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TANGOMAN
01-02-2003, 03:07 PM
I'm in the process of building some "temporary" light hoods for 4' Actinics on my 90g. I'm just using a standard resistance type ballast. I've got materials for DIY waterproof end-caps and I'm unsure of what gauge of wire I require. I've got "Coralife" end-caps on my 60g and it's very light/flexible wire. Maybe 18 gauge or higher ? Does anyone know what the voltage is at the bulb connector on a 40W ballast ? Is it still 120V or is it dropped ? The wiring and end-caps are later going to be installed in a canopy when I get around to building one...
I really don't want to make a fire insurance claim :wink:
FYI, I bought a 10' length of vinyl eavestrough/end caps, cut two lengths and primed/painted and they look pretty damn good...that's important because there's nothing worse than hearing "you're not leaving it like that in the living room are you ?" :evil:

Delphinus
01-02-2003, 04:16 PM
I used 18g on my DIY fluorescents on my 50g. It was a chore to find solid core instead of stranded in that small a size.

Anyways, what I used, turned out to be inappropriate for the fluorescent sockets. I don't know if it was the heat produced by carrying the amount of current that they were, or if it was the heat from the lamps itself. What happened was the insulation became brittle, and eroded away in places leaving exposed wire. One day, I thought I heard an odd noise so I started looking at all my wiring, and in an obscure spot, I found a spot where there was arcing across two wires (plus little puffs of smoke).

Anyways, so I guess my point is, whatever guage you use, check the rating for the insulation. I think that the wires used in typical 40W ballasts is 18g, so 18g ought to be OK. The problem going to a larger wire size is that you need a fairly slim wire to slip into those typical fluorescent sockets, but obviously going to too thin a wire causes worse problems.

Canadian Man
01-02-2003, 06:12 PM
I can't give anymore advice than Tony gave, other than tellling you I am using the wire that comes on the ballast's for all my florescents

Tau2301
01-02-2003, 10:15 PM
I am using 14ga wire as my ballasts are about six feet away from lamps. Plus being overdriven I thought a larger gauge wire would be best.

reefburnaby
01-02-2003, 10:48 PM
Hi,

Technically, the electrical code states that the wiring between the lamps and the ballast are suppose to be rated at 600V and rated for a operating temperature greather than 90C. The wires that come attached to your ballast are suppose to be rated for those conditions.

The operating voltage across a 4 foot T12 is around 100V. At starting, the voltage can jump as high as ~200V. So, wiring rated at ~240V or so is fine. You can derate the operating voltage requirement to ~300V for this application, but the temperature requirement may more difficult.

Something like regular house hold wiring or zip cord is not good enough. Something like heavy duty wiring for outside extension cable is not quite up to code, but it is okay. This type of wire is called cabtire and the usual temperature rating is around 60C. If you can keep the temperature below 60C, then it should be fine. One of the other reasons why wires breakdown is because of UV radiation. I would not use this type of wiring in MH.

The electrical current passing through the lamp is usually less than 1 amp (probably around 430mA) for a normal T12, so a 18 AWG is fine.


- Victor.

StirCrazy
01-02-2003, 11:55 PM
Or you can just go to home depot and get solid core 18ga wire.. they have it in different colors and it is cheep.. and that is what is atached to the ballast.

Steve

Delphinus
01-03-2003, 06:07 AM
I found the only solid core 18guage wire my local Home Depot had was the three-wire stuff to run between your doorbell and your furnace (carries only, what is it, 14V?) ??? I wasn't sure if that stuff was safe to use or not. The only other stuff that they had in 18guage was stranded.

(Alls I know is, electricity hurts when you touch something you shouldn't...)

StirCrazy
01-03-2003, 06:16 AM
Toney, they should have it as seperat stran in bulk.. just ask for wire for floressent fixtures.. thats what I did.. the first time I got 14ga wire but it is to big and it is hard to make fit in the endcaps properly.. it does work just a little harder to work with.

Steve

Delphinus
01-03-2003, 06:22 AM
Yeah, I've done 14 guage wires on my plant stands, but I've also wrecked a few sockets that way too unfortunately.

Hmmmm. Well, next time I will ask for that and see what they say. Thanks for the tip.

Bob I
01-03-2003, 10:58 PM
Just an idea. You can probably get all the 18 gauge wire you want at Radio Shack, or other electronic supply places. You do want wire capable of withstanding 90 degrees C. That is a Canadian electrical Code requirement. We used to use fixture wire, it was rated at 110 degrees I believe, but it was stranded. Anything with X-Link insulation is good for 90 degrees.

StirCrazy
01-03-2003, 11:08 PM
Bob, serious question here.. what does the electrical code say for wire between the ballast and the bulb of a 250 watt Pulse start MH.. inside a tank hood.. I know it has to be rated for 600volts but what is the smallest I can get away with assuming a 5 amp max current (in a short circut) but a normal current under 3 amps..

Steve

Delphinus
01-03-2003, 11:27 PM
This was electronic wiring that I used, that had had the insulation issue, and although I don't recall the exact rating, it was (I'm pretty sure) over 100 deg C, which is why I thought it would be OK.

But maybe the issue wasn't heat, but UV exposure. I don't really know. What can we do to minimize these kind of issues, use some kind of conduit maybe (PVC conduit or maybe the rubber slip-on type of wiring caddy's?)

reefburnaby
01-04-2003, 07:15 AM
Delp,

For UV protection, I believe the wires that have darker insulation colour (say black) will stand up better than white - even if they are made from the same material (its a physics thing). There are cables that can withstand more UV than others and they are usually categorized for external or outside use. I believe hookup wire from from Radio Shack isn't design for outside use.

If you want good protection from UV, good protection from the elements and fair good temperature resistants, Cabtire is a good choice. Another method of protecting the wire is to use electrical conduit (one form of it is in Gray PVC in the electrical section). These conduits are usually used to protect wires from the elements and from external damage (like a crazy forklift driver). You can use the white PVC as a conduit, but it isn't quite up to code. Another cable that is good is TECK cable (but it is a little extreme).

Hope that helps.

- Victor.

Delphinus
01-04-2003, 08:54 PM
Thanks Victor.

On a point of interest, the wiring I used had purple (almost "lavender") coloured insulation. It was just normal output, non-overdriven 40W fluorescent lighting.

Canadian Man
01-04-2003, 09:09 PM
One thought Tony is that you didnt have any Reflectors on that 50gish tank when you had the actinic on it. Correct?
Would this have anything to do with not focusing the light downward, away from the wire instead of all directions, so more toward the wire?

Bob I
01-05-2003, 04:47 PM
Bob, serious question here.. what does the electrical code say for wire between the ballast and the bulb of a 250 watt Pulse start MH.. inside a tank hood.. I know it has to be rated for 600volts but what is the smallest I can get away with assuming a 5 amp max current (in a short circut) but a normal current under 3 amps..

Steve

I am sure the code does not address that question directly, but I have a feeling you could get away with #18, But it is a guess. :?