[BJP]

Hello,
We have the following alarm on our Toyoda FA450 Horizontal Mill:
"OT331 Motor Lock V-Sig Los" - Fanuc 15M controls.

Also, when the spindle clamps the tool, it isn't grasping the tool tightly. I can still pull it out almost all the way by hand.

....any ideas what's causing this alarm? I didn't see a description for it in the manuals.

[ifixcnc]

It sounds like you have two problems. The tool loose in the spindle sounds mechanical, and dangerous. Before running get that fixxed. The V signal loss, sounds like a drive problem and should be described in a Fanuc manual.

[RAC]

Is this a Fanuc spindle? If so you might want to have a look at the BZ sensor in the back of the spindle, it sends speed and 1st rotation signals to the drive. As for the clamp issue, can you look at the collet without a tool in the spindle to verify what is happening in there?