Occupant access to service disconnect?

Status
Not open for further replies.
I recently replaced a main breaker panel for a condo owner where the existing panel was main lug only (It needed replacement because a breaker malfunctioned and melted, damaging 2 adjacent breakers, one of the buss bars and the feeder conductor). The building has an electrical room where the feeder disconnects to each condo unit are located. The room is locked and only accessible to building maintenance/management personnel. The staff is only on site Mon-Fri from 8am-5pm.
My question is whether I'm reading and/or understanding article 225.35 (Access to Occupants) correctly?
My understanding is that "......these are under continuous building management supervision......." means 24/7 or at all times and on site.
I mentioned the situation to the city inspector who inspected my work. He said it's not a violation because the management company has an after hours number where someone can be reached, even though they're not on site.
My concern is that if any emergency occurs on a weekend, holiday or in the middle of the night, it may be compounded because of the delayed response time of the management company.
If anyone knows the exact intent of the code-making panel, when they wrote "Continuous", I would greatly appreciate it.
 
as long as supervised maintenance responds to 24/7 conditions the code is met

That is why I asked if anyone knows the exact intent. I'm sure that the CMP chose the word "continuous" for a good reason. Seems to me that if management is not "on site" then supervision is no longer continuous. Saying that having an after hours number meets code, seems like an ambiguous interpretation. What about the timeliness of the response in case of an emergency? If it takes an after hours technician a half hour to an hour, to show up and cut the power, it may be too late in an emergency. I may be wrong, but I'm just trying to understand that particular article, the exact intent and the reason for the way it's worded.
 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Retired Electrical Engineer
Let's all back up a half step.
The building has an electrical room where the feeder disconnects to each condo unit are located.
This sentence seems to be telling me that in the electrical room is a feeder breaker, and that the other side of that feeder is a circuit breaker panel located inside the individual condo. Is that right? If so, you have already complied with the code. What 240.24(B) requires is that the occupant have access to the breakers that protect the conductors that supply loads within their space. The occupant does not also have to have access to the upstream feeder breaker. That is because the conductors that are being protected by the upstream feeder breaker are not within the occupant's space.

 
Let's all back up a half step. This sentence seems to be telling me that in the electrical room is a feeder breaker, and that the other side of that feeder is a circuit breaker panel located inside the individual condo. Is that right? If so, you have already complied with the code. What 240.24(B) requires is that the occupant have access to the breakers that protect the conductors that supply loads within their space. The occupant does not also have to have access to the upstream feeder breaker. That is because the conductors that are being protected by the upstream feeder breaker are not within the occupant's space.

Allow me to clarify the situation. The electrical room is over 100 feet away. The feeders do pass through not only this occupant's space, but also 2 other occupant spaces. Article 240.24 (B) Requires that occupants have ready access to all overcurrent devices protecting the conductors supplying that occupancy. Not just for branch circuits but also the feeders that supply the occupancy. Article 240.24 (B) (1) (2) Provides an exception if ......"electrical maintenance is provided by the building management and where these are under continuous building management supervision." This brings me to the same question I had in the original post, What is the meaning of continuous supervision?
 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Retired Electrical Engineer
Thank you for the clarification. Now I will add a clarification of my own.
The electrical room is over 100 feet away. The feeders do pass through not only this occupant's space, but also 2 other occupant spaces. Article 240.24 (B) Requires that occupants have ready access to all overcurrent devices protecting the conductors supplying that occupancy (I added the emphasis). Not just for branch circuits but also the feeders that supply the occupancy.
A feeder that passes through one tenant's space on its way to a different tenant's space is not supplying the first tenant's occupancy. Therefore, the first tenant need not have access to the overcurrent device that protects that feeder. A receptacle outlet on the first tenant's wall receives its power from a circuit breaker located in a panel that is inside that same tenant's space. That tenant therefore does have access to the overcurrent device that protects the conductors that are supplying that outlet. That is all that the code requires.

 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Retired Electrical Engineer
My concern is that if any emergency occurs on a weekend, holiday or in the middle of the night, it may be compounded because of the delayed response time of the management company.
My response is that the absence of electrical energy in a private residence is not an "emergency." It is merely an "inconvenience." This is not, for example, a hospital, where loss of electrical power in the middle of an operation could conceivably lead to a person's death. So if a feeder breaker were to trip, leaving a tenant without power in their unit, the tenant is welcome to go to bed and wait for daylight, or pick up the cell phone and call the management's after hours number. Or they can leave the building and wander the streets just for the exercise. In the meantime, the tenant is not in danger of dying from the lack of electricity. As I see things, if there is no real and present threat to life and limb, you are not dealing with an "emergency."
This brings me to the same question I had in the original post, What is the meaning of continuous supervision?
I tend to agree with what several others have said: A 24/7 response number that will reach a person who is awake (or would be awakened by the call) will satisfy the requirement.
 
My response is that the absence of electrical energy in a private residence is not an "emergency."

However presence of electrical energy when you don't want it could be an emergency (such as melting breakers in a MLO panel). That sounds like the OP's situation.

It seems to me that if the condo's panel is MLO, then quick/on-demand access to the supply feeder breaker might be required, but if the condo's panel does have a main the requirements are covered. By quick-access, I'm thinking of maybe 5-10 minute response, not 4 hour response. 'course if there's an active fire, the FD will usually open doors without waiting for a key.
 
However presence of electrical energy when you don't want it could be an emergency (such as melting breakers in a MLO panel). That sounds like the OP's situation.

It seems to me that if the condo's panel is MLO, then quick/on-demand access to the supply feeder breaker might be required, but if the condo's panel does have a main the requirements are covered. By quick-access, I'm thinking of maybe 5-10 minute response, not 4 hour response. 'course if there's an active fire, the FD will usually open doors without waiting for a key.

You are correct Zbang, that is exactly the point I'm trying to make. The emergency is a main lug panel in a melt down situation where power can't be be removed in an emergency. Yes I know that it the case of a fire, the FD will get into the electrical room but isn't it better to avoid the problem to begin with instead of waiting for the FD. Isn't that the purpose behind the Code to begin with?
 
Thank you for the clarification. Now I will add a clarification of my own. A feeder that passes through one tenant's space on its way to a different tenant's space is not supplying the first tenant's occupancy. Therefore, the first tenant need not have access to the overcurrent device that protects that feeder. A receptacle outlet on the first tenant's wall receives its power from a circuit breaker located in a panel that is inside that same tenant's space. That tenant therefore does have access to the overcurrent device that protects the conductors that are supplying that outlet. That is all that the code requires.


I understand that the feeder that passes through the other occupants is not supplying those other occupants and I never said that those other tenants should have access to the overcurrent device for that particular feeder. I apologize for the confusion, I only mentioned it to provide additional information and add clarification, since a previous response stated that the feeders were not passing through the final occupant's space. I was just saying that the feeders are passing through the occupant's space as well as other's spaces. I have to disagree with your interpretation of Article 240.24 (B). The wording, supplying the occupancy, means the feeder as well. 240.24 (B) (1) specifically mentions Service and Feeder Overcurrent Devices.
 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Retired Electrical Engineer
I have to disagree with your interpretation of Article 240.24 (B). The wording, supplying the occupancy, means the feeder as well. 240.24 (B) (1) specifically mentions Service and Feeder Overcurrent Devices.
Yes, the feeder conductors do supply the occupancy. So do the service conductors. So do the overhead conductors that originate from the substation 20 miles away. So do the generator output conductors located at the hydro power station 300 miles away. I maintain that none of this falls within the intended scope of 240.24(B). There are buildings throughout the country that have locked electrical rooms that have distribution panels with feeder breakers that serve individual branch circuit panels in individual tenant spaces. The tenants can access the branch circuit breakers that supply loads within their unit. That is the extent of the requirement. The tenants are not required to also have access to the distribution panel (and its feeder breakers) in the locked electrical room. That is actually a good thing, as the tenants are likely to be unaware of what to do in that room.

When 240.24(B)(10 talks about feeders, it refers to a single overcurrent device that protects a single feeder that supplies more than one occupancy. You don't come across that very often. But you would not want any one of the tenants supplied by that feeder to be able to turn it off, thus removing power from the other tenant(s). So you make it accessible only to building management. Similarly, the main breaker at the main service panel supplies more than one tenant space. Here again, you don't want the tenants to have access to that breaker.

 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Retired Electrical Engineer
You are correct Zbang, that is exactly the point I'm trying to make. The emergency is a main lug panel in a melt down situation where power can't be removed in an emergency.
In such an instance, the tenant's only safe strategy is to grab all humans and exit the building, leaving pets and property behind. They have no business trying to terminate the event by asking building management to open the electrical room door and turn off power to their unit. Even if the tenant's circuit breaker panel is not MLO but has a main breaker, it would not be safe for them to open the panel door and reach over to open the main breaker. Also, even if they could successfully remove power (either at their own panel or at the upstream feeder breaker), this may not prevent a fire from starting. This is a job for the fire department.

 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
When 240.24(B)(1) talks about feeders, it refers to a single overcurrent device that protects a single feeder that supplies more than one occupancy.
Doesn't the existence of 240.24(B)(1) imply that feeder breakers that supply only a single occupancy fall under the general 240.24(B) requirement?

Cheers, Wayne
 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Retired Electrical Engineer
Doesn't the existence of 240.24(B)(1) imply that feeder breakers that supply only a single occupancy fall under the general 240.24(B) requirement?
I think not. The words include "feeder overcurrent devices supplying more than one occupancy."

 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
I think not. The words include "feeder overcurrent devices supplying more than one occupancy."
Right, that's the wording from 240.24(B)(1), so those feeder OCPDs are exempt from the general 240.24(B) requirement if they meet the special requirements of 240.24(B)(1). The usual implication is that other feeder OCPDs are subject to the general 240.24(B) requirement.

Cheers, Wayne
 
Status
Not open for further replies.
Top