vfd for a pump
- Thread starter smrithi25
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StephenSDH
Senior Member
- Location
- Allentown, PA
Are you sure it is a three phase motor?
cadpoint
Senior Member
- Location
- Durham, NC
- Occupation
- Electrician - but not by NC Law.
i want a variable discharge from a centrifugal pump. but the pressure should not vary. and also my input power consumption should go down. can anyone suggest me such drive and its details please...
One can't have both, The VFD will always be drawing more power to maintain
a constant pressure via a motor spinning. The VFD per it's self requirements can be made to understand the lose of volume or presssure this one application is understood per it use!
R Bob
Senior Member
- Location
- Chantilly, VA
i want a variable discharge from a centrifugal pump. but the pressure should not vary. and also my input power consumption should go down. can anyone suggest me such drive and its details please...
Control the pressure by allowing the drive to modulate the pump based on pressure set point.
Control the flow with a modulating control valve with an input from a flow control.
Power consumption will vary based on flow volume/the amount of work the pump is doing.
Decreased flow demand=increased pressure=VFD ramping down to maintain setpoint=reduced power consumption.
Increased flow demand=decreased pressure=VFD ramping up to maintain set point=increased power consumption.
Don't know what your specific application is, but this scenario is very similar to a chilled water loop.
To avoid serious problems, make sure the system is correctly designed/engineered.
weressl
Esteemed Member
i want a variable discharge from a centrifugal pump. but the pressure should not vary. and also my input power consumption should go down. can anyone suggest me such drive and its details please...
This is one of the most common application of drives. ACS550 series drive from ABB - among others - will accept a pressure transmitter 4-20mA signal and in the PID control mode it will maintain constant pressure. It will do that by increasing the speed of the motor if the flow demand increases and slows it down when the demand decreases.
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