Date: Tue, 27 Aug 2019 02:14:58 -0400
Reply-To: David Beierl <dbeierl@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: David Beierl <dbeierl@GMAIL.COM>
Subject: Re: Resistor for LED turn signal
In-Reply-To: <625696479.3023438.1566873490220@mail.yahoo.com>
Content-Type: text/plain; charset="UTF-8"
An 1156 or 1157 lamp is 27 watts, and the running light filament in the
1157 is about 8 watts. We know that if the 1157 is reversed in the front
turn signal, the resulting ~35 watt load is not enough to put the flasher
in slow-flash mode.
If you want to pretend to be a pair of 27 watt lamps you will have to
dissipate 56 watts of power, which is your give or take 2R5 resistor.
Undoubtedly you could get away with a higher value, as the flasher
threshold is somewhere between 35 watts and 56 watts. And of course you
get to subtract the actual draw of the LED lamps which helps a bit.
This is a power circuit and simply doesn't notice resistance in the
hundreds of ohms.
Yrs,
d
On Mon, Aug 26, 2019 at 10:38 PM Richard Koerner <rjkinpb@sbcglobal.net>
wrote:
> David...do you mean more like 2.5 Kohms instead of 2.5 Ohms for the inline
> resistors? Otherwise, I am confused.
>
>
>
> On Monday, August 26, 2019, 7:16:02 PM PDT, David Beierl <
> dbeierl@GMAIL.COM> wrote:
>
>
> Best to do as Alistair suggests. 470 ohms wouldn't even be noticed --
> you'd need more like 2.5 ohms with a 50 watt or better rating, to simulate
> the load of a pair of turn signal lamps. Wouldn't have to be at the
> lights, just anywhere in the circuit.
>
> YRs,
> d
>
> On Sun, Aug 25, 2019 at 4:19 PM Stan Shapiro <mail@stanshapiro.com> wrote:
>
> > 1977 Baywindow, 2 liter, Fuel Injected.
> >
> >
> >
> > I installed new LED bulbs for my parking/brake, backup, and turn signals.
> > Lighting is MUCH improved. I even added silver reflective HVAC tape on
> > the
> > inside of the light boxes.
> >
> >
> >
> > All work well, and the turn signals blink rapidly-as I pretty much
> > expected
> > they would.
> >
> >
> >
> > Suggestions on thesamba was to install a 470 ohm resistor to cure the
> > rapidly blinking turn signals. What is the easiest way of doing
> that??
> > I thought about adding a resistor, inline between a male and female
> spade,
> > and then patching that in right at the turn signal. I am thinking that
> it
> > has to be done on both sides? Electrical is not my strong point-and I
> > may be totally off base, so don't laugh to hard.
> >
> >
> >
> > Any suggestions.
> >
> >
> >
> > Thanks
> >
> > stab
> >
>
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