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Subject:Re: 758227.jpg
From:John Bange
Date:Tue, 25 Oct 2005 13:14:00 -0700

>
> So that brings me back to my original question - why do you need two
> 30-amp relays to switch two 55-watt (or 80-watt for that matter) bulbs?
>
> AFAIK, the high beam current doesn't ever go throught the headlight
> switch, adding an additional set of relay contacts doesn't make any sense.
>

One relay each for the high beam and low beam circuits. If you only use one
relay, you'd have to put it before the dimmer switch so that power could be
directed to hi or lo as necessary-- a circuit of:

+12V
|
Relay(controlled by headlight switch)
|
Dimmer(Lo Leg)------HiBeams----->Ground
(Hi Leg)
|
LoBeams----->Ground

TWO relays placed AFTER the dimmer gives you a lighting circuit consisting
of:

+12V-----Relay(controlled by dimmer Hi leg)-----HiBeams----->Ground
|
Relay(controlled by dimmer Low leg)
|
LoBeams----->Ground

Best to have all the potentially delicate and/or expensive VW switching gear
(like the dimmer!) relegated to supplying only the 250ma or so needed to
trip the relays. Relays are cheap!
--
John Bange
'90 Vanagon
"We'd tell a monkey how to peel a banana, if he said he was peeling one in a
Vanagon."