Level Measurement Solution For Closed Tank

The PR5115 Signal Calculator is a calculator that converts the measurement signal between 2 input signals with 4 arithmetic operations giving the user the option to calculate difference or average calculations. Along with that is the function of signal redundancy and copy input signal from temperature sensor, converts the analog signal to 2 analog output signals. With a universal AC/DC power supply suitable for all types of power sources and signal isolation up to 3.5kVac ensures a safe and accurate signal that is not disturbed by factors such as the environment and other equipment in the field.



Specifications of The PR5115 signal calculator:

The PR5115 is a product of PR electronics – Denmark and is exclusively distributed by VIET NHAT Industrial Equipment CO. Ltd in Vietnam

  • Inputs for RTD, TC, mV, linear resistance, mA and V
  • Redundant measurement with 2 input signals
  • Calculate the difference with four arithmetic operations: Add, subtract, multiply and divide
  • LEDs indicate normal operation, sensor failure on each sensor, and function failure
  • Universal power supply: 24…250V AC/DC
  • Signal isolation: 3.75 kVac
  • Function to copy the input signal to two separate analog outputs
  • Warranty: 5 years

Application for Level measurement solution for closed tank:

In this article, Viet Nhat would like to introduce a measure method with a set of 2 pressure sensors mounted directly on the top and bottom of the tank to measure the pressure value of the empty part (no liquid) and the part containing the liquid and then output this signal . The analog signal is sent to the PR 5115 signal processor to calculate and output the pressure difference between these two sensors and give a signal of 4…20mA corresponding to the liquid level inside the tank.


With this method of measuring liquid level in closed tanks, the advantages are:

  • Lower cost compared to other measurement methods.
  • Easily optional equipment to suit corrosive or explosive environments.
  • The input and output signal isolation level up to 3.5kVac is very safe to send the signal to the DCS, HMI…
  • Easy to install and use.

Especially in applications with corrosive, adhesive tanks, it is easy to choose a pressure sensor with a diaphragm connection to use without reducing sensor life. Or in high temperature applications, we simply need to add cooling to reduce the temperature of the pressure sensors.