Oil Level sensing design help.....

[SeanB]

If you have air to run the machine ( I would assume you do as most fillers use pneumatics, then you can just use a air bleed via a needle valve ( and put a 2 bar filter regulator ahead of it with a microfilter, 2 micron or less, oil coaleascing) and feed this into the bottle with the fill nozzle using a stainless steel thin wall 2mm tube. Then you can detect the change in pressure when oil covers the end, and use a pressure sensor to detect the rise in pressure. This will be a reliable method, just differentiate the output signal ( and add a comparator for redundancy) and detect the rising pressure to trigger the end of filling. You probably will have to have a reset contact to reset the differentiator per cycle so it starts at zero voltage for each fill.

[aruna1]

machan,
use capacitive method.
make an oscillator with 7414 schmitt trigger,resistor and your oil can as the capaciitor. measure the frequency with the PIC,
I have done this to sense fuel level in a fuel level meter. it works and it is pretty accurate