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#187236 - 06/17/09 09:32 PM pendants
twh Offline
Member

Registered: 03/11/04
Posts: 892
Loc: Regina, Sask.
Rule 4-010(2) states "Flexible cord shall be permitted to be used for"... "(c) pendants".

"Pendant" isn't defined in Section 0, but in the dictionary it is defined as anything hanging. I've seen hanging lights (usually incandescent) wired in flexible cord and hanging receptacles. Some fluorescent fixtures come with a flexible cord whip and some come with SOW connectors.

I'm thinking that flexible cord is permitted for hanging fixtures, including fluorescent fixtures.

AC90, which is the way I've been wiring hanging fluorescent fixtures, has different rules. Rule 12-610 provides that AC90 shall be supported in accordance with Rule 12-510. It must be supported within 300mm of a box and every 1.5m through the run.

The AC90 is usually attached to the chain with tywraps. Tywraps are not an acceptable support. Nor is a chain a substantial structure for a support.

I can't wire a pendant (hanging) fixture with AC90 and meet code. It's allowed just because that's the way it's always been done. The same isn't true with flexible cord. The code actually permits using flexible cord to wire anything pendant.

Have I been doing this wrong? How are these issues dealt with in other areas?

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#187311 - 06/21/09 08:09 AM Re: pendants [Re: twh]
Eddy Current Offline
Member

Registered: 09/26/06
Posts: 112
Loc: Ontario,Canada
Pendant lampholders are covered in Sec. 30-608
When you hang a fluorescent fixture from a chain that doesn't make it a pendant, it's a suspended fixture.
Flexible cord is fine, some fixtures (even hi-bays) come with flexible cord already attached.
You can even use 14awg wire taps to each fixture on a 20amp circuit. 30-412
The only thing you have to worry about with flexible cord is mechanical protection and the weight of the light not placing tension on the connections 30-400 and 30-406

Quote:
The AC90 is usually attached to the chain with tywraps.

??? Round here tie-wire is used.

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#187312 - 06/21/09 08:48 AM Re: pendants [Re: Eddy Current]
twh Offline
Member

Registered: 03/11/04
Posts: 892
Loc: Regina, Sask.
Quote:
When you hang a fluorescent fixture from a chain that doesn't make it a pendant, it's a suspended fixture.
One type of fluorescent fixture has a spec sheet that says the fixture can be installed "pendant".

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#187314 - 06/21/09 11:52 AM Re: pendants [Re: twh]
Eddy Current Offline
Member

Registered: 09/26/06
Posts: 112
Loc: Ontario,Canada
Quote:
One type of fluorescent fixture has a spec sheet that says the fixture can be installed "pendant".


????? Odd, proably means to be installed by itself instead of together with another fixture? Where was the fixture made? Possibly a translation issue? Every plan I've ever looked at usually refers to a pendant as a single, hanging light.


Edited by Eddy Current (06/21/09 11:53 AM)

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#187316 - 06/21/09 01:18 PM Re: pendants [Re: Eddy Current]
twh Offline
Member

Registered: 03/11/04
Posts: 892
Loc: Regina, Sask.
The hanging controller for a travelling bridge crane is also called a pendant, as is a hanging explosion proof light.

I'm beginning to doubt that the only time flexible cord can be used is when it's installed by the factory. That has been the way the rules have been applied, here.

So, why can't I put the flexible cord on the fluorescent fixture? Is this rule only in Saskatchewan?

When I look at the code, I wonder why BX is allowed.

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#187382 - 06/24/09 09:06 PM Re: pendants [Re: twh]
jay8 Offline
Member

Registered: 07/28/05
Posts: 183
Loc: Vancouver, BC
Have you been told by your local authority that ty wraps are not acceptable to fasten BX? They are CSA approved, and would be preferred to tie wire which has no approval to fasten BX, conduit etc but does get used frequently for that.

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#187430 - 06/26/09 04:24 PM Re: pendants [Re: twh]
mikesh Offline
Member

Registered: 06/07/06
Posts: 614
Loc: Victoria, BC, Canada
I have been trying to find a reasonable answer to all of the questions but I am still thinking about a couple of things.
By impression a chain hung fluorescent fixture is not a pendant but a chain hung luminaire. They usually have 2 chains to hang from them, If the fixture was at the bottom of a single chain drop I might call it a pendant. Anything that swings or is meant to be movable should be wired with stranded conductors. I don't think BX is really legal for a chain hung fixture but a rod hung fixture would be ok. Never rejected a job for using bx to wire a chain hung fixture but maybe I should start.

Ty raps are approved for support of electrical wires and cables but the problem is the way they are approved. They don't list supporting BX or NMD or any cable type but are listed to support XX kilos and the environment they are approved for use like indoor/ outdoor, corrosive, halogen, petroleum, etc. in choosing a ty rap you have to estimate the weight it must support if installed as per a strap. You also have to apply an undefined safety factor and most inspectors just don't like to assume. Ty wire is not approved for support of any electrical device yet it is as common as anti-shorts. Ty wire has no rating for support of anything I know of but is definitely rated to attach 2 pieces of rebar to each other.
My supervisor regularly rejects the use of ty wire but I will tolerate it's use on BX inside of stud walls.
Flexible cords are definitely approved for wiring and suspended fixtures where it can move relative to the building. It must for the most part be rated for 90 degrees and in the case of some HID luminaires 105 degree wire is necessary.
Chain is rated for weight of the load and fluorescent fixtures can be purchase with chain hanging in mind. IE they have a saddle supplied. The links supporting the fixture cannot be cut so if you use jack chain be sure to cut the 1/2 link off the drop. Local seismic engineers have approved chain as a seismic support for tbar mounted fixtures too.

So what is a pendant? it is a single point drop with a single device at the end. Many pendants are supported by the cable with either an internal messenger in pendant cables or the simple 2 wire fixture wire woven through a suspension chain like a swag light.
It would likely be a single medium base socket with a shade or globe and a canopy at the ceiling outlet box.
A pendant can be a cord receptacle on the end of a piece of cabtire.

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#187438 - 06/26/09 07:33 PM Re: pendants [Re: mikesh]
twh Offline
Member

Registered: 03/11/04
Posts: 892
Loc: Regina, Sask.
Quote:
I don't think BX is really legal for a chain hung fixture
You're right. 30-406(1) specifies stranded conductors. I missed that.

As to the tywraps, I was told that they aren't allowed, and I accepted it without checking. I'm going to follow up on this. However, tywraps holding BX aren't the mark of a quality installation, anyway.

When I read the definitions of pendant on the internet, I see the single drop point definition. I'm not in favour of narrow definitions, but you have a good point. Unless I'm missing something, I don't think it changes anything, here.

Thanks for the education.

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#187482 - 06/27/09 11:27 PM Re: pendants [Re: twh]
jay8 Offline
Member

Registered: 07/28/05
Posts: 183
Loc: Vancouver, BC
twh, you raised a good question, sounds like a lot of installers have been taking things for granted regarding bx on chain hung luminaires which you see everywhere, and the proper application of ty wraps and the use of tie wire. Some good discussion generated from this.

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#187489 - 06/28/09 01:28 PM Re: pendants [Re: jay8]
bigpapa Offline
Member

Registered: 03/18/06
Posts: 75
Loc: canada
I find tie wire far superior to even the best quality tie wraps
for supporting bx to chain. I use mostly aircraft cable
for hanging fixtures and tie wraps simply don't work as well for this
and they are combustible.

Regarding the stranded wire issue, cables such as cab tire
may not conform to building codes as far as being combustible etc so
they are only tolerated in very short lengths in non combustible buildings.

Does anyone know if there is a flexible cable that is approved for this
application. I notice that fluorescent fixtures meant to be cable hung come with a piece of white cable that looks far better than an ugly piece of bx.



I think that movement of a hanging fixture is rare so solid wire is suitable
and trying to find a code rule that prohibits it is counter productive in real
practise but reasonable for discussion.
I hope there are no inspectors who would actually reject this practise.

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