gen light

[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

[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]

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.

[Harv]

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

[BILLY BLACKARROW]

Next question : Can you mix LEDs and incandescent lamps in the instrument cluster??

[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.

[Harv]

I'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

[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 -

[Blacky]

I'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.