Modbus integer - scaling value

Davorin Vuga 2 years ago in Devices / Modbus updated 2 years ago 3


we try to connect Modbus TCP/IP thermostats with ComfortClick. All works OK.

We want to ask, how we can scale ratio of the holding register?

We have the value of the set temeperature, which needs to be scaled by 0.02 (or divided by 50).

If we use the "calculation" function, it is works for the input register (read), while the holding register is a problem because it is a read/writte.

so please help us.


You could probably do it with a program triggered by value onChange, with a variable representing the Holding Register lets say a setpoint, which when changed writes to to the holding register, and a program when the holding register changes writes to the variable. Still need to put them both through calculation. Sounds a bit clunky but done once can be copied and pasted?

Thanks for answer.

Chang of modbus holding register, can be made from device, and also from comfortclick panels.

How could do it, that it works in both direction?


We resolved problem for scaling of Modbus registers.

We use two-program function, one for read value from device to CC, and second for write value from CC to device. The program is trigger by changing value (such as value from device) and set – write changing value to other value (to CC).

It works well, but you should not use “allow retrigger” option (uncheck).