gen light

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BILLY BLACKARROW
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gen light

Post by BILLY BLACKARROW »

Some time back someone on here said not to use LED in dash gen light can anyone tell me why ,I have fitted LEDs through rest of car, I am running a alternator
BILLY BLACKARROW
MY Father always said do the hard part first --because when you are OVER IT you only have the easy part left to do THINGS I HAVE TRIED TO LIVE BY
ardiesse
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Re: gen light

Post by ardiesse »

I'd be wary of using an LED as the GEN light for a couple of reasons -

Polarity. The diode has to point in the right direction (electrically speaking), or it won't come on. Light bulbs don't care which way the current goes through.
Dynamic behaviour. Alternators don't self-excite like generators do, and the GEN light puts enough current into the alternator's field winding to make it "start up". An LED lamp won't pass enough current into the alternator's field winding to energise the alternator. Probably.

No doubt somebody will have proven me wrong, though . . .

Rob
ardiesse
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Re: gen light

Post by ardiesse »

Oh, and -

LEDs have a forward voltage drop of a couple of volts, so they don't fade out gently at low voltages like incandescent lamps. An LED appears to glow steadily as the voltage is reduced, until it just turns off.
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Harv
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Re: gen light

Post by Harv »

ardiesse wrote: Sun Dec 22, 2019 5:41 pm Oh, and -

LEDs have a forward voltage drop of a couple of volts, so they don't fade out gently at low voltages like incandescent lamps. An LED appears to glow steadily as the voltage is reduced, until it just turns off.
It would make it hard to set the idle... wind the idle screw down until the GEN light is just glowing, let it annoy you for a week then wind it up a smidge to stop the glow coming on at every traffic light 😀

Cheers,
Harv
327 Chev EK wagon, original EK ute for Number 1 Daughter, an FB sedan meth monster project and a BB/MD grey motored FED.
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BILLY BLACKARROW
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Re: gen light

Post by BILLY BLACKARROW »

Next question : Can you mix LEDs and incandescent lamps in the instrument cluster?? :ughh: :ughh:
BILLY BLACKARROW
MY Father always said do the hard part first --because when you are OVER IT you only have the easy part left to do THINGS I HAVE TRIED TO LIVE BY
ardiesse
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Re: gen light

Post by ardiesse »

Short answer: Yes.

But you'll really notice the difference in colours between incandescent bulbs and LEDs (even the white ones). You'd be best off making all your instrument lamps (grey wires) one type or the other. OIL, TEMP and hi-beam could be red LEDs if you want. I'd still go with incandescents for the turn signal lamps.
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Harv
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Re: gen light

Post by Harv »

ardiesse wrote: Mon Dec 23, 2019 7:59 pmI'd still go with incandescents for the turn signal lamps.
Is that because the LEDs don’t draw enough current to activate the original thermal flasher can? I ended up with a fancy electronic flasher can in the wagon. Doesn’t make the “click, click, click” noise, which irritates me.

Cheers,
Harv
327 Chev EK wagon, original EK ute for Number 1 Daughter, an FB sedan meth monster project and a BB/MD grey motored FED.
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BILLY BLACKARROW
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Re: gen light

Post by BILLY BLACKARROW »

Yes Harv
I new about that problem so I am going to wire a small buzza in line bought from Jay car. I have selective deafness anyway - :wink34: :wink34:
BILLY BLACKARROW
MY Father always said do the hard part first --because when you are OVER IT you only have the easy part left to do THINGS I HAVE TRIED TO LIVE BY
Blacky
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Re: gen light

Post by Blacky »

Harv wrote: Tue Dec 24, 2019 7:12 am
ardiesse wrote: Mon Dec 23, 2019 7:59 pmI'd still go with incandescents for the turn signal lamps.
Is that because the LEDs don’t draw enough current to activate the original thermal flasher can? I ended up with a fancy electronic flasher can in the wagon. Doesn’t make the “click, click, click” noise, which irritates me.

Cheers,
Harv
out of interest Harv , I got pinged for the indicators flashing too fast in my Chev because of LED rear indicators , and I bought a variable speed flasher can , it has a little pot on the bottom so you can slow down or speed up the flash rate.
When you're faced with an unpleasant task that you really don't want to do, sometimes you just have to dig deep down inside and somehow find the patience to wait for someone else to do it for you.


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