LED 'fuel gauge'

[Dingo2024]

Just come across this, not sure it has been looked at here before;

LED "fuel gauge" measures your battery voltage to a few 10ths of a volt! Provides an indication of remaining battery power. Mounting posts and brass screws included. Simple 2 wire hookup. Instructions. Available in 24, 36, and 48 volt versions. YOU supply the housing and mounting method.

about half way down this page;

http://www.evdeals.com/LashoutParts.htm

is this of any use and is it accurate enough to be used as per a regular 'car' fuel gauge; also would it work with all battery chemistry's?

thanks,

Ian

 

[Old_Scoot]

My guess it that it works fairly well with lead acid but less so with other chemistries. Sounds like it is just measuring voltage drop with use. Lead acid has a very predictable voltage drop, other chemistries less so.

 

[Harold in CR]

Back in another life, I had a Magnetometer Business. The Tech was always goofing off, so, I had him design a battery "Fuel" gauge. It consisted of 4 LED's, that had resistors on each one. It had 2 green 1 amber and 1 red. It would tell about what stage of charge was in the batteries.

We used NiCd's in Metal Detectors, and it worked very well. I still have 1 in Fl, I think. We used a 2" PVC Pipe cap, flat top, and drilled holes for the 4 LED's. Potted the Whole shebang with West System, that I used to pot new loop coils for the underwater detectors.

 

[dogman dan]

Similar to the led fuel guage in my Fusin kit. It came with a light with built in horn and fuel guage. With lifepo4 of course, it would have all the green leds lit anytime the bike was not running, right up till the battery bms tripped. But while riding, it gave good readings of voltage sag once about half the battery discharged. So right there you had a sort of half way guage. Also it helped with learning to ride more efficient, since you could see led's lighting up or not depending on how much throtttle and how much pedaling you were doing.

So while it never really worked as a fuel guage, it kicked ass as a how am I doing at riding efficient meter. If you rode so all the green led's stayed lit, you had to be doing OK.