Lighting Dimmer Switch Installed.

[traveldawg]

The DW and I pretty much considered the lighting directly over the recliners as useless. The 3 LED fixtures were just too bright to be used at night while watching TV. And the light was pretty harsh for reading.

I installed a dimmer in the lighting circuit and we'll test it this weekend while in the FL Keys.

The switch for that lighting is under the midship cupboard. I got 12v for the dimmer from the switched side of the switch that originally fed the lights and cut the ground wire that ran to the lights for the ground connection the dimmer required. I reconnected the 12v and ground for the lighting from the dimmer to the lights. At least there was a dedicated 12v and ground wire to those lights, otherwise the dimmer I chose wouldn't work.

I had to fish the wiring (12v supply; ground; lighting 12v; lighting ground) from under the cupboard into the wall between the cupboard and bathroom and into the open area behind the panel. It wasn't too difficult.

The photos explain how I disassembled the dimmer and mounted it inside the panel.

This is the before and after wiring diagram....


This is the switch I used, how I disassembled it, and how I mounted it to the lighting panel...

[andrewssteve]

The DW and I pretty much considered the lighting directly over the recliners as useless. The 3 LED fixtures were just too bright to be used at night while watching TV. And the light was pretty harsh for reading.

I installed a dimmer in the lighting circuit and we'll test it this weekend while in the FL Keys.

The switch for that lighting is under the midship cupboard. I got 12v for the dimmer from the switched side of the switch that originally fed the lights and cut the ground wire that ran to the lights for the ground connection the dimmer required. I reconnected the 12v and ground for the lighting from the dimmer to the lights. At least there was a dedicated 12v and ground wire to those lights, otherwise the dimmer I chose wouldn't work.

I had to fish the wiring (12v supply; ground; lighting 12v; lighting ground) from under the cupboard into the wall between the cupboard and bathroom and into the open area behind the panel. It wasn't too difficult.

The photos explain how I disassembled the dimmer and mounted it inside the panel.

This is the before and after wiring diagram....


This is the switch I used, how I disassembled it, and how I mounted it to the lighting panel...

Do you have any source info for obtaining the switch?

I didn't understand your comment: "At least there was a dedicated 12v and ground wire to those lights, otherwise the dimmer I chose wouldn't work." Can you clarify?

Thanks.

[Cate&Rob]

I didn't understand your comment: "At least there was a dedicated 12v and ground wire to those lights, otherwise the dimmer I chose wouldn't work." Can you clarify?

Thanks.

Hi Steve,

Most LED “dimmers” control the amount of light by cycling the LEDs on and off at a high frequency. They are called PWMs (pulse width modulation). The amount of time the LED is on vs the amount of time it is off determines how “bright” it appears. To do this, the PWM needs dedicated + and - for the LED circuit. It the ground for the LEDs goes elsewhere or combines with other grounds, the PWM will not work.

Rob

[Cate&Rob]

traveldawg - Nice dimmer installation!

I have done several similar installations. Some by reworking production switches as you did and some by building the PWMs from component kits. Search on “Awning Dimmer Rob” to find the many similar discussions that I have been involved in.

Rob

[howson]

The DW and I pretty much considered the lighting directly over the recliners as useless. The 3 LED fixtures were just too bright to be used at night while watching TV. And the light was pretty harsh for reading.

I installed a dimmer in the lighting circuit and we'll test it this weekend while in the FL Keys.

The switch for that lighting is under the midship cupboard. I got 12v for the dimmer from the switched side of the switch that originally fed the lights and cut the ground wire that ran to the lights for the ground connection the dimmer required. I reconnected the 12v and ground for the lighting from the dimmer to the lights. At least there was a dedicated 12v and ground wire to those lights, otherwise the dimmer I chose wouldn't work.

I had to fish the wiring (12v supply; ground; lighting 12v; lighting ground) from under the cupboard into the wall between the cupboard and bathroom and into the open area behind the panel. It wasn't too difficult.

The photos explain how I disassembled the dimmer and mounted it inside the panel.

This is the before and after wiring diagram....


This is the switch I used, how I disassembled it, and how I mounted it to the lighting panel...

Fantastic! Another project to add to my list...

[howson]

Do you have any source info for obtaining the switch?

I didn't understand your comment: "At least there was a dedicated 12v and ground wire to those lights, otherwise the dimmer I chose wouldn't work." Can you clarify?

Thanks.

This one looks similar: https://www.amazon.com/DC-12-Adjusta.../dp/B014GZ9J9W

[traveldawg]

Do you have any source info for obtaining the switch?

I got it on Amazon..... Switch
I didn't understand your comment: "At least there was a dedicated 12v and ground wire to those lights, otherwise the dimmer I chose wouldn't work." Can you clarify?
Thanks.

A lot of RV lights share a common ground; not all the time but a lot of the time. The ground and +12v for the 3 lights above the recliners have a dedicated wire that ties back to the cabinet the switch is in. As another poster explained, the type of dimmer I used (PCM) requires a dedicated + and - to control the lights.

traveldawg - Nice dimmer installation!
I have done several similar installations. Some by reworking production switches as you did and some by building the PWMs from component kits. Search on “Awning Dimmer Rob” to find the many similar discussions that I have been involved in.
Rob

Rob, I've seen (and followed) your dimmer posts. Thanks, and keep 'em coming!

an update.... tried the lights last night and they are now much more useful. I'll do the same mod to the 3 lights over the dinette when we get home.

[boyscout]

Most LED “dimmers” control the amount of light by cycling the LEDs on and off at a high frequency. They are called PWMs (pulse width modulation).

an update.... tried the lights last night and they are now much more useful. I'll do the same mod to the 3 lights over the dinette when we get home.

Is the on-off "vibration" of the lights at all detectable? Would someone who notices the flicker in flourescents notice a flicker in PWM-controlled LEDs? Thanks.

[Chiefblueman]

Is the on-off "vibration" of the lights at all detectable? Would someone who notices the flicker in flourescents notice a flicker in PWM-controlled LEDs? Thanks.

It's possible you will notice something. I have the main cabin lights on a remote control dimmer. At the lowest setting I perceive a slight glimmer but after a minute I don't notice it. I have the dining and sofa lights on touch dimmers and have no perceived flicker. Also installed touch control reading lamps above the bed and the recliners. No flicker.

[Cate&Rob]

Is the on-off "vibration" of the lights at all detectable? Would someone who notices the flicker in flourescents notice a flicker in PWM-controlled LEDs? Thanks.

I have never noticed any flicker in the dimmed LEDs. I don’t know what frequency they typically use, but I expect it is higher than the 60 Hz of 120VAC lighting.

Rob