Hi Beam Reducer

[kaapso]

I used two relays to add daytime running lamps using the high beams bulbs. I want to add a reducer to the hi beam for lower intensity when drl is on. I bought this Potentiometers, Variable Resistors , http://search.digikey.com/us/en/prod...-100-ND/257625, but it would not work.

I do not know why, and do not know much of electronics at this level, could someone recommend a potentiometer that would do the job of reducing the head light brightness.

Thank you.

[Mongoose1]

Save you some time and just buy the module. You can check this out. http://www.sav-a-life.com/Drl_specs.htm

[kaapso]

Save you some time and just buy the module. You can check this out. http://www.sav-a-life.com/Drl_specs.htm

I thought about several module but could not decide on any. The module at the link you provided does not have a delay. I build a 9 second delay timer which will turn on the drl circuit 9 seconds after the ignition is turned on.

All I need now it to reduce the brightness of the high beam.

I could not believe the potentiometer I bought would not work. It says 25w, maybe I should have gotten a 55w potentiometer. Not sure about he ohm.

Anyway, since I already spent the time and install the drl circuit, buying a module would not save any. The drl is working but at full intensity.

[Mongoose1]

Any reason why you really need a 9 second delay to fire up your DRL's? Have you tried to reduce the voltage to reduce the beam intensity?

[kaapso]

Any reason why you really need a 9 second delay to fire up your DRL's? Have you tried to reduce the voltage to reduce the beam intensity?

No particular reason for the 9 second delay. My 09 crv has the delay and I thought since I am building one I should add the delay which I happened to like.

Reducing the voltage is exactly what I want, but how? The potentiometer is not the most efficient way, other ways are more complicated. The potentiometer wastes current by dissipating it as heat. It is simple to use and add to my circuit.

[CaughtOnRadar]

One thing to remember. Your potentiometer/resistor has to be in serie with your high beam filament. If you had it connected accross the high beam, known as parallel, it will not reduce the intensity. That resistor will be extreminly hot, make sure it is in a well vented area, the best place will in the engine compartment.

[kaapso]

One thing to remember. Your potentiometer/resistor has to be in serie with your high beam filament. If you had it connected accross the high beam, known as parallel, it will not reduce the intensity. That resistor will be extreminly hot, make sure it is in a well vented area, the best place will in the engine compartment.

I connected it in series. With the prongs toward me, I put negative on the left prong and positive on the right prong. The middle go to the high beam. This is my problem it would not work.

I tested it with a 12v adapter 500 mill amps and it works. It would reduce the power which I tested with a multi meter.

When I added to the drl circuit it would not work. It seem the voltage is too much for it.

I was hoping someone with knowledge of it can give me the right amperage and wattage potentiometer.

[Gravy]

The bulbs are 12V 55A so whatever you use will have to be at least that or better if you use one for each. If you use one for both it would have to be at least 12V 110A. An alternative may be to use the relays and some more wire to make the bulbs work in series. That would be like reducing the voltage to 6V. With a relay isolate the ground on one bulb and connect it to the positive of the other with another relay.

[CaughtOnRadar]

Gravy, you are confusing amp. & watts. High beam are 55w not 55A. Kaapso, according to my calculations, you need to introduce a 4.5 ohms in serie with the high beam filament, this value should reduce the intensity by approx. 50%.This should give 27 watts at the filament and 27W at your resistor. The resistor you purchased is 25 W, you will need a bigger wattage otherwise yours won't last long. If someone can double check my calculations, it would be nice, has been a while since I have done that.

I just double check, probably 5 ohms be better, calculations were done at 12 V not 13.5. and you will need one resistor for each filament.

[kaapso]

Gravy, you are confusing amp. & watts. High beam are 55w not 55A. Kaapso, according to my calculations, you need to introduce a 4.5 ohms in serie with the high beam filament, this value should reduce the intensity by approx. 50%.This should give 27 watts at the filament and 27W at your resistor. The resistor you purchased is 25 W, you will need a bigger wattage otherwise yours won't last long. If someone can double check my calculations, it would be nice, has been a while since I have done that.

I just double check, probably 5 ohms be better, calculations were done at 12 V not 13.5. and you will need one resistor for each filament.

Ahh, the wattage. I will get a 60w 5 ohms potentiometer. Or something close to 60w. I will post after I get it.

Much thanks for the information, CaughtOnRadar.