ecodes (Customer) asked a question.
Hello, this seems super simple but I'm not getting too far in this from the manual.
VFD - Fuji Mini C2
Motor - 2 hp 3 phase
Pressor sensor - Wika a-10, 4-20mA
I have a Fuji mini C2 VFD and a 2hp motor. First I'm looking to use an analog input pressure sensor/trandducer (2 wire) and "program" the VFD to then turn the motor On/Off between 2 pressure points. Ex. at 4000psi turn motor on, at 6000psi turn motor off. Once it hits 4000psi it should turn back on until 6000.
I was looking at the PID for analog in and then doing the closed loop but that may be overly complicated and more for keeping the motor running at X psi instead of a simple run/stop.
In looking online people seem to mention some models (non fuji) having setpoints but I'm not finding that unless I don't see it yet.
Any help would be appreciated!
I don't know if you will be able to set up the drive to start and stop based on analog input values, but the PID appears to be workable. It looks like Fuji calls the Process Variable "PID Feedback" and the Setpoint is called the "PID Command". I say this with a level of certainty nowhere near 100%.
Constant pressure control is so common that almost every VFD supports it, but not all of them give a clear example of the required settings in their manuals. They do a pretty good job of explaining how to get the display to show engineering units for "Command" and "Feedback" with parameters E40 and E41.
EDIT: Reading further, this manual I found does give a PID example that is not bad after all. It also describes parameters J15 through J24 that are frequently referred to as "sleep" and "wake" settings by other manufacturers. This means that if the VFD satisfies the pressure setpoint and the pump has slowed to a speed at or below J15 (in Hz) for a time period of J16 seconds, it will stop.
Then, if the pressure deviates (drops below) the setpoint (PID Command) by a percentage specified in J23 for a period of J24 seconds, it will start back up.
The manual I am looking at is titled "User's Manual Frenic Mini (C2) Series" and has on the bottom of the title page "24A7-E-0023d" which I assume is a document number.
Thank you so much for the reply. Once you mentioned the PID command I was digging into that and I thought you may have found a good way. Still trying to work out the on/off at different pressures. It seems like such an easy task but so hard to accomplish on this vfd.
Thank you for the help. I'll be looking at this and the new info and see what we can come up with. We also contacted our Fuji rep.