Hydroracer
Plastic
- Joined
- Apr 21, 2020
Hello,
Have read through a few threads here and it seems there's some quite knowledgeable folks when it comes to VFD's and motors, so I have question(s):
I endeavor to build a 2x72 belt grinder for my knife making. Of course, I want to make it speed controlled with a 3-phase motor and a VFD (3HP). What I'm not sure on is the "mode" to run it. I've done a fair bit of reading about VFD's and motors and I understand things for the most part, but that reading also states that grinders are best suited for a "constant HP" mode. That means the motor has to run at or above base RPM if I understand VFD operating principles correctly? Of course, by default, if you go below base RPM, then you are operating in a constant torque mode. I also understand that most "decent" VFD's (I'm looking at a KB Electronics KBAC series) will run down as low as around 30% to around 90% above normal operating frequency (60Hz in my case).
I guess my question is, would it even be feasible and desirable to set up the grinder to run exclusively in a constant HP regime, or would it be better to run things in the given range of whichever VFD I get and not worry about it?
I'm mainly concerned with two things: heat build up at lower RPMs over extended use periods and not bogging down the grinder under heavy use.
Have read through a few threads here and it seems there's some quite knowledgeable folks when it comes to VFD's and motors, so I have question(s):
I endeavor to build a 2x72 belt grinder for my knife making. Of course, I want to make it speed controlled with a 3-phase motor and a VFD (3HP). What I'm not sure on is the "mode" to run it. I've done a fair bit of reading about VFD's and motors and I understand things for the most part, but that reading also states that grinders are best suited for a "constant HP" mode. That means the motor has to run at or above base RPM if I understand VFD operating principles correctly? Of course, by default, if you go below base RPM, then you are operating in a constant torque mode. I also understand that most "decent" VFD's (I'm looking at a KB Electronics KBAC series) will run down as low as around 30% to around 90% above normal operating frequency (60Hz in my case).
I guess my question is, would it even be feasible and desirable to set up the grinder to run exclusively in a constant HP regime, or would it be better to run things in the given range of whichever VFD I get and not worry about it?
I'm mainly concerned with two things: heat build up at lower RPMs over extended use periods and not bogging down the grinder under heavy use.