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Hobby Assistance, please...
2

Hobby Assistance, please...

Hobby Assistance, please...

(OP)
I've decided to add electric lampmaking to my list of hobbies.

Problem: the books on electric lampmaking rarely  discuss wiring, and if they do, tying an underwriter's knot is the most detail given.

I have two lights, they're your typical, inexpensive, off-the-shelf lamps and I'd like to wire them to a single switch. The lamps are rated for a maximum of 150 W each (most likely I'll use a lower wattage bulb in each, probably a 60 W flood or spot). I live in New York, USA, the circuit in my home on which the lamps will be attached is 20A/115V AC.

So far what I've done is:

1. Cut the plug off both lamps.
2. Connected the wire from each lamp to a 20-ft length of 18/2 lamp cord. (The lamps also were 18/2). The connection is contained within a Radio Shack plastic enclosure and the wires are connected by non-soldered terminals I also bought at Rddio Shack. The hot and cold wires are spearated from each other by about .5" and they're tied down to the enclosure using plastic clips I bought at Radio Shack. (I'm not advertising for Radio Shack, but...) Prior to attaching any switching to the 20-ft cord, I tested the connection by attaching a plug (that I bought at Home Depot) to its end and plugging it in. The lamps functioned normally and I didn't detect any heat (a concern?) coming from the plastic enclosure after five minutes.

What I am exploring doing is adding an on/off switch to the 20-ft cord. I want to add a rocker switch (with enclosure) to the cord, the purpose of which is that I want to fix the switch to the side of a bookcase, rather than having the cord hang. Radio Shack sells a maintained rocker switch that's rated at 6A/125V AC. In order to attach this switch, I would cut the 20-ft cord at the appropriate length and wire it to the switch, hot-hot, cold-cold. I would then place the switch in another plastic enclosure that would be fixed to the bookcase.

Thoughts/Questions/Suggestions?

Thanks very much in advance!

RE: Hobby Assistance, please...

hi dave
  I'm not in the US so I can't comment on cable sizes over there. I will point out if you put 2 globes on (in parrellel) then you will double the current flow so the cable size may need to be upped to allow for this.

Where you run the cable into and out of boxes etc then clamp them so they cannot be pulled out.
again where you run the cables into and out of boxes make sure they are bushed or grommetted so the insulation does not fray with time.

I would suggest that if you hunt around the bookstalls and libraries you will find some quides to wiring. I have a couple of handy man books here from the US I picked up for the carpentry with US based electrics.

In the electronics hobby mags down under if they have a mains powered kit then there is usually a section on the safe wiring etc. Have a browse at your local newsagent.
try "popular mechanics"

When you strip a wire do not cut back or nick any of the copper conductors and strip absolutely no more insulation than the terminal hole it is to go in. A part of the trade prac. exam here will fail you if the instructor can see exposed copper.
 
For safety might I suggest you do what I am doing with my christmas lights. Where I am after a spot light then I am using those 12v ac dicroic lamps (downlights). They come in a variety of sizes etc and the transformers come with plug and lead already wired. You can have some fun with these.


now I've given a few suggestions here but here is the disclaimer : I am a long way from the US I don't know exactly what you are doing so I can't be responsible if I'm mistaken. please be careful and verify every thing with a local expert.

If I think of any more suggestions I will post them.

Regards
Don

RE: Hobby Assistance, please...

Hi,

This is probably way to late but just happened to come across this site & thought of you & your question

See:-
http://doityourself.com/electric/index.htm

For all things diy electric

Any help ?, yes no let me know.

Regards

RE: Hobby Assistance, please...

Suggestion:
1. The lighting circuit should be protected by 15A protective device (fuse or circuit breaker) and run as big as possible conductors up to number 14AWG for the safety reasons. Also, the National Electrical Code (NEC), NFPA 70 - 1999 and now 2002 edition is highly recommended to follow. The hot wire is necessary to interrupt by the switch if the receptacle and cap are appropritely configured, else, it is better to interrupt both conductors leading to your lamp. The wiring shall not be made permanent (or fixed), if it consists of cords.  This is considered unsafe by the NEC. Proper permanent wiring consist of appropriate installation for permanent purposes, which may consist of ROMEX concealed or BX exposed cables, for example.

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