder to their panel is not accessible to the tenant, then that is not addressed by the requirement, and is therefore acceptable.

 

[resistance]

ROP:
240.24(B) Occupancy. Each occupant shall have ready access to all overcurrent devices protecting the conductors supplying that occupancy unless otherwise permitted in 240.24(B)(1) and (B)(2).
(1) Service and Feeder Overcurrent Devices. Exception No. 1: Where electric service and electrical maintenance are provided by the building management and where these are under continuous building management supervision, the service overcurrent devices and feeder overcurrent devices supplying more than one occupancy shall be permitted to be accessible to only authorized management personnel in the following:
(1) Multiple-occupancy buildings
(2) Guest rooms or guest suites of hotels and motels that are intended for transient occupancy
(2) Branch Circuit Overcurrent Devices. Exception No. 2: Where electric service and electrical maintenance are provided by the building management and where these are under continuous building management supervision, the branch circuit overcurrent devices supplying any guest rooms or guest suites without permanent provisions for cooking shall be permitted to be accessible to only authorized management personnel. for guest rooms of hotels and motels that are intended for transient occupancy.
Substantiation: The proposed revision to 240.24(B) is primarily editorial in nature seeking to eliminate exceptions by using positive text to improve clarity. The qualifier ?intended for transient occupancies? is deleted and the text in the proposed second level subdivision (B)(2) is modified to address ?guest rooms? and ?guest suites? with permanent provisions for cooking.
The exceptions are editorially eliminated and rolled into the positive text in two second level subdivisions.
The text in the present exceptions No. 1 & 2 which applies these rules to only guest rooms & guest suites ?intended for transient occupancies? is deleted. These terms, ?guest room? and ?guest suite? are now defined in Article 100. There is no longer a need for the qualifier ?intended for transient occupancy,? due to the addition of these definitions in Article 100 and qualifying requirements for ?guest rooms? and ?guest suites? in Article 210.
In essence the only difference between a ?guest room? or ?guest suite? and a ?dwelling unit? is a requirement for permanent provisions for cooking. Where a ?guest room? or ?guest suite? is provided with ?permanent provisions for cooking,? section 210.18 requires the following

 

[charlie b]

. . . check out 230.72(C). . . .

Perhaps tomorrow, when I can get at my code book again.

 

[ZZZ]

I don't have my book at home, but I think this is not correct. Occupants must have access to overcurrent devices, but you can achieve that by having an MLO panel inside each unit.

That would make sense to me but you can't always be sure of the intent of the code. Was it to allow the tennant to shut off the power to all breakers or just the individual circuits? I could see where a main breaker would be faster, or allow deenergizing a smoking breaker. But if speed was important, then the main disconnect outside would be almost useless to most tenants as they would never make the attempt. They would not even know the option was available. If it's for the Fire Dept., then locks and locked doors are not a deterrent as much as lack of signage as to which door to break down.

 

[resistance]

Perhaps tomorrow, when I can get at my code book again.

Here you go:
230.72(C)
Access to Occupants In a multiple-occupancy building, each occupant shall have access to the occupant's service disconnecting means.
Exception: In a multiple-occupancy building where electric service and electrical maintenance are provided by the building management and where these are under continuous building management supervision, the service disconnecting means supplying more than one occupancy shall be permitted to be accessible to authorized management personnel only.

 

[charlie b]

240.24(B): Each occupant shall have ready access to all overcurrent devices protecting the conductors supplying that occupancy.

The words I highlighted are key to this discussion, and may wind up being the reason my viewpoint may be wrong. I will have to see them, and the citation from 230, in complete context before I am certain. The question, IMHO, centers around whether the conductors from the panel (inside the unit) to all branch circuits (within the unit) are all that are intended to be covered by the words, "supplying the occupancy." An opposing viewpoint would be that the feeder to that panel is what is actually "supplying that occupancy," in the intended context, and therefore its OCPD must be accessible to the tenant.

 

[charlie b]

Here you go: 230.72(C)

OK. I surrender. That's what I get for trying to participate in the forum on weekends.

 

[resistance]

OK. I surrender. That's what I get for trying to participate in the forum on weekends.

Happens to me on a regular basis---surrendering that is! :grin:

 

[mxslick]

Here you go:
230.72(C)
Access to Occupants In a multiple-occupancy building, each occupant shall have access to the occupant's service disconnecting means.
Exception: In a multiple-occupancy building where electric service and electrical maintenance are provided by the building management and where these are under continuous building management supervision, the service disconnecting means supplying more than one occupancy shall be permitted to be accessible to authorized management personnel only.

Another fine example of the Code being clear as mud. :roll:

Read carefully the parts I highlighted. Does that mean that the building owner is now the POCO? In the literal sense that's what this wording says.

And even in a complex I had lived in where they had "management on site", there was a fire in one of the units, and the manager had NO CLUE as to where the main for that unit was located. The fire dept. found it almost at the completion of the fire fighting effort. (Fire was caused by meth lab gone wrong.) By the time they found it it had tripped anyway from internal damage to the panel.

Required by Code? In most cases, no. Good idea to have a main in each tenant's panel? Absolutely. And really, does a main breaker subpanel really cost that much more than a MLO? Not that I've seen around here anyway.

 

[iwire]

Good idea to have a main in each tenant's panel? Absolutely.

We will have to disagree there, I can't see that it really matters.

The FD would not hesitate to hit the building main if they really felt the need to turn off that unit.

 

[brian john]

60 amp main in the apt panel, then a 60 amp CB in the MDP located in a locked electric room. Problem occurs that trips the 60 amp main. Which one trips? The redundant 60 amp in the apt is serving no purpose.