Level Measurement Instrument

Prior experience with capacitance level suggests that all is well until the material in the vessel changes. A consequent change in permittivity runs the risk of either measuring short or of overfilling, if relying on the instrument alone. Given that capacitance needs to be viewed as a last resort technique for measuring level, the consequences of the latter could be disastrous.

Use with caution.

Funny you should mention that . . .

I fiddled around with the capacitive concept several years ago and never got it to perform with anything close to repeatable or reliable, so I figured, what the hell, I'll do it another way.

By the way, there are problems with bouncing ultrasonic beeps off the surface of some liquids too.

To overcome this problem usually there are two sensors, one as suggested and the reference one at the bottom of the container.

Then you calculate (may be done in the primary sensor circuit) C1/Cref.

This can directly give voltages U1/Uref.

This is independent of fluid changes.

But: any stray capacitances pose considerable problems, elimination by guarding should be tried but also not simple.

RHABE

weight it

The U.S. Navy uses TLI's (tank level indicators) on all their fuel oil and other liquids, but they don't rely 100% on them . They always sound their tanks periodically through a deck mounted access plug.

When all else fails, we tap on the side of the tank.

"Yup, it's about 50% full (or empty, depending on the type of person )".

regards,

Vulcan

well what I feel is the dielectric media that matter not so reliable