wiring question, take 2

[kevin]

This conversation seems to be spiraling down hill.

#1. Don't listen to the home depot guys. Some times you can get lucky (the Home Depot paint girl here is very knowledgeable, for example), but more often than not you get know nothings. [ As an aside, my brother gave a nice explanation after working for a few years in a department about which he knew nothing: if a customer asks a Home Depot employee ANYTHING, then the customer is obviously even more clueless than the employee, so the employee might as well just make something up

-- don't want to seem ignorant, after all -- since the customer would't know the difference anyway. ]

#2. Don't listen to people who are "guessing" and "wondering", and who don't think twice about advocating doing things that "aren't completely kosher".

#3. Usenet can be helpful sometimes. Look for the consensus answer from people that seem cautious, reasonable, and knowledgeable. The consensus here (which I would agree with), is to install a switched receptacle, put a plug on the lamp cord, then just plug them in. Many under-counter lights these days are designed for exactly this case. I just installed some a few weeks ago, and this was exactly the manufactures instructions -- it even came with the plug for the cord, which could be cut to length. If you can put the outlet somewhere reasonable, it looks fine. For example, my (already existing) outlets where right up underneath the cabinets anyway, so you can't see the cord at all. I just had to rewire (half) the outlet to make it switched.

And, lastly, since no one else has mentioned it yet -- a 20A circuit requires 12 guage wire, not 14ga, to the receptacle.

[Doug Miller]

You've got lamp cord. Fixture wires are the ones that come already attached to a light fixture, by the manufacturer.

-- Regards, Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt. And who wants to leave buttprints in the sands of time?

[JK]

[noemail]

If he is to install an receptacle, he might just buy a few feet of 12/2 and join with the under-counter fixture wire in the fixture box. He does need to get the fixture that was for hardwiring instead of pluging in. Cost of plug-in and hardwire type undercounter lights are about the same.

[noemail]

If you place the light close to wall, there is no romex exposed. Romex can enter the fixture junction box from top or back of the fixture by punch out a hole. Since his wire comes from wall, you punch back. There is also a connector with a clamp on your fixture to protect the romex from moving.

[Doug Miller]

NO.

You don't understand things well enough to be doing this yourself. A transformer is used to power low-voltage equipment. You said that what you have is 120V.

-- Regards, Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt. And who wants to leave buttprints in the sands of time?

[Andy Hill]

[Chris Lewis]

According to JK :

The HD guy is just plain wrong. There aren't any circumstances where code permits you to hard wire 18ga (lamp/appliance) cord into a 120V circuit.

Like, where's the ground wire?

The wire is not rated for covering in walls or installing in boxes.

This is basic wiring rules.

On a 20A circuit, it'd melt and/or catch fire if there's a fault.

[Yes, some hard wire fixtures have internal wiring smaller than 12 or 14ga, yes, appliance cord is often smaller than 12 or 14ga, but these devices have been approved by the appropriate agencies specifically for _those_ situations. Hardwiring lamp or appliance cords into a 15 or 20A 120V circuit is _not_ one of these purposes.]

Install a receptacle with regular house wire, and plug the halogens into it.

[luv2cmwork]

Bad advice? Maybe. I'm admittedly, not an expert. And apparently, not as egotistical as yourself either.

It occurs to me, that I have many lamps in my house, that are plugged into outlets with 14 gauge (or higher) wire. In fact, much of the lighting I've seen, including halogen recessed lights, has 18 gauge wire coming from the fixture. By connecting those to 14 gauge wire, is the risk of fire any less than using the fixture wire to a switch as in my application? And if so, why?

In other words, if you plug an 18 gauge wire, with a plug (as you suggest) into a outlet wired with 14 gauge wire, why is the risk of fire any less? I can see why you wouldn't want it going into a junction box, because you wouldn't want to use that wire for anything other than it's intended load. But I fail to see the problem with going into a switch?

I could very well have some flawed logic here. It probably isn't the right way to do it, but why is it less safe? As long as I don't try to put any more load on the fixture cord I fail to see why it's less safe?

And if you could answer that question, in 2 slams or less, I'd appreciate it.

[luv2cmwork]

OK, makes sense. I respectfully defer to experts such as yourself. And appreciate the tone of your remarks. Thank you. I know I'm wrong...I'll admit it. But like any good man who finds himself on the wrong end of an argument, I'll leaves with at least a few parting remarks.

inspection,

Free air, I can understand. But I have reservations about less frequent use. In fact, since in this application, it's attached to a switch and used a few hours a week at most, verses permanently plugged into a receptacle...seems to me wiring to a switch would be less frequent use. But I see your point entirely about visual inspection. That makes perfect sense.

(enclosed -

You're absolutely right. I've seen lamp cord deteriorate after time. Bends, clamping and the like can all contribute to it's early demise. However, if handled carefully, it seems (to me at least) the primary cause of deterioration comes from light or specifically, UV light, which of course, the wire would not be exposed to inwall. But in general, you are correct and I would agree.

It is dangerous, as you've eloquently pointed out. However, I would never use it as inwall wiring in general. This application is for a halogen, low wattage undercabinet light. The lights are UL listed which means the wire they came with, is certified to work with those lights, with an assumable margin of safety. I would never put any more load on it than the one intended and therefore, would find it unlikely that it could be overheat, even enclosed (at least in my application).

I was not aware of this. Good point. If the wire is in a wall where the heat could not dissapate (heavy insulation) I would worry. In my application, it was a inside wall, in a empty stud apace.

Agreed, as I said, I've seen it happen. However, it seems that I read or heard, that the majority of the deterioration comes from UV light. But you are absolutely right and I would agree.

Nor would the lights, as they are plugged into a receptacle. So no difference there....Correct?

I do appreciate your response. Now that you've pointed some things out, I see your point. My biggest concern, is the longevity of the wire insulation. Although the wire is not buried in wall insulation or subject to any other stresses (sharp bends or over clamping).

[Duane Bozarth]

[e-mail] wrote: ....

The key point is that you may well not be the final occupant of the house and would be leaving some other poor schmuck w/ a shoddy piece of work that would be totally unexpected... :(

[Chris Lewis]

According to :

An 18 or 16ga appliance cord is in free air, subject to visual inspection, less frequent use, and has been tested and approved for misbehaviour under those conditions (by UL or CSA or CE or...).

In contrast, permanently wiring is under different conditions (enclosed - less heat dissipation ability, sharp bends, clamped, not visible, and is expected to live almost indefinately). That wiring is in turn tested and approved for _those_ conditions (by UL or CSA or ....)

Installing appliance cord, particularly 18ga lamp cord, as generic inwall wiring is dangerous: it'll overheat on loads that won't trip a breaker and potentially cause fires. Yet, that same overload won't necessarily cause a problem in free air.

[Ie: 18ga wire, in free air, won't melt until you try to push 100A through it. Buried in insulation, 10A may well do it.]

The insulation usually has a lifetime much shorter than real house wiring, and will perish, crack and fall off. And you won't see the problem.

It doesn't have a ground. Etc.