I need to figure a way (with a relay or whatever) to dim one set of lights when another gets turned on.
I’m figuring a relay of some sort gets tripped when 12v hits it, and that in turn runs lower voltage via a resistor or something to the second set of lights, thereby dimming them. When the first set turns off, the relay trips back and the second set goes full bright again.
Ideas?
Could you just use a 3-position switch?
Yeah but I just don’t want any ghetto rocker switches or anything. I was hoping to make it occur on its own. I forgot to mention, the set I’m dimming is LED, which makes it somewhat tougher.
So you’ve got 2 sets of lights and you need the 3 following options?
Both sets on full
Set A on, Set B dimmed
Both sets off
Do you want it so that Set B is dimmed as the “base” state on your light switch but it was wired into your car’s “accessory” switch? This would keep Set B on any time the car was on, but it would be dimmed unless you activated the other light switch. I’ve seen multi-element switches that might handle this type of setup, let me see if I can find anything for you.
Edit: Sorry I misread the original post. Sounds like Joe can help you.
A. Low beams off- LED’s on full bright
B. Low beams on- LED’s dimmed by half or so
That’s all.
I’d contribute to this, but I feel as though this is for some sort of ricey endeavor therefore I shall not.
I can do it.
You have to Isolate the 2 with exactly that A Relay.
When you say LED’s where are these? are they high power? Are they just a Raw LED? I belive leds like 2.1 Volts to begin with or something like that.
Newer Audi OEM equipment has LED’s dim when the headlights turn on. I would like mine to do that.
Here is thread of how project is progressing. Click
The final project does not have an LED “strip”. It will be single 10mm LED’s from an Audi S6 wired in series.
Oh, yeah, each headlight will have 13 LED, and each 10mm 1w LED has it’s own resistor already. The problem is, LED’s don’t dim in the same manner as regular bulbs. Cutting voltage doesn’t have the same effect.
With standard LEDS Its 2.2mA the OEM **** is prob like 5K. you would need like a 12K resistor and a Single Pole Double throw Relay.
Thanks. Gotta try to find a schematic now so I wire it up right.
Here are specs for LED:
High Power 20-80mA 4 chips White 10mm LED
Vf: Typ 3.3V
Iv: 10000-18000mcd @ 80mA, Total power 825,000mcd*
Iv: 20lm @ 80mA Max, 1W power ~53lm*
Viewing Angle: 55 Degree
Color : Pure White
They will be wired in series of 13 inside each headlight.