other posibility is using a ribbon cable an measuring the capacity between
two wires. The fluid level around the cable changes the capacity between
the two wires. Use a CMOS Mono Flop for converting capacity to
time varaiation. The Pulsetime from the Monoflop can be counted by
a little µc like a PIC.
Good luck, Halabat
PS: don't forget to isolate the end of the ribbon cable
other posibility is using a ribbon cable an measuring the capacity between
two wires. The fluid level around the cable changes the capacity between
the two wires. Use a CMOS Mono Flop for converting capacity to
time varaiation. The Pulsetime from the Monoflop can be counted by
a little µc like a PIC.
Good luck, Halabat
PS: don't forget to isolate the end of the ribbon cable
Hmm.. as Flatulent stated, safety is an important issue. If somehow you'll have an ESD discharge in the measuring wires when operating or servicing the module, the result can be pretty ugly.... Also, in time, residues of fuel can deposit on the wire and this will affect the long time reliability of the measurement.
May be water isolated pressure sensor put on bottom of tank could serve your purpose ? Or you can install it on top if put into tube on one side while making other side open . Then you should mount open side of tube down to bottom of fuel tank .
Also look to the car's fuel tank sensors - there are old simple ones you can use .
If you're looking in a modern tank of a car you'll see an in-tank fuel pump
where all wires are blank. So the insulation isn't as critical i think. Or look
at Bosch's injections, there are even inline fuel pumps where the fuel
flows through the DC Motor.
But i agree with pisoiu the long time reliability could be a problem...
Hello,
You must remember that, usually, pure combustible is not explosive. The air-combustible gas or vapor mixture IS explosive within some limits. I think that the interior of a fuel tank is not the place to make experiments, specially if you are seating on it.
Best regards.
Mesuaring level using Ultrasound waves could be a bit difficult in a bike tank. Two reasons come to my mind:
a) Waves on the surface of gasoline produced by the movement of the bike inside the tank could produce inaccuracies, and filtering it could result very difficult.
b) Echoes of the ultrasound energy inside the tank could mask the measurement process.
As far I have seen, modern car manufactures measures levels using a floating device that drive a variable resistor. All the system is place inside the tank.
So, I sugest you to use some kind of floating device adapted to the bike tank and convert the resistance value to digital.
The issue about the risk of explosion is something to take in account. I don’t know how it is solved by car manufacturers. I have seen several standard level meters of commercial cars and I haven’t seen anything special o different. In fact, come to my attention that the variable resistor seems to be inside the tank without any special protection.
Anyhow, there is a technique used in hazardous areas known as Intrinsic Safety that I recommend you to take in account. The main idea laid on the fact that it is necessary certain amount of energy to trigger an explosion. If the amount of energy is kept below that level, the system works in a safe level.
Please find an explanation about Intrinsic Safety in: https://www.omega.com/techref/intrinsic.html
Another issue would be: fuel level measuring is required for different sollutions which can be installed on vehicles (datalogers for trucks, etc.). But some of these vehicles are new, and interfering with own car's fuel measuring equipment will not be allowed because of the waranty. Punching tank and installing different stuff is also excluded. So, a non-invasive method would be more apropriate in these cases. Are there any methods, besides ultrasound?
u can used crystal as a sensor. The preasure will change a oscillator frequency. So u can build a crystal oscillator and measure the frequency. Put the crystal at the bottom of the tank.
Hi
Can you be more specific of using a crystal.you mean that I should fix the crystal inside the tank and measure the frequency. How do i isolated the crystal