Service disconnects

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Jpflex

Jpflex

Electrician big leagues
Location
Victorville
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Electrician commercial and residential
This is a service panel with a main 200 ampere disconnect. There are 3 of 2 pole breakers inside but does the maximum 6 disconnect rule within a single enclosure for services apply to two pole breakers (2 breakers with a common tie) count as 1 or two breakers for the no more than 6 disconnects per service?
 

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Clarify: I meant does the 2 pole breakers count as 1 or two disconnects each for this service? Even though they two breakers combined as 1
 
Strathead said:
Doesn't the 200 amp disconnect disconnect power to the bus? If so, that is only one throw the other breakers don't count.
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Yea the rule on 6 disconnects is confusing. The 200 ampere main disconnect feeds the busses A and B so does this rule mean 6 independent disconnects line side of service?
 
roger said:
If they are tied or a multipole, they are one.
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But these are not considered as part of the 6 max service disconnect rule? So I can put any number of breakers after main 200 ampere breaker within this service to feeders?
 
Jpflex said:
But these are not considered as part of the 6 max service disconnect rule? So I can put any number of breakers after main 200 ampere breaker within this service to feeders?
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Correct and correct.
 
So how would six service disconnects be set up then? Would there have to be a tap or buss for paralleling from service conductors to have parelleled sets of service conductores to terminate in individual breakers/ switches at individual switch disconnect cabinets or a single cabinet or how would the six disconnects for services be ran normally?
roger said:
Correct and correct.
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A main lug only panel with 12 slots was a typical 6 disconnect disconnecting means with 6 two pole breakers filling all the slots. But that isn't allowed anymore since service disconnect breakers need to be in their own enclosure. It could also be 6 panels like you have above side by side -- so 1200 amps of disconnecting means split across six 200A main panels. This latter case can have taps off the large service conductors feeding each 200A panel (although the utility may not want an installation where there is an openable box with taps ahead of the meters -- too easy to steal power).
 
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Jpflex said:
So how would six service disconnects be set up then? Would there have to be a tap or buss for paralleling from service conductors to have parelleled sets of service conductores to terminate in individual breakers/ switches at individual switch disconnect cabinets or a single cabinet or how would the six disconnects for services be ran normally?
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It could be:
1) tapped separate sets of service entrance conductors to different fused disconnects or single circuit breaker enclosures
2) under previous codes, a single main-lug panelboard or switch board with a bus fed directly by the utility and up to six switches or circuit breakers
3) under present code, a single piece of equipment similar to (2) with the switches or circuit breakers in separate compartments
4) Any combination of (1) with (2) or (3) such that the total disconnects are six or less

Any disconnect that doesn't have another disconnect on the utility supply side of it is a service disconnect. If a disconnect has another disconnect between it and the utility in series, then it's not a service disconnect.
 
suemarkp said:
But that isn't allowed anymore since service disconnect breakers need to be in their own enclosure.
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Wait. Are you saying that you can not feed a main-breaker in a panel anymore, or just that you can't have more than one main breaker per enclosure? The latter, I think.
 
This does make you think a bit. In the case of a main breaker, it is easy to tell you have one main breaker. But, in the case of a backfed main breaker, it may not be so easy to tell. And, if the position and/or labeling isn't all that clear, that makes it even harder to just look at and tell right off.
 
Before the 2020 code change most "Load centers" were not listed for use as service equipment unless a main breaker was installed, so you weren't going to comply with the listing if you fed a main lug panel and installed six mains. Some main lug commercial/industrial panelboards however were listed for that kind of application.

The old split bus panels when they were still allowed by NEC was a common method of having up to six mains in the panel. Then you ran into the occasional single pole breakers being installed in the mains section and that ended up violating the six mains rule.
 
wwhitney said:
2020 NEC 230.71(B)

Cheers, Wayne
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Obviously not a new code for 2020. Does anyone know when this was implemented? I have seen installations like iLine panels with no main installed as recently as around 2007. I never noticed this and wonder if I have violated it.
 
Strathead said:
Obviously not a new code for 2020. Does anyone know when this was implemented? I have seen installations like iLine panels with no main installed as recently as around 2007. I never noticed this and wonder if I have violated it.
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Most Main Lug Only panels have always been labeled SUSE (suitable for use as service equipment) when installed with 6 or fewer breakers.
It was the 2020 code change that ended this practice. My state is still.on the 2017 edition so these panels are still common.
 
So what
kwired said:
Before the 2020 code change most "Load centers" were not listed for use as service equipment unless a main breaker was installed, so you weren't going to comply with the listing if you fed a main lug panel and installed six mains. Some main lug commercial/industrial panelboards however were listed for that kind of application.

The old split bus panels when they were still allowed by NEC was a common method of having up to six mains in the panel. Then you ran into the occasional single pole breakers being installed in the mains section and that ended up violating the six mains rule.
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so if breakers are installed on the load side of a service main disconnect then these breakers cannot be one of the 6 main disconnects?

In order to be compliant with the code, 6 main breakers would have to be paralleled with the service entrance cables instead of being in series or fed from the service main breaker?
 
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