TxEngr
Senior Member
- Location
- North Florida
We've had a great deal of theoretical discussion here but did Rey-Man get his question answered?
To summarize -
A few other suggestions as you look at this:
Now on with the theoretical discussions!
TxEngr
To summarize -
- Yes, you can apply a VFD to this application to help control the flow. This has the advantage of energy savings over other options.
- An alternative is to trim the pump impeller, but you can only trim the impeller so much and the effeciency losses become large.
- A VFD has a higher up-front cost, but it's long term cost is smaller with typical paybacks in the 1-3 year time frame on 500 HP and below applications
- personal experience on this number).
A few other suggestions as you look at this:
- Don't let the speed of the motor drop below 33% of rated RPMs for any extended period of time. The decreased airflow can adversely affect the motor.
- If you must run an 1800 rpm motor for extended periods at slower speeds, have your motor shop install a fan for a 1200 rpm motor to improve the air flow.
- Watch you cable lengths if you go with a VFD. If you have really long cable runs, it can adversely affect the motors life.
- Have someone who can read pump curves look at the application with you to make sure you're making the best choice.
Now on with the theoretical discussions!
TxEngr