Here's a question for you...
If a 12v negative earth system is using the dash board tell-tail bulb for the exciter line, what would happen if I upgrade the bulb for an led equivalent to make it brighter, remembering the led will only allow current to travel one way.
All opinions, including sniggering, welcomed!
Alternator tell-tail light conundrum
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Re: Alternator tell-tail light conundrum
https://electronics.stackexchange.com/q ... p-with-led
Looks like there are confusions out there!
Looks like there are confusions out there!
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Re: Alternator tell-tail light conundrum
The lamp only needs to pass current one way, so the fact it's a diode isn't the problem.
The problem is that it requires so little current to light an LED, it won't excite the alternator.
If you use 2W LED, it will excite the alternator and there is little chance you'll be able to ignore it.
Edit:
For reference, 2W is about right - (it's not just a random number)
The problem is that it requires so little current to light an LED, it won't excite the alternator.
If you use 2W LED, it will excite the alternator and there is little chance you'll be able to ignore it.
Edit:
For reference, 2W is about right - (it's not just a random number)
Last edited by gecko.cx on Thu Jun 15, 2023 4:23 am, edited 1 time in total.
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Re: Alternator tell-tail light conundrum
Thanks for the insights, I think I'm leaning towards the 'leave well alone' verdict for the moment as this machine needs lots of other things done as well.
Cheers.
Cheers.
If a LandRover doesn't leak oil, it's run out.
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Re: Alternator tell-tail light conundrum
I have a similar issue with 2 agricultural trailers with led lights. There is not enough draw on the indicator circuits to light the trailer warning light on the tractor dash.
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Re: Alternator tell-tail light conundrum
If the trailers are new they should have been fitted with resistors in the system to correct the draw. You get similar issues with can-bus cars and led trailers.
If a LandRover doesn't leak oil, it's run out.
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Re: Alternator tell-tail light conundrum
hair bear wrote:If the trailers are new they should have been fitted with resistors in the system to correct the draw. You get similar issues with can-bus cars and led trailers.
Not new but fitted from new.
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Re: Alternator tell-tail light conundrum
essexpete wrote:I have a similar issue with 2 agricultural trailers with led lights. There is not enough draw on the indicator circuits to light the trailer warning light on the tractor dash.
You can get flasher relays designed to run LED's for just this situation
CMN Stuff: MF65, Thwaites Nimline, JCB 3CX
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Re: Alternator tell-tail light conundrum
Slooby wrote:essexpete wrote:I have a similar issue with 2 agricultural trailers with led lights. There is not enough draw on the indicator circuits to light the trailer warning light on the tractor dash.
You can get flasher relays designed to run LED's for just this situation
How and where to fit?
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Re: Alternator tell-tail light conundrum
essexpete wrote:How and where to fit?
You replace the stock flasher relay with one like this:
https://www.ebay.co.uk/itm/272665874287 ... media=COPY
CMN Stuff: MF65, Thwaites Nimline, JCB 3CX
Projects: S11a 88" V8 Hybrid, 2 x S111 109"s, Mk11 Mini, Harrison L5A
Ish projects: T25 Camper, ST675R
Just added: Alpine S5 & Bridgeport Mk2
Sorely Missed: Impreza, E39 M5
Projects: S11a 88" V8 Hybrid, 2 x S111 109"s, Mk11 Mini, Harrison L5A
Ish projects: T25 Camper, ST675R
Just added: Alpine S5 & Bridgeport Mk2
Sorely Missed: Impreza, E39 M5
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