[nlh]

What should my spindle load meter read when the spindle is turning (no cutting, just spinning) at say, 2500rpm? How about 3000rpm? Currently it's pulling about 35 - 40% load when the spindle is turning around 2000rpm and goes up to about 50% at higher rpms. Actual cutting only makes the load meter go up 5 to 15% depending on what I'm doing. Maybe it's just me but this seems rather high. Is this normal? Is something out of adjustment? Currently it has a 10in. chuck, AC spindle motor and Fanuc spindle drive. The spindle is very smooth and easy to move. Any input?

Thanks

[Al_The_Man]

Depends where it is taken from and how accurate it is calibrated, put a clamp-on meter on the AC in to the drive to get some idea as to how meaningful the load meter is.
Is this a DC drive?
If the motor is input into a gearbox and has a heavy chuck and part the normal running current can be over 25%.
Al.

[nlh]

Thanks Al,

I will have someone come in and put a clamp meter on. The machine has a Fanuc AC spindle drive. This is fairly new territory for me having only run much smaller machines like SL-1's and such so I am not sure what to expect.