Code Implications of Placing Portable Generator in DIY Enclosure

[bsf]

The portable generator enclosure is essentially a raintight box with front opening door(s); hinged roof; and ~1300cfm fan for positive pressure ventilation. A thermal switch (??F) grounds ignition spark in case of enclosure overtemp condition. An access port in the enclosure back wall allows a cordset to be routed between a raintight, power inlet box on the house and the generator. A mechanical interlock (QOCGK2) is used at the main panel for manual transfer.

I am trying to determine if placing the portable generator in the enclosure has any code implications.

These are specific questions I have.

• Is the enclosure considered “equipment” (702.4 Equipment Approval)?
• Is the generator still considered “portable” (702.7 Signals Exception & 702.10 Portable Generator Grounding)?
• Regardless of whether the enclosure is locked, for purposes of 445.18 Disconnecting Means Required for Generators, would you consider the driving means for to generator as able to be readily shut down?
• Anything else I am missing in relation to an “unlisted” DIY enclosure?

 

[ceb58]

The portable generator enclosure is essentially a raintight box with front opening door(s); hinged roof; and ~1300cfm fan for positive pressure ventilation. A thermal switch (??F) grounds ignition spark in case of enclosure overtemp condition. An access port in the enclosure back wall allows a cordset to be routed between a raintight, power inlet box on the house and the generator. A mechanical interlock (QOCGK2) is used at the main panel for manual transfer.

I am trying to determine if placing the portable generator in the enclosure has any code implications.

These are specific questions I have.

• Is the enclosure considered ?equipment? (702.4 Equipment Approval)?
• Is the generator still considered ?portable? (702.7 Signals Exception & 702.10 Portable Generator Grounding)?
• Regardless of whether the enclosure is locked, for purposes of 445.18 Disconnecting Means Required for Generators, would you consider the driving means for to generator as able to be readily shut down?
• Anything else I am missing in relation to an ?unlisted? DIY enclosure?

I would go with 100.3 B. What dose the mfg. instructions say about placing the gen. in an enclosure. Even with ventilation I think you would still be asking for trouble

 

[chris kennedy]

I would go with 100.3 B. What dose the mfg. instructions say about placing the gen. in an enclosure. Even with ventilation I think you would still be asking for trouble

I agree 100% with Curtis here, although his typo meant 110.3(B).

 

[cadpoint]

I would go with 100.3 B. What dose the mfg. instructions say about placing the gen. in an enclosure. Even with ventilation I think you would still be asking for trouble

Hold on! This is Michigan, they seem to have made provisions for putting it into this little structure... they didn't call it that, but that's what it is, (seems they are protecting their investment). It's hard to argue they didn't understand or skirt next to the rules,I totally understand this! I will give anyone that! Let's go and say that it's a seperate structure first, and seems to be isolated from other things? Yes no OK I get it, I'm just say'n it's MS...

 

[LarryFine]

Like this?:

 

[bsf]

From the Owner’s Manual

Safety Rules……………..

11. Units should never be operated under these conditions:………
i. In an enclosed compartment…….

14. The unit should be operated, serviced, and refueled under the following conditions:
a. Good ventilation – avoid areas where vapors may be trapped, e.g. pits, basements, cellars, excavations, boat bilges, etc. – air flow and temperatures are importand for air cooled units – temperatured should not exceed 100 F………………

Like this?:

Well sort of: larger, with more empty space, a fan, and the high temp cutout.

eta
Envision this, except made from plywood, dimensional lumber, louvers, and such.

http://www.nooutage.com/powershelterkitii.htm

 

[LarryFine]

Envision this, except made from plywood, dimensional lumber, louvers, and such.

That's how I made that one. PT plywood, framing, and slats. And, a big helping of Simpson StrongTie hardware.

The front panel hinges downward, and the owner put a hefty chain through a big eye-bolt he put in concrete.

 

[electricmanscott]

I don't see any way the NEC can apply to where somebody puts a portable generator nor do I think it should.

 

[ceb58]

I agree 100% with Curtis here, although his typo meant 110.3(B).

Thanks Chris

I don't see any way the NEC can apply to where somebody puts a portable generator nor do I think it should.

Very true. But in a round about way 110.3 B would be part of the total install. The mfg. instructions state not to put it in an enclosure so you would have a violation when you connected the premise wireing to the gen.

 

[chris kennedy]

The mfg. instructions state not to put it in an enclosure so you would have a violation when you connected the premise wireing to the gen.

It has to be able to breath as per installation instructions.

 

[brian john]

It has to be able to breath as per installation instructions.

And that can be calculated and allowed for in the design. Have you seen those CHEAP, LOUSY, TIGHT, neve go back together after opening enclosures the manufactures sell, can't be much worst.

 

[electricmanscott]

Very true. But in a round about way 110.3 B would be part of the total install. The mfg. instructions state not to put it in an enclosure so you would have a violation when you connected the premise wireing to the gen.

It is "portable" generator. It would not have premise wire connected to it. If it did it would no longer be portable and then maybe a different story.

 

[ceb58]

It is "portable" generator. It would not have premise wire connected to it. If it did it would no longer be portable and then maybe a different story.

An access port in the enclosure back wall allows a cordset to be routed between a raintight, power inlet box on the house and the generator. A mechanical interlock (QOCGK2) is used at the main panel for manual transfer.

Judging from the OP's scenario I think you could consider it as a permanent install. I have a portable gen. that I keep in my work trailer to use if needed on jobs, take it out move it around it's portable. If I need it at home during a storm or what ever I bring it out use it and put it back. It is not in an enclosure primarily for one purpose. I say that in this application it would be connected to the premise wireing

 

[jwelectric]

The portable generator enclosure is essentially a raintight box with front opening door(s); hinged roof; and ~1300cfm fan for positive pressure ventilation. A thermal switch (??F) grounds ignition spark in case of enclosure overtemp condition. An access port in the enclosure back wall allows a

cordset to be routed between a raintight, power inlet box on the house and the generator.

Would this be a problem with 400?

 

[bsf]

Would this be a problem with 400?

ARTICLE 400 ? FLEXIBLE CORDS AND CABLES

400.7 Uses Permitted.

(A) Uses. Flexible cords and cables shall be used only for the following:

1. Pendants
2. Wiring luminaries
3. Connection of portable luminaires, portable and mobile signs, or appliances
4. Wiring of cranes and hoists
5. Connection of utilization equipment to facilitate frequent interchange
6. Prevention of transmission of noise or vibration
7. Appliances where the fastening means and mechanical connections are specifically designed to permit ready removal for maintenance and repair, and the appliance is intended or identified for flexible cord connection
8. Connection of moving parts
9. Where specifically permitted elsewhere in this Code

400.8 Uses Not Permitted. Unless specifically permitted in 400.7, flexible cords and cables shall not be used for the following:

1. ??
2. Where run through holes in walls, structural ceilings, suspended ceilings, dropped ceilings, or floors
3. ??

Maybe. Possibly. Probably.