Understanding 225.30

[Ohms law]

If you install a subpanel (or any other type of OCPD in the supply conductors, with the exception of a supplementary OCPD) then the supplying conductors would be a feeder... so the exception would not apply.

This is perfect, I was just trying to understand this whole 225.30 section. I had a question about disconnecting means. If you read 225.31 then read 225.32 ex.1 it seems to me it is saying you don't need a main breaker panel for a disconnect you could get away with a main lug panel in detached garage fed from house. Ex. 1 is saying under single management, as in the homeowner. Right?

 

[Smart $]

This is perfect, I was just trying to understand this whole 225.30 section. I had a question about disconnecting means. If you read 225.31 then read 225.32 ex.1 it seems to me it is saying you don't need a main breaker panel for a disconnect you could get away with a main lug panel in detached garage fed from house. Ex. 1 is saying under single management, as in the homeowner. Right?

Uhhh... no! How many homeowners do you know that have documented safe switching procedures, and are qualified to monitor the installation???

 

[Ohms law]

Uhhh... no! How many homeowners do you know that have documented safe switching procedures, and are qualified to monitor the installation???

Ok, I'm just asking. Hypothetically, if they had safe operating procedures. Why would the homeowner monitor the equipment? Would they to just call a qualified electrician?

 

[jumper]

Ok, I'm just asking. Hypothetically, if they had safe operating procedures. Why would the homeowner monitor the equipment? Would they to just call a qualified electrician?

The exception would require it to be done and the HO calling an electrician when there is a problem does not qualify.

Exception No. 1: For installations under single management,
where documented safe switching procedures are established
and maintained for disconnection, and where the
installation is monitored by qualified individuals, the disconnecting
means shall be permitted to be located elsewhere
on the premises.

There is no residential or average commercial application that this exception would apply to.

Personally I cannot think of an application that this would apply to nor do I care to, the only way I would even think of not putting a disconnect is if an EE signed and sealed a drawing with plan review passed.

My advice, just ignore this exception.

 

[GoldDigger]

My advice, just ignore this exception.

Unless you find yourself drowning between a rock and a hard place and need a lifeline. (Mixed metaphor intended.)

 

[Dennis Alwon]

I move these posts because the thread they were in was about 250.30 so I started a new thread

 

[GoldDigger]

I move these posts because the thread they were in was about 250.30 so I started a new thread

But kept the "Understanding 250.30" title....

 

[Dennis Alwon]

The thing that makes this difficult is where does it state that the disconnect must be on the separate structure? 225.32 says inside or outside of the structure not on the structure then the exception seems to infer it must be on the structure.

Disconnects for trailers are allowed 30' from the trailer. Services are also stated inside or outside the building--- Can I have the disconnect for the house 30' away? It is not clear

 

[Dennis Alwon]

But kept the "Understanding 250.30" title....

I don't think so...

 

[roger]

The exception would require it to be done and the HO calling an electrician when there is a problem does not qualify.



There is no residential or average commercial application that this exception would apply to.

Derek, I do know of it being used/done on a University Campus. They had written proceedures in place for the electrical staff.

Roger

 

[Ohms law]

The exception would require it to be done and the HO calling an electrician when there is a problem does not qualify.



There is no residential or average commercial application that this exception would apply to.

Personally I cannot think of an application that this would apply to nor do I care to, the only way I would even think of not putting a disconnect is if an EE signed and sealed a drawing with plan review passed.

My advice, just ignore this exception.

So, after reading from the NEC handbook, it actually states Ex.1 only applies to commercial, industrial, and institutional occupancies.

 

[Smart $]

So, after reading from the NEC handbook, it actually states Ex.1 only applies to commercial, industrial, and institutional occupancies.

Ultimately it can apply anywhere... but the likelihood of a residential property qualifying is very, very close to, if not absolutely zero probability.

 

[kwired]

Ultimately it can apply anywhere... but the likelihood of a residential property qualifying is very, very close to, if not absolutely zero probability.

Except maybe at the homes of maintenance workers that follow a pretty good safe switching procedure program at their place of work. Some of those guys maybe actually wear proper PPE for tasks even at home, and maybe even at least consider getting permits for hot work, confined spaces, and so forth, then say wait a minute, since I am at home I'm the one that has to approve or deny this request, or maybe the wife does, but all she will care about at the time is that the task gets done and will approve the permit.