Constant Pressure Water Supply

Kinda VFD applied in constant water supply system (PID control)

1, Load feature
   (1) PID function is required.
   (2) There is a pressure sensor in the system.
   (3) In theory, if the running frequency is H1, then
        Energy Saving = 1-(H1/50)3
2,  Requests for frequency inverters (VFD)
   (1) Soft start the motor, reduce the surge current.
   (2) PID control should be stable and accurate.
3,  Typical wiring diagram

4,  Parameters setting list

No. Function codes Default Setting value Explanation
1 F0-02 0 1 Start / stop by external signal (If necessary)
2 F0-03 1 8 PID control
3 F9-00 0 0 PID target value set by F9-01
4 F9-01 50% -- Set suitable value depend on system
5 F9-02 0 0, 1 Pressure feedback channel (VI or CI)
6 F9-08 2.00Hz 0.00 Cutoff frequency of PID reverse
7 F8-48 ~ F8-52 -- -- Set suitable dormancy and wake up parameters.

5,  Notices
   (1) select a suitable pressure sensor, the calculation of F9-01 as below
        if the pressure sensor measure range is 16bar (1.6Mpa), and the
        target pressure is 5bar (0.5Mpa), then F9-01=5/16*100%=31.3%.

   (2) Maintenance regularly, pay attention to dust and humidity prevention.