Diesel Flow Meter

At this time, the forum doesn't even know such basic things as line size and max flowrate. Is this instantaneous flow? Totalising? Dispesing? What?

Electromagnetic won't work as the fluid is non-conductive.

What is the specification? Please list the instruments under consideration so far so that inappropriate ones can be deleted from the list.

You cannot use an electromagnetic flowmeter (magmeter) because diesel fuel is non-conductive, which violates the principle of operation for a magmeter, fluid conductivity.

Turbine meters were initially designed for measuring and metering clean petrochemical fuels. It is nearly the ideal meter, since the fuel lubricates the rotor bearings.

Turbine meters output a pulse. The electronics box that reads the pulses and calculates the flow rate, the transmitter or the converter, will have be the unit that has or doesn't have a digital protocol interface.

Does this tank store fuel for a diesel generator, boiler burner or other consumer that also has a return line back to the tank?

If this is the case then you need to think carefully here.

Diesel flow meters always use a positive displacement flow meters which is a mechanical type like picture shown.