how do you plot a graph for the rt dash 2 fuel guage? do you just add a litre of fuel at a time and take a resistance measurement each time? also
where do you take the ohm reading from? at the sender end or at the dash 2? cheers
[Edited on 28/12/11 by daniel mason]
When we did it we did exactly as you said adding a 5 ltrs at a time. There is a facility in the software to set an equation based on what readings the
software gets at a set point.
i.e add the fuel then get a reading stick it in the column then add more and do the same then the same again and again till its full. the software
then plots the equation graph for you. AND it is very accurate and takes into account any changes in tank shapes etc ( if you had a spare wheel well
in it. Sorry its a bit vague but its a bit late at night and the thoughts are vague. Tommorow will be clearer if you need more help LOL
On mine i measured the resistance for the sender at empty and at the full position. I then generated an equation to get points in between. I might not be 100% but it would be close. And I took my readings from the sender end
We did it that way initially too femster, but as it was a rally car and the tank was not a uniform shape then it was not that accurate when trying to
decide the minimum amount of fuel for a set of stages.
Now remember the dash2 does not read resistances at all, only voltages. You will need to construct a ( someone remind me what its called please
perhaps a potentiometer divider?? ) really easy to do but you will need a 5volt reference and a resistor close enough to match your sender. Some of
the tronics guys on here will advise if you post up your readings.
Here are a couple of how to information links.
http://www.race-technology.com/wiki/index.php/HowDoI/ConnectMyOwnSensor
http://www.race-technology.com/wiki/index.php/HowDoI/ConnectMyFuelSender
Yes Omega, i have included a pull up resistor with my wiring. Also I have sized the resistors accordingly as the ranges on my sensors were different an max current from dash was 100mA.
There is a very useful speadsheet on this page
http://westfield-world.com/rtdash2.html
Gives you some interesting info as well.