Haynes Forums

Haynes Forums (http://www.haynes.co.uk/forums/index.php)
-   Electrics (http://www.haynes.co.uk/forums/forumdisplay.php?f=7)
-   -   fuel gauge idea (http://www.haynes.co.uk/forums/showthread.php?t=673)

les g 22nd April 2008 02:37 PM

fuel gauge idea
:cool: what about the other type of float switch on the Maplins website
perhaps three arranged vertically
to three leds /lamps
red/amber /green
low /half full /full
what do think good /bad/crap/or bloody stupid ???????
any thoughts
les g: :eek:

jabs 22nd April 2008 03:45 PM

A little coarse, the last one could be set so you have say 1 gal left in the tank when it comes on. Also there would be no damping so as you go around corners it would be disco lights

les g 22nd April 2008 05:19 PM

ok yep i can see that
what about some baffling in the tank
or could they be wired in someway that they only trip the light if the float is continually activated for a specific time ie some kind of smoothing
or could thy to say five lights so at some position two floats are operating intermediate lights
any thoughts any clever electrical boffins??????
or just forget as too!!!! much hassleand junk the idea""""""""
les g:(

snapper 30th April 2008 08:17 AM

The output from the sender follows a specific range of resistance and with a little clever electronics is all you need to trigger the LED's.
Standard senders run 33 Ohms full tank to 240 empty.
You could have all LED's on when full and loose one every time the fuel level drops past a certain point.
With 5 LED's you could have 3 green 1 yellow and one red.


United States Patent 4102191 Link to this page:http://www.freepatentsonline.com/4102191.html Abstract:A digital readout fuel gauge for monitoring the liquid level in a fuel storage tank. The device utilizes a pre-amplifier circuit which comprises a voltage divider network utilizing the fuel gauge tank variable resistor on one side of the divider and a variable resistance on the other side which is connected to a signal processor. The output voltage of the signal processor is connected to the analog input of an analog to digital converter. The analog to digital converter changes the DC voltage levels to a four bit BCD code. The output carrying the code is connected to a decimal digit to a seven segment LED decoder. The digits are generated and displayed on LED indicator units. In addition, a voltage comparator circuit compares the output of the signal processor with a reference voltage and when said output is below a predetermined level, the comparator circuit initiates a warning signal.
Down to Maplin it is then

Josh 30th April 2008 04:17 PM

It wouldn't be to hard to do a DIY circuit that waits for say 4-5 secs before accepting that the fuel level really is that low, not just cornering. Would almost cirtainly need the use of a PIC (proggramable intergrated chip) and a little know how though. Try searching for 'PICAXE', I've used many of these chips and they have a great 'teach your self' section.


Chris Gibbs 30th April 2008 06:22 PM


That's the sound of anything electronic going over my head!


Chris :)

les g 30th April 2008 09:16 PM


Originally Posted by Chris Gibbs (Post 4548)

That's the sound of anything electronic going over my head!


Chris :)

yep thats a struggle i was thinking more like a handful of wires and a couple of diodes thats at my limit !!!
wot we need now is one of these boys to post something that says you do it like this tah dah !!! its easy (or i can make you one for a fiver ) even better
eh chris lol
les g :D :D :D

All times are GMT +1. The time now is 07:12 PM.

Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.