Dimmer for nightlight

I would like to use a smallish rotary switch that clicks on/off and then you rotate to adjust the brightness of a 120v nightlight bulb (7 watts, I believe). 'Smallish' meaning the switch would fit into a 1" cubic box or so (besides the shaft). It would be (surface) mounted in a box and not part of the power cord. When you first turn it you get a 'click' and the bulb lights at minimum brightness then goes to maximum when you turn it all the way around. Reverse the process and the bulb dims to minimum and then click off. Like the volume switch on an old transistor radio, only for a light. What exactly is the name for such a switch and what technical specs would I need to look for, or a specific recommendation would also be helpful. Thank you for your help.

 

I never heard of a dimmer on a night light. They are already dim. If you really want to do it, I would use a switched outlet & a regular dimmer in a gang box.

 

Thank you for your reply. This is a specific use for a project and I need it to fit these requirements. I've never heard of one either but that's what I need and that's why I'm here asking the experts. Yes a nightlight is already dim but I need to be able to bring it from zero to full brightness. I know almost nothing about electrical but what little researching I've done indicates some kind of potentiometer (sp?) or attenuator might work??

 

Dimmer 110v 100w triac diac potentiometer - YouTube

So you want a 110V potentiometer. That site shows the basic concept. I can't tell you how to actually make it happen. It might be a start.

 

Are there potentiometers that also act as an on/off switch? I'd like to have something all-in-one, like a miniature version of a wall-mounted rotary dimmer switch for home lighting. You either push to turn on/off then rotate to dim, or rotate to do both.

 

That won't work, you cannot install a dimmer to control a receptacle.

Why don't you just buy a dimmable nightlight. Home Depot and Lowes both sell them.

http://www.homedepot.com/p/Cooper-Wi...-K-L/203492496

 

That's beyond my scope. Maybe a local electronics store can help you with that.

 

Okay thank you for your help, Pulpo.

CasualJoe, thank you for the suggestion but it does not appear that would fit into a 1" cubic box.

 

No, it won't fit a 1 cubic inch box. Where would you even find such a box that is approved for a 120 volt device and how could you wire it even if you could find one?

 

It won't be going into a literal 1" cubic box. I mentioned that only to give a visualization of the approximate size I was looking for.

I figured surely there must be some kind of self-contained switch of that approximate size that will click on and off and also rotate to control the brightness of a 120-volt bulb. It didn't seem like that complicated of a device to me but evidently there's nothing out there that fills the bill, which is quite surprising.

 

Volume controls on analog sound systems used a potentiometer with a switch built in (turned the radio on and controlled the volume). A potentiometer is a type of rheostat. Rheostats can be used to directly control the brightness of an incandescent bulb on a low voltage DC circuit. (Wouldn't be practical on a 120 volt circuit because of the heat created.) so a battery a flashlight bulb and an old fashioned volume control might work.... or might let the smoke out of the volume control.

 

How about a plug-in dimmer?

Lutron Credenza 300-Watt Plug-In Lamp Dimmer - White-TT-300H-WH at The Home Depot


Or a screw-in dimmer?

GE Indoor Light Socket Dimmer - White-55431 at The Home Depot


You can source adapters to convert the medium base socket down to candelabra. You can also take the dimming circuit out of one of these.

 

Thank you ray2047 for the excellent alternative but it really needs to be 120v. That's exactly what I'm looking for, yes, a potentiometer with a switch built in, but I guess they are not for use with 120v. It appears that to accomplish the same thing with 120v some kind of circuit has to be added, you can't just use the potentiometer/switch directly as with DC.

Given that--thank you Justin Smith, I think both of those are possible solutions. Compact. Neither has an on/off per se but would take brightness down to zero anyway so perhaps a 'click' on/off isn't needed. Very good, thank you.

 

A dimming circuit is very easy to make. About five parts. Most of the dimmer circuits use a 250k pot with switch or 500k pot with switch.

You could google "miniature 500k potentiometer with switch" to see how big the actual control is.