1. What is Pressure?
Pressure is the force exerted per unit area critical in various applications. It ensures efficient industrial processes, regulates fluid flow, and maintains safety in systems like pipelines and tanks. Rheonics Type-DV sensors have the versatility to write over Modbus (either RTU or TCP) a set of registers associated with the pressure input on DV sensors.
| Writing Pressure back to the Rheonics Type-SR sensors is possible, but is only relevant to high-pressure systems |
2. Modbus registers
There are holding registers associated with pressure compensation value. The two holding registers of each coefficient should form a float 32 data type in Big Endian format.
The registers are password-protected. You should input the user password in the holding register 0 to write to the coefficients.
You can use the software of your preference to write to the holding register. The Write function to write to multiple registers is 16 and to read the holding registers the function 03 shall be used.
| Register | Holding register Address | Data Type |
| Password | Address=0; User password=0x5312 | Uint16 |
| Pressure compensation | Address=1260 and Address=1261 | Float32 |
Below is an example using ModbusPoll software to get constant density:
a. Write the password into the holding register 0.
Figure 1. Input password on register 0
b. Write a constant value for the pressure compensation value. This is useful when we have a real-time pressure value from a pressure gauge that can transmit data to the Rheonics register using a PLC.
Figure 2. Pressure compensation value
c. To confirm that Pressure is correctly written we can go to the Rheonics Control Panel and verify.
Figure 3. Pressure value as seen on the RCP software
3. References:
2. https://support.rheonics.com/en/support/solutions/articles/81000406158-external-pressure-sensor-how-does-it-work-with-the-rcp-software-