Controlling Powerflex 40 drives

[Conor 4]

Hi guys, I have a pump set that I have just installed three new Powerflex 40 Drives. I have set-up the drives and they are unning fine. I have a PID set-up and this will control ok too. Everything alright so far. Now I need to maintain a pressure of 7.5 bar with these pumps. One pump will not reach 7.5 on its own. I am not sure of which is the best way of running these pumps. Currently I have the Duty pump running flat out at 50 Hz. I am then using the PID to vary the speed of the Assist pump. Is this the normal way that this would be done? Or would I be better to run the two pumps from the PID and vary both? Any help would be great, Conor

[HKU_MS 0]

Hey Conor: I would look at varying the speed on both motors to keep the RPM/s up as much as possible depending on the pump low RPM operation could result in inefficent operation and most standard duty motors like to stay above 50% of there rated speed to limit heat build up in the windings but most of this depends on specifics of what type of motors and pumps are being used. and how far from your target pressure/flow a single pump gets you.