Domoticz

I am looking for a dimmer switch type I can not find.
Perhaps I am not searching good enough.
I would like to be able to change the lower and upper limits of a dimmer from 0 and 100 to values like 150 and 300 or 30 and 70.
This way I could control a level of a device between the real limits of that device and have the actual value on the dimmer.
Now if the dimmer is for example on 75 % for a device with a range from 100 - 140 the value for the device is 130 and it says 75 on the dimmer which is confusing.
I would also like to change the unit which is a % sign now to any text like you can for the units of a custom sensor.

Is this not a calibration issue? Shutters like Qubino z-wave shutter have a calibration option: "78. Forced Shutter calibration: Start calibration process"

A theoretical example would be a pump of which I want to control the flow between let's say 137 and 259 milliliter/minute.
For that I would like a slider like on a dimmer with the unit 'ml/m' and lower and upper limits of 137 and 259.