702.5 Exception For Permanent Generator Provisions

[yesterlectric]

There's an exception to 702.5A that allows one not to have transfer equipment for installations where only qualified persons service the installation, for temporary connection of a portable generator. Is it thought that this provision simply allows one to bring a generator in and disconnect wiring to connect it; or is it commonly accepted that this provision would allow for someone to install PERMENANT provisions for the temporary generator (such as a power inlet and/or disconnect) without having to install a transfer switch?

 

[texie]

You can't permanently install a power inlet without some type of listed breaker interlock or a transfer switch. Lot's of buildings install permanent provisions for a roll up genset for standby use (702 loads) but will have some type of transfer switch or interlocked breakers. This is not what 702.5(A) Exception is referring to.

 

[yesterlectric]

You can't permanently install a power inlet without some type of listed breaker interlock or a transfer switch. Lot's of buildings install permanent provisions for a roll up genset for standby use (702 loads) but will have some type of transfer switch or interlocked breakers. This is not what 702.5(A) Exception is referring to.

So in your view the 702.5A exception is there to allow someone who never planned to, to install a generator if they have an outage? This being the case even though if someone wanted the power during an unexpected outage, they likely wouldn't check to see if the code allows them to have the power and would just think about how to safely isolate so they can have the power? And also, this being that 702.5 would prohibit this temporary connection except for installations where conditions of maintenance and supervision ensure that only qualified people access the installation (meaning: things like industrial installations).

Has anyone actually seen this be rejected or has anyone seen the transfer switch not be used? Your statement may be correct but if it is then 702.5 as written would prohibit any connection of a temporary generator during an outage unless you re-wire the entire system to have a transfer switch, or if you are a home owner, you before or during the outage construct things like locked equipment rooms in your house that only your electrical contractor has access to, to prohibit unqualified people from having access.

Thanks

 

[don_resqcapt19]

So in your view the 702.5A exception is there to allow someone who never planned to, to install a generator if they have an outage? This being the case even though if someone wanted the power during an unexpected outage, they likely wouldn't check to see if the code allows them to have the power and would just think about how to safely isolate so they can have the power? And also, this being that 702.5 would prohibit this temporary connection except for installations where conditions of maintenance and supervision ensure that only qualified people access the installation (meaning: things like industrial installations).

Has anyone actually seen this be rejected or has anyone seen the transfer switch not be used? Your statement may be correct but if it is then 702.5 as written would prohibit any connection of a temporary generator during an outage unless you re-wire the entire system to have a transfer switch, or if you are a home owner, you before or during the outage construct things like locked equipment rooms in your house that only your electrical contractor has access to, to prohibit unqualified people from having access.

Thanks

I would never consider this being permitted for a dwelling unit, even with a locked room.

An connection at a dwelling unit requires some type of transfer equipment. Most AHJs accept the commonly available breaker interlock kits as being suitable for use a transfer equipment.

In the real world connections without transfer switches are made all the time. A permit is not pulled and so there is no inspection. The homeowner or his friend just makes a connection to the panel and the turn off the main.

 

[yesterlectric]

I would never consider this being permitted for a dwelling unit, even with a locked room.

An connection at a dwelling unit requires some type of transfer equipment. Most AHJs accept the commonly available breaker interlock kits as being suitable for use a transfer equipment.

In the real world connections without transfer switches are made all the time. A permit is not pulled and so there is no inspection. The homeowner or his friend just makes a connection to the panel and the turn off the main.

I was dealing with a scenario not in a dwelling unit but where it would be correct to say that only qualified persons have access to the installation. I just made an extreme example to suggest a point.

A designer wanted to use 2 disconnects with an added interlock. However the code requires "transfer equipment" as opposed to adding an interlock. Furthermore, 702.5C requires that "transfer equipment" be listed, designed, and installed so as to prevent inadvertent interconnection. So unless a manufacturer has listed the modifications for the specific purpose of preventing inadvertent interconnection (doubtful they would list such a field modification because they may not know 100% what someone is doing in the field) one can't really say that adding the manufacturer provided interlocks to the 2 disconnects consists of a system that is LISTED to prevent inadvertent interconnection, despite that it may have been designed and installed for that purpose.

With this, it would seem that either:
1. The exception to 702.5A was simply put there so that anyone who would dare check would find that it is indeed legal for them to connect a generator in an unexpected contingency event if there and it was not intended to allow for planning for a provision for a temporary generator ;
or:
2. The exception is intended to allow for permanent provisions to allow later connection of a temporary generator, without requiring a transfer switch; in installations where only qualified people access the installation.

 

[don_resqcapt19]

Transfer equipment is not defined in the NEC. It is totally up to the AHJ as far as accepting interlock kits as transfer equipment for an Article 702 installations.
This differs from Article 700 and 701 applications were the transfer equipment must be specifically listed for emergency or legally required standby installations..