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Hello everyone,   I need some help with configuration of a Mitsu FR-D720 with a water pump.  Pressure target: 6 bar Sensor: 0..25bar , 4..20mA, connected to Terminal 4 of Inverter. Yes, the sensor range is suboptimal, I know. Pump: can make 12 bar, the pump should stop working when the 6 bar target is reached. Target: I want to use parameter 133 to set the pressure to 6 bar (no external adjustment, just set and forget) . I calculate 100%/25bar*6bar = 24%. So I set parameter 133 to 24. - PID action selection (Param 128) : "20" (PID reverse action) - RH-Terminal (Param 182) set to "14" (PID control valid terminal) - Terminal 4 input selection (Param 267)  set to "0" (Terminal 4 input 4 to 20mA) Question: What I do not understand are the parameters 904,905: 904    Terminal 4 frequency setting bias frequency    0 to 400Hz    0.01Hz    0    0         (904)    Terminal 4 frequency setting bias    0 to 300%    0.1%    20    20         905    Terminal 4 frequency setting gain frequency    0 to 400Hz    0.01Hz    50    50         (905)    Terminal 4 frequency setting gain    0 to 300%    0.1%    100    100         I have not understood the concept/relationship between frequency/percentage units of the parameters and pressure/mA on the input. Why do I have to or can enter a frequency? This relationship is unknown/dynamic. Do I have to do enter here some scaling (gain/bias)? The pump should run at full speed (50 Hz) with 4mA and should stop at 4mA+(20mA-4mA)/25bar*6bar=7.84mA . This might be done by the reverse PID setting in PARAM 128? If I do the scaling on the input, then I have another range for parameter 133? It would be nice, the value "60" is 6 bar and "40" is 4 bar in parameter 133. It would be nice, if someone can give some insights. I would like to understand these parameters rather than try and error to have a half baked solution. Have a nice day DWIM