How to calculate Tank level measurement?

[KRAZE4LV]

I am measuring the tank level using level transmitter, Model=PLNH, range=0 to 1800mmH20, output=4 to20mA, 2wire and other model=SHT-100s

 4mA to 20mA.

How can I calculate the voltage to level?

[KRAZE4LV]

I am using Ni6251 voltage type DAQ

[Yamaeda]

1800/(20-16) = 112,5mm/mA

/Y

[KRAZE4LV]

1800/(20-16) = 112,5mm/mA

Please can you explain the measurement method..as the DAQ board can read voltage..

so I should apply the resitance and what is the voltage to level equation.

I could not understand your equation.