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mark petty
02-08-2016, 10:21 AM
Aluminum screen enclosure frame at rear patio with aluminum panel roof - no pool - ceiling fans attached to aluminum beams - wire connections (wire nuts) visible above decorative fan housing cover - cables routed through aluminum beams through rough cut openings w/o protective bushings - no visible ground rod or bonding. Other than adding protective bushings; shouldn't the enclosure be boned or grounded. Forgot to take photo of fans. Thanks

Gunnar Alquist
02-08-2016, 11:41 AM
Aluminum screen enclosure frame at rear patio with aluminum panel roof - no pool - ceiling fans attached to aluminum beams - wire connections (wire nuts) visible above decorative fan housing cover - cables routed through aluminum beams through rough cut openings w/o protective bushings - no visible ground rod or bonding. Other than adding protective bushings; shouldn't the enclosure be boned or grounded. Forgot to take photo of fans. Thanks

Mark,

Looks like individual conductors rather than NM. Unless the channels are approved as a raceway, MC or conduit should have been used. Is that considered a dry area or damp area? If damp, then NM is not allowed (seems to me water could condense on the metal, making it damp/wet). If dry, then MC should be ok.

Junction boxes would have been required at the fans.

Given that you are in Florida, I believe bonding of metal buildings to protect against lightening strikes is required.

Best bet in my opinion, note what you see, state your concerns and recommend corrections by a licensed electrical contractor.

mark petty
02-08-2016, 01:06 PM
Gunnar, thanks for your help, I'll do just that

Dom D'Agostino
02-08-2016, 02:08 PM
Looks like NM from here.
Should still use ordinary installation methods to protect the cable.

Dom.

Jerry Peck
02-08-2016, 03:29 PM
250.4(A)(2), (3), (4), and (5) can be applied as they address things such as 'Normally non-current-carrying conductive material enclosing electrical conductors' and 'electrically conductive material likely to become energized'.

Those NEC code section can be applied to screen enclosure which have lights, receptacles, ceiling fans, wiring installed on the metal screen enclosure frame or run through it to require ground and/or bonding (depending on the applicable code section used).

Not for the purpose of lightning, but for the purpose of being able to clear a ground-fault, (5) in the code above, for the circuit which could energize it.

Additionally, your description indicated no junction box was present, the screen enclosure frame was being used as a non-listed raceway for the NM cable, is the screen enclosure designed to carry the active weight of the ceiling fan, is the screen enclosure a listed ceiling fan mounting, not protective bushings where the NM cable enters the screen enclosure frame ... just to name a few things which come to mind right away.

Gunnar Alquist
02-08-2016, 07:12 PM
Not for the purpose of lightning, but for the purpose of being able to clear a ground-fault, (5) in the code above, for the circuit which could energize it.


Jerry,

I thought there was a requirement for bonding metal buildings and other metal systems (gutters, etc.) in areas where lightning strikes were possible.

Jerry Peck
02-08-2016, 07:26 PM
Jerry,

I thought there was a requirement for bonding metal buildings and other metal systems (gutters, etc.) in areas were lightning strikes were possible.

Gunnar,

There is not, to my knowledge, a requirement to bond metal buildings or frames to ground or to the grounding electrode system ... it is permissible to do to, and when done, it must be done as the code states.

I am attending a half-day Lightning Protection Systems seminar Wednesday, it's been on my schedule for about a month and a half, I should be able to provide additional information then if there is a requirement for it.

I started to do a newsletter on Lightning Protection Systems and could not find much in the codes about them, I've had the NFPA 780 standard for the 'Installation of Lighting Protection Systems' and the UL 96A standard for 'Installation Requirements for Lightning Protection Systems' on my desk for a couple of months now trying to find out more information on them and how/what the code require.

Hopefully, Wednesday's seminar will provide additional information on them and code requirements.

From what I have found so far, a lightning protection system is not required to be listed, but if listed, then it would need to be installed in accordance with its listing (such as the UL 96A standard).

There is a third standard, it is from the Lightning Protection Institute, but it not mandatory either, and is not a 'third party' standard, it is their own 'industry standard' created by and for the industry.

Gunnar Alquist
02-08-2016, 10:59 PM
Thanks Jerry. Not sure where I got my erroneous information. Probably made it up in my head. :cool:

Bill Bryan
02-10-2016, 07:06 AM
I used to have a map on my wall showing areas where lightning was NOT possible. Now I can't find it!:p

Jerry Peck
02-10-2016, 09:43 AM
I used to have a map on my wall showing areas where lightning was NOT possible. Now I can't find it!:p

Is it that blank paper you just put in the printer? :)

Jim Port
02-10-2016, 06:31 PM
I would consider the framing member not as a raceway, but as a sleeve since a Chapter 3 wiring method was used. AFAIK sleeves are not required to be listed. I agree that bushings or some other means of protection is needed against the sharp edges of the framing. I believe the framing is made to accommodate wiring internal to the panels or framing.

Jerry Peck
02-10-2016, 07:48 PM
Hopefully, Wednesday's seminar will provide additional information on them and code requirements.

Not any substantive changes to my previous information as a result of the class I attended today.

- - - Updated - - -


I would consider the framing member not as a raceway, but as a sleeve since a Chapter 3 wiring method was used. AFAIK sleeves are not required to be listed.

Define "sleeves" being as you are saying that they are not "raceways".


I believe the framing is made to accommodate wiring internal to the panels or framing.

I have not seen any information which allows, permits, or even indicates that the aluminum posts and beams are suitable for using to run electrical in them.

Think of post light standards, they are suitable for that purpose and are listed for that purpose.

jack davenport
02-14-2016, 07:02 AM
Looks like that "NM" is actually UF cable ran through that channel. Why would it be illegal to run through the channel? I'm not talking about the missing bushing, or electrical fan box, but using the channel to route the cable to the fan. The only thing that I can think of would be the structural integrity of the channel & was it designed/engineered to have holes drilled into it.