Six disconnect rule: A question for 2017 NEC section 230.71

[fandi]

Hello All,

There’s a mixed use building (Residential + Retails) with a main service switchboard MSB: 4000A Bus, 208/120V 3 phase 4W, MLO (Main Lug Only)

MSB Feeder breakers:

1) 2500A CB to Fire Pump controller.
2) 800A CB to Residential meter banks RMB1
3) 1000A CB to Residential meter banks RMB2
4) 1000A CB to Residential meter banks RMB3
5) Meter + 600A CB to Commercial tenant 1
6) Meter + 400A CB to Commercial tenant 2
7) Meter + 200A CB to Commercial tenant 3
8) Meter + 2500A CB to House panel.
I don’t think there’s a violation of 230.71 (Six disconnect rule) for the 4000A MLO Main service switchboard MSB but I wonder if there’s a violation of 230.71 (Six disconnect rule) for the RMB1, RMB2, RMB3:

RMB1, RMB2, RMB3 are MLO switchboards and each of them a) feeds at least 7 residential units, b) has at least 7 residential meters and c) not in the same room with the 4000A MSB.

Can permanent labels be added at the MLO switchboards RMB1, RMB2, RMB3 to inform the firefighters (in case there a fire at the residential units) that the breakers shutting down the residential meter bank switchboards are at MSB two floors down from where the firefighters are?

Thanks.

 

[shortcircuit2]

Didn't California role out new title 24 on Janruary 1st with the 2020 NEC adoption?

 

[fandi]

Didn't California role out new title 24 on Janruary 1st with the 2020 NEC adoption?

Yes but this old project is under 2017 NEC cycle.

 

[Dennis Alwon]

Is this one service or more than one. Basically how many drops are there from the power company transformer. A picture would be helpful

 

[fandi]

Is this one service or more than one. Basically how many drops are there from the power company transformer. A picture would be helpful

Thanks. It's only one service at MSB.

 

[augie47]

The 230.71 rule is for services... You have only (1) service disconenct so the rest are feeder panels and the individual mains in MSB are sufficient for disconnecting provided all the panels are in/on the same building.

 

[jaggedben]

I don't see how it's not a violation. You described 8 breakers in an MLO service panel. The additional breakers after the residential meters are irrelevant if you're saying there's a circuit breaker upstream of each meter bank. The meter locations are irrelevant.

The 230.71 rule is for services... You have only (1) service disconenct so the rest are feeder panels and the individual mains in MSB are sufficient for disconnecting provided all the panels are in/on the same building.

Read it again, he never described (1) service disconnect. He said the main switchboard is MLO and listed (8) breakers in it. Those are all service disconnects if he described it accurately.

 

[augie47]

I don't see how it's not a violation. You described 8 breakers in an MLO service panel. The additional breakers after the residential meters are irrelevant if you're saying there's a circuit breaker upstream of each meter bank. The meter locations are irrelevant.


Read it again, he never described (1) service disconnect. He said the main switchboard is MLO and listed (8) breakers in it. Those are all service disconnects if he described it accurately.

Oppps...
Thanks... old age eyesight..
If MSB is MLO you definitely have a violation.

 

[jap]

I don't see how it's not a violation. You described 8 breakers in an MLO service panel. The additional breakers after the residential meters are irrelevant if you're saying there's a circuit breaker upstream of each meter bank. The meter locations are irrelevant.


Read it again, he never described (1) service disconnect. He said the main switchboard is MLO and listed (8) breakers in it. Those are all service disconnects if he described it accurately.

I agree.

This seems like a lot going on.

JAP>

 

[fandi]

Is this one service or more than one. Basically how many drops are there from the power company transformer. A picture would be helpful

1) To me the (3) 800A CB feeding the residential service meter banks so they are indirect service disconnects. So if we don't count the 2500A CB for the fire pump, that's (7) service meter disconnects on a MLO main service panel.

2) I'm curious that it's OK for the RMB 1/2/3 to be MLO even though they feed a bunch of service meters as long as there's disconnect somewhere to shut it down. In this case, the RMB switchboards are in different room and too many individual residential service disconnects ( >7) for the firefighters to shut it down fast enough. And there are no labels telling the firefighters to go to the MSB room somewhere in the building.

 

[augie47]

Are spots #1 & #2 both fire pump breakers ??

 

[jap]

Are you sure this is drawn correctly?

I would think the Meters for retail 1,2,3 and house panel would be CT'd.

Not feed through as drawn.

Regardless I'm seeing 7 movements and a Fire Pump Feeder.

JAP>

 

[fandi]

Are spots #1 & #2 both fire pump breakers ??

#1 is for fire pump breaker. #2, #3, #4 are for residential meter banks.

 

[fandi]

Are you sure this is drawn correctly?

I would think the Meters for retail 1,2,3 and house panel would be CT'd.

Not feed through as drawn.

Regardless I'm seeing 7 movements and a Fire Pump Feeder.

JAP>

That's what I see from the plan. The house panel CB actually feeds a downstream switchboard with a bunch of loads, not just regular house panel common lighting, laundry, etc. It's a big 2500A CB with its own meter.

 

[jap]

That's what I see from the plan. The house panel CB actually feeds a downstream switchboard with a bunch of loads, not just regular house panel common lighting, laundry, etc. It's a big 2500A CB with its own meter.

Awesome,,,

JAP>

 

[Dennis Alwon]

The fire pump does not count as one of the 6 circuit allowed however there still appears to be 7 others

 

[jaggedben]

The fire pump does not count as one of the 6 circuit allowed however there still appears to be 7 others

I was thinking this might be, but the code doesn't quite say that . If the pump were on a separate service (allowed by 203.2) then 230.72(B) requires it to be remote. 230.72(A) exception permits it to be remote from the others if it's one of the two to six. But I don't see anything that permits it to be #7 on the same service as six others.

 

[jaggedben]

View attachment 2563560

1) To me the (3) 800A CB feeding the residential service meter banks so they are indirect service disconnects. So if we don't count the 2500A CB for the fire pump, that's (7) service meter disconnects on a MLO main service panel.

There's nothing 'indirect' about it. They are service disconnects, because there's no other disconnect between them and the service point.

2) I'm curious that it's OK for the RMB 1/2/3 to be MLO even though they feed a bunch of service meters as long as there's disconnect somewhere to shut it down. In this case, the RMB switchboards are in different room and too many individual residential service disconnects ( >7) for the firefighters to shut it down fast enough. And there are no labels telling the firefighters to go to the MSB room somewhere in the building.

Yes it's totally okay. For what's relevant here, the meter banks could be any other type of distribution (subpanels).

You could leave the meters out of your diagram and it makes no difference to what your asking about. The NEC doesn't give jack squat about the locations of meters.

 

[fandi]

There's nothing 'indirect' about it. They are service disconnects, because there's no other disconnect between them and the service point.


Yes it's totally okay. For what's relevant here, the meter banks could be any other type of distribution (subpanels).

You could leave the meters out of your diagram and it makes no difference to what your asking about. The NEC doesn't give jack squat about the locations of meters.

For each residential unit meter, there's a service disconnect (circuit breaker in this case) in that meter box. We can ignore meters but there are service disconnects next to the meters.

 

[kwired]

For each residential unit meter, there's a service disconnect (circuit breaker in this case) in that meter box. We can ignore meters but there are service disconnects next to the meters.

take a look at art 100 and definition of definitions with the word "service" in them.

To the user yes this disconnects them from having electrical service, but to NEC there is an upstream service disconnect making what you keep questioning to be "feeders" from NEC perspective.