Dimmer switch for LED lighting in cabin

pateco · Jun 16, 2017

Try this
2-in-1 LED Dimmer with RF Wireless Touchpad

Or This

Single Color Key-Press LED Dimmer 12V 8amp

mcrow33 · Jun 16, 2017

I've been wanting to replace the switches on my 361. I also installed LEDs in all the overhead lights. The are so bright that it's blinding sometimes. So I will be interested if you find a solutions.

kloudie1 · Jun 16, 2017

An interesting thread indeed.. Most of the LED's sold for cabin use are not able to be dimmed unless specifically noted in the bulb's data sheet..

pateco · Jun 16, 2017

kloudie1 said:
An interesting thread indeed.. Most of the LED's sold for cabin use are not able to be dimmed unless specifically noted in the bulb's data sheet..

You cannot just use a standard rheostat to control LEDs. What these dimmers do is provide the correct voltage to power the LED, but in pulses using PWM (Pulse Wave Modulation). The frequency of the pulses determines the light level.

How to Dim an LED Without Compromising Light Quality

I have noticed that at really low light levels, when the pulses slow down, you may see these pulses as a mild flicker depending on your vision sensitivity and the quality of the PWM Module . Sort of how some people see the flicker on CRT TVs, and others don't.

Jackdaw · Jun 16, 2017

Captpete12 said:
Making assumptions usually gets one in trouble! I ordered my LED replacement bulbs through this website and ASSUME they can be dimmed? Anyone know? Thanks

To be precise, ANY LED component can be dimmed, with the right dimmer control. As Pateco notes, if the dimmer is designed for LEDs and is PWC based, it will be OK. But an old school rheostat dimmer will not, UNLESS the the LED FIXTURE has been designed for that, typically with a OP-AMP built in to supply the correct voltage to the LED component regardless of it dropping on the wire. It also then has to pulse the supply to the LED so it can dim.

pateco · Jun 16, 2017

Captpete12 said:
The 2 in 1LED dimmer mentioned in the above post seems to be the one. Spoke with the tech guy at Armacost this morning and he was able to answer all my questions - nice people BTY if you ever need assistance AND thanks all for your help in this matter.

Let us know how it works

Bill Roosa · Jun 16, 2017

I would beg to disagree. ALL LEDs can be dimmed by reducing the voltage only (you don't need a PWM circuit just a variable resistor aka rheostat). With that said you will note that the current bulb has either a resistor built into it to make it work with a 12 volt system or there is a resister on the board the LED is soldered to. All LEDs operate at 2-3 volts at the bear terminals. It does not matter which type you have as long as you just put the rheostat in SERIES with the power to the bulb/circuit board. Alternately you can play around with fixed resistors switching them in and out and just use a single double position switch (off-low-high). Higher resistance dims the LED more.
For the mathematically inclined non-electrical engineers you need to measure the amps (milliamp range typical) for the bulb. V=IR --> R=V/I, let V= battery voltage and I be the current you measured. R is the LED's resistance overall in ohms. If you double that the bulb will see 1/2 the amps and dim by something like 50%. So if you measured 2 milliamps =0.02 amps your resistance is 13.6/0.02=680 ohms. if you add a 680 ohm resistor (you will not be able to find one that matches exactly BTW as they come in standard "sizes") in series with the bulb it will see 1/2 the amps and dim by approx 50%. If you put a 680/4= 170 the bulb will dime by 25%.....
Radio shack has fixed resistors and the 1 watt version work fine.