smithy VFD 1240 User Manual

Programing VFD

Q: I have noticed that the drive motors for the XYZ axes and spindle take a while to accelerate and

decelerate on my 1240 Mill. It has become a problem because the one axis starts to move before the

finishes its move. This causes unwanted geometry in the work piece and other bad things. I was

wondering if I could reprogram the variable frequency drive to accelerate and decelerate faster without

hurting the machine. I have found the manual for the VFD (C300) online.

1. Attached is a document showing the correct parameter settings for the C300. Check these and correct

then as required. If correct the spindle acceleration should be quick enough to provide satisfactory

results.

2. To control the path following tolerance of axis movements include a block like:

G64P.005 at the beginning of the program. the .005 specifies the maximum deviation from the

programmed path that is allowable to maintain the programmed feed rate given the acceleration limits

of the machine. Adjust the P value to suit the part tolerance.

Specifications and Main Features