Newbie- Spindle Drive Fuse Size

[turbo jim]

I have a friend with a Tree Machine Tool model# VMC 3016, S/N# 9-15-92-1011. He has blown line side fuses for the spindle drive in the past. Since he has owned the machine it's had 15 amp fuses installed.

Since he has no manuals or electrical schematics I was wondering if anyone knew what the correct size fuse should be. The drive is a Yaskawa ( I think). There is a sticker on the drive that has CIMR MTIII-7.5k, and there is a parameter sheet attached to the drive that has a model# of VS-626MTIII.

The nameplate on the machine states 230VAC, Largest motor 30A, FLA 30A. The spindle motor looks to be the largest motor on the machine which would tell me the fuses are too small. Any help would be greatly appreciated.

[lavrgs]

My spindle drive is a General Numerics but I'd guess the fuses are similar. How often are fuses blowing? If it's just occasionally it's probably doing its job. Are the fuses in the spindle drive or are they in a separate box? I recall three fuses near the spindle drive on my recently dismantled machine...just checked they're MDX-2 which I believe is 2 amp 250V...so I'm guessing the one you're talking about is in or on the spindle drive and mine is 5Amp...so I don't think we're gonna solve this without someone with a Yaskwa piping in.

[underthetire]

15 seems small. Call yaskawa with the drive number, they can look it up. If it still blows fuses, sound like a bad transistor on the DC link.

[turbo jim]

The "3" fuses are in a fuse block ahead of the drive that supply 230 V power to the drive.
The fuses blow randomly, it depends on the type of tooling, material, and his feeds & speeds.
He uses surf cam for programming software. I'm not familiar with the software, but I would like to assume that it would take care of setting the proper feeds and speeds for the particular type of tooling and material being used.