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Posted By: Grover Holiday lilghting questions - 12/02/05 11:23 PM
I'm down to the wire, and just got some bad news....

We have 2 trees - 50' tall. Each tree has 5 strings of lights. Power comes to 2 GFI's cut into a plywood panel where a basement window used to be - each GFI fed by it's own 20A breaker - thru a mechanical timer.

Old way: 100' NM - conduit sleeve under a snowplowed emergency access driveway to the first tree; 150' NM same path to the second tree. NM terminated with plug on one end - duplex receptacle on the other - suspended above ground and wrapped in plastic. 5 cords to the duplex - multitaps - to feed the individual circuits. Yes - using NM as an extension cord, not anchored or supported.

Town Manager, not Code Enforcement Officer has stated no tree lighting ceremony this year because of electrical hazards.

Is there any code compliant way to do temporary holiday lighting?
Posted By: JoeTestingEngr Re: Holiday lilghting questions - 12/02/05 11:35 PM
Low voltage lighting solutions???
Joe
Posted By: e57 Re: Holiday lilghting questions - 12/03/05 01:12 AM
Quote
Old way: 100' NM - conduit sleeve under a snowplowed emergency access driveway to the first tree; 150' NM same path to the second tree. NM terminated with plug on one end - duplex receptacle on the other - suspended above ground and wrapped in plastic. 5 cords to the duplex - multitaps - to feed the individual circuits. Yes - using NM as an extension cord, not anchored or supported.
Electrical hazards - No wonder. Maybe perminantly install up-lights at each tree, and install appropriate colored lenses for the holidays, thats what I plan to do with my front yard soon... For tree lighting, hang a bunch of white tags in the tree, the colored lenses will make them shine in color. Or laser show from a any distance.... Or, properly install outlets at each tree, with in use covers and have enough of them to not use tap plugs...
Posted By: ShockMe77 Re: Holiday lilghting questions - 12/03/05 01:42 AM
Being that you need these lights NOW not a month from now: shovels, rigid nonmetallic conduit, fittings, glue, FS boxes, GFCI's some thwn, tape, and a few in-use bubble covers should get the job done in code compliant fashion. I suppose you could also use some UF to get it done faster but be sure to checkout NEC article 340 before you do anything. Good luck.
Posted By: DougW Re: Holiday lilghting questions - 12/03/05 01:43 AM
If you can, I'd arrange for a section of RMC/RNC to be laid under the driveway as a chase. Then just use a 10/3 extension cord in lieu of the romex - maybe one of the "contractor cords" with a triple receptacle(factory) or j-box on the end.
Posted By: renosteinke Re: Holiday lilghting questions - 12/03/05 01:51 AM
A customer had me re-do their set-up. This was for a tree that approached 80 ft. in height.
I ran EMT along the building, under the eave. At the appropriate place, I dropped down to a very small load center. Attached to the load center is a "can" with a contactor, timer, and photocell. From the load center, I ran PVC pipe 2 ft. underground to the tree.
In the shrubbery around the tree, and near the trunk, I came up with some tape-wrapped rigid to some "Bell" boxes. These had GFI receptacles in them.

A lighting company did the tree itself; all they had to do was plug in.
Posted By: Grover Re: Holiday lilghting questions - 12/03/05 12:59 PM
Thanks for all the input guys!

Is the use of NM as an "extension cord" prohibited by NEC or OSHA? what about using UF as an "extension cord"? Code reference?

The town tree lighting is tomorrow at 4:45 PM!

My town is still using the 1999 code....
Posted By: iwire Re: Holiday lilghting questions - 12/03/05 03:54 PM
Considering your time frame I suggest the use of 10 AWG extra hard usage rubber cord.
Posted By: renosteinke Re: Holiday lilghting questions - 12/03/05 04:30 PM
Grover, the code simply says you need to use approved materiels. So- where you need flexable cord, you need to use "flexible cord,: examples of which are SO, SJO. SJTO, SEEOW, etc.
So the use of NM or UF would generally be considered a violation. The one "exception" being if the install is permanent, and the cord is buried. "S" type cords will not stand up to direct burial, and will rot through rather quickly.
OSHA does like to cite when NM is used as an extension cord. I say this, as this is one of the things that they specifically illustrate on their web site as a violation.

There seems to be a preferance at your site to using NM. I suggest that you look at this more closely...I doubt that any money was saved over 'doing it right.' To those in the trade, this sort of thing screams "amateur at work here."
Posted By: n1ist Re: Holiday lilghting questions - 12/04/05 12:57 AM
NM outdoors? Also, most plugs aren't rated for solid wire.
Posted By: Grover Re: Holiday lilghting questions - 12/05/05 11:23 AM
Well, it's done...

I hate these threads that never conclude, so I'll wrap this one up.

I got an agreement from the Town Manager that the town would bury wire (in the spring), so I ran #12 UF (load is 14.5A - voltage drop will extend bulb life <grin> )to each of the trees - 2 gang box with 2 duplex receptacles at each tree - plug on the other end - inside the building. When the trench is open, I'll stub up with PCV and a 90 at each tree, and stub up with an LB at the building, and hardwire to the mechanical timer.

Trees lit up on cue with a light snowfall providing a backdrop, kids had a great time caroling, doing crafts, and seeing Santa. Great fun for about 60 kids and parents in our little town out here in the woods of Maine.

Thanks to all for your input.

Grov
Posted By: Grover Re: Holiday lilghting questions - 12/05/05 11:25 AM
BTW, 12/2 UF is $65/250' here in Maine now!
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