DIY Electric Car Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
70 Posts
Discussion Starter #1
I have a Gizmo EV which uses green LEDs for the turn signal
indicators. The brightness is perfect for daytime driving but they are
extremely blinding at night. What would be a relatively simple way to
dim them for night use? Would a resistor in the line do it? If so, I
could then hook up a switch which could short across the resistor for
daytime use. The blinkers are run by a smart-blink system which I
think is used on motor-cycles and/or mopeds. I also believe these are
on the 12V side of my DC-DC converter.

--
David D. Nelson

http://www.austinev.org/evalbum/1328

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #2
From: David Nelson
> I have a Gizmo EV which uses green LEDs for the turn signal
> indicators. The brightness is perfect for daytime driving but they are
> extremely blinding at night. What would be a relatively simple way to
> dim them for night use?

The standard automotive scheme is to have a resistor or adjustable rheostat that is shorted when the headlights are off, and switched in when the headlights are turned on.

You could also add a light-sensitive resistor (cadmium sulfide cell) in series with the LED. In bright light, it has very low resistance; as the light falling on it dims, its resistance increases. They will increase to megohms in total darkness, so you'd need a fixed resistor in parallel with it to set the LED brightness at night.

A phototransistor could be used the same way, but may have too much voltage drop or not enough light sensitivity to visible light (they respond best to infrared light).


--
"Excellence does not require perfection." -- Henry James
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart-at-earthlink.net

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #4
Green turn signals??
Not legal anywhere in the USA as far as I know. If it were legal, you'd
be seeing teenagers mod this left and right. Many locales have even
fought the purple button on the taillight to "violet" them a bit with
some frequent ticketing.

Danny

David Nelson wrote:

>I have a Gizmo EV which uses green LEDs for the turn signal
>indicators. The brightness is perfect for daytime driving but they are
>extremely blinding at night. What would be a relatively simple way to
>dim them for night use? Would a resistor in the line do it? If so, I
>could then hook up a switch which could short across the resistor for
>daytime use. The blinkers are run by a smart-blink system which I
>think is used on motor-cycles and/or mopeds. I also believe these are
>on the 12V side of my DC-DC converter.
>
>
>

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #7
>From the original post, I was under the impression that the turn indicators
to be dimmed were the ones on the instrument panel, not the ones on the
exterior of the vehicle. If this be true the color green's compliance (or
non- ) with DOT indicators requirements is of no consequence.

David Roden
EVDL Administrator
http://www.evdl.org/


_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 
1 - 7 of 7 Posts
Top