User avatar
Mats
Verde
Verde
Posts: 4059
Joined: Mon Nov 29, 2004 12:26 am
Location: Gothenburg, Sweden
Contact:

Post by Mats »

A PWM signal to the bulbs would seriously shorten the life of the bulb. The bulbs doesn't like to get a varying current, that is why I even have the bulbs wired to not be turned on when I crank the car (current will be "dirty" because of the load from the starter).
Looks very modern when the lights come on when the engine fires. :)
Mats Strandberg
-Scuderia Rosso- Now burned to the ground...
-onemanracing.com-
-Strandberg.photography-

GTV 2000 -77 - Died in the fire.
155 V6 Sport -96 - Sold!
Jim K
Verde
Verde
Posts: 1751
Joined: Tue Nov 30, 2004 12:10 am
Location: Athens,Greece

Post by Jim K »

I don't know Mats, the incandescent characteristics of filament bulbs will not behave like an 'on/off' load I think, but will see a much smoother voltage than what will show up on a scope. I don't have any data on bulb life when used with PWM supply. It all comes down to what your pocket can term reasonable cost for replacing bulbs vs the ability to regulate light output
Jim K.
User avatar
DaveH
Gold
Gold
Posts: 179
Joined: Thu Dec 02, 2004 8:40 pm
Location: Atlanta, GA

Post by DaveH »

Guys, a PWM circuit is not necessarily a choppy waveform. The correct size capacitor in parallel with the output can smooth out the waveform. PWM circuits will often incorporate this, sometimes with inductors in series.

I'm not sure, but voltage dividers prob use such circuids. Allied Electronics (US), Radionics or Farnell in the UK will stock such items. Or you could just go with a basic resistor network voltage divider, like Mats mentioned.
MerrilGordon
Gold
Gold
Posts: 166
Joined: Wed Dec 29, 2004 5:55 pm
Location: Marysville, WA. USA

Post by MerrilGordon »

Well it sounds like the quad headlight arrangement is not such a good idea as MD reports. Did you have the same problem with oncoming traffic Mats ?

Thanks,
Merril
82 GTV6 3.0
MerrilGordon
Gold
Gold
Posts: 166
Joined: Wed Dec 29, 2004 5:55 pm
Location: Marysville, WA. USA

Post by MerrilGordon »

Clarification; I ment quad low beams.

Merril
82 GTV6 3.0
jrreeve
Gold
Gold
Posts: 83
Joined: Wed Dec 01, 2004 5:40 am

Post by jrreeve »

Just installed an adjustable voltage regulator(Transpo)...that was fun!!! Now anyone know which way to turn the screw to turn it up. Don't like getting burned by the exhaust manifold everytime I try and reach down there. Would rather know before I start turning the wrong way! Thanks in advance!

Rob
Post Reply