Flexible Cable for Generator

[winnie]

It sounds like your customer is trying to reinvent the wheel.

You need to get power from a generator outside to building wiring inside, in a location where the outside air is corrosive. I presume salt spray, not sulfuric acid clouds, but if you are doing a design/build on Venus, I want in as a consultant.

My guess: the marine or offshore oil industry has off the shelf products that will do the job for less that 10x reasonable $$.

IMHO the prohibition against routing flexible cords through holes is to prevent its permanent installation in place of proper building wire, and the prohibition against going through doors or windows is to prevent its getting pinched or damaged when those openings are used for their normal use. IMHO a large enough opening specifically for the temporary passage of cords should be just fine. Sadly my opinion doesn't really match what the code actually says.

Jon

 

[don_resqcapt19]

I had reviewed Article 590 and 590.4(H). I don't think it is applicable.

590.3 Time Constraints.

A = During period of construction
B = 90 Days in reference to holiday lights
C = Emergency and Tests - I don't think a pre-planned generator inlet can be considered an emergency situation. There is a choice to be put outside and therefore not be in conflict with 400.12, it is chosen to be put inside, causing the issue. I see C being applicable where lets say a tree falls down on your incoming service equipment and you run a line to the input of the main panel. Not a pre-engineered roll up generator hookup scenario.
D = Removal, talks about that it needs to be removed immediately.

In my opinion the need to use the external generator is the "emergency" and would permit the interior connection box to be used. The cables will not be there unless you lost external power.
Note that the term "emergency" in this use does not mean the same thing as in Article 700. The term "emergency" is commonly applied to all sources of standby power.
I would have no issue with this from the AHJ viewpoint.

 

[zbang]

(What Don said)
A pre-installed inlet does not make an emergency situation any more than stockpiling food and water does; the hurricane (tornado, earthquake, truck-running-into-the-pole) makes the emergency.

 

[W@ttson]

It sounds like your customer is trying to reinvent the wheel.

You need to get power from a generator outside to building wiring inside, in a location where the outside air is corrosive. I presume salt spray, not sulfuric acid clouds, but if you are doing a design/build on Venus, I want in as a consultant.

My guess: the marine or offshore oil industry has off the shelf products that will do the job for less that 10x reasonable $$.

IMHO the prohibition against routing flexible cords through holes is to prevent its permanent installation in place of proper building wire, and the prohibition against going through doors or windows is to prevent its getting pinched or damaged when those openings are used for their normal use. IMHO a large enough opening specifically for the temporary passage of cords should be just fine. Sadly my opinion doesn't really match what the code actually says.

Jon

I agree with all of this.

It’s a common sense approach both ways.

One way, it should be pretty apparent that straightforward to just have the inlet installed outside. It’s a clean connection, no questions on NEC compliance.

On the other hand, even if on the inside, if the intent of that section is met, that is, the hole or opening or cable is protected in a way that doesn’t subject it to damage then it should be OK. Should be a 1-2-3 confirmation from an AHJ.

 

[W@ttson]

In my opinion the need to use the external generator is the "emergency" and would permit the interior connection box to be used. The cables will not be there unless you lost external power.
Note that the term "emergency" in this use does not mean the same thing as in Article 700. The term "emergency" is commonly applied to all sources of standby power.
I would have no issue with this from the AHJ viewpoint.

Certainly, this is all we would need. AHJ simply confirming acceptance. In the absence of the code being clearer we need a simple AHJ clarification/confirmation. The logic is reasonable and allowance per the AHJ would not be unusual.

As for the whole emergency vs non-emergency issue, I just don’t like that a piece of equipment can be designed and subsequently installed and it’s code compliance is predicated on whether or not something is designated an emergency. By choosing a different location no matter the situation, emergency or not, it will always be code complaint.