Bell transformer at outdoor subpanel

[Unregistered]

How might one go about connecting a doorbell transformer to an outdoor subpanel?
I know the transformer should not be put inside the panel, since code does not allow low voltage devices in line voltage panels. Could the transformer be attached to a single gang waterproof box (mounted next to the panel and connected through conduit) and then covered with a bubble cover? Or should the transformer be better protected from the elements by being fully enclosed, e.g. in a junction box, and if so, how could this be done without violating the same rule that doesn't allow the transformer inside the panel? By the way, I'm trying to stay away from having to use a large, more expensive outdoor lighting transformer in a NEMA 3R enclosure.

[Wgoodrich]

They make outdoor weatherproof bells and transformers as on unit. Then all you have to do is power it and run you control circuit.

You could build a little building creating a weather resistant structure to install you transformer.

There are outdoor transformers listed for the use that are small compact and inexpensive. Just contact an electrical wholesale supply store. They may have to order one for you but they usually come in quickly.

Hope this helps

Wg

[Unregistered]

There are outdoor transformers listed for the use that are small compact and inexpensive. Just contact an electrical wholesale supply store. They may have to order one for you but they usually come in quickly.

Wg


I've done extensive web searching and I visited two electrical distributors, one which claims to be the biggest in the state (CT), but have come up empty. I did find some transformers that are mounted in their own, self-contained weatherproof metal boxes, but they aren't compact or inexpensive, and the current capacities are much more than needed for two doorbells.
Could you give the name of any specific manufacturer?

Now a code related question. I don't have a code book handy. I was wondering what the specific rule is that prohibits low voltage devices in line voltage boxes. Does this apply only to breaker panels? I can think of lots of equipment with high and low voltage in close proximity.

CLM

[joed]

I think the code prohibits low voltage rated wire not specifically low voltage. If the wire has a insulation rating the same or higher than the high voltage wire rating then I think they can be in the same box.

[mdshunk]

Could you give the name of any specific manufacturer?




Acme Transformer is a very popular maker of small, NEMA 3 rated (outdoor) transformers. I was nosing through their catalog just now... they have what you need, and nearly every electrical supplier I've ever delt with handles Acme (Acmepowerdist.com)

You can also get a regular transformer of the size you need from Square D, Cutler Hammer, Seimens, Allen-Bradley, etc., and get the accessory NEMA 3 mounting can for the transformer.

Mounting the doorbell transformer outside isn't quite "normal". Isn't there a light fixture box in the attic, basement, or utility room that you can hang a regular transformer on?

[Wgoodrich]

I believe the rule is being misunderstood. First a transformer is not allowed to be mounted inside a box unless manufactured that way and listed and labled as manufactured that way. Way back when we put transformers inside panels. Too many overheated transformers causing fires created the rule no transformers inside electrical boxes.

Second a class 2 wiring as you discribe is only allowed in a box with 50 volts or higher unless the box is listed for this use with a built in divider separating the class 2 wiring from those conductors 50 volts or more.

Two rules apply.

Hope this helps

Wg