Spindle stopped during cut... xyz continues to move. No overload estop protection?

1

I had a bit of a warped piece and it started hogging out a bit much, and it seems the VFD kicked out, but the axis movement continued. I know on my cnc mill if I stall the spindle I have the VFD connected through the estop to stop everything dead in its tracks, anyone familiar with the stock VFD that came with the 3hp spindle and if this is possible? Haven’t dug into it yet, but if there is overload detection on the VFD it seems that the machine should stop as well.

2

You’d think so, right? From my understanding, there is no native capacity, as delivered. If not, I’d like to hear why not.

3

I have been using this for a few years.
Follow the How to Set Delta VFD Parameters section and set the following initial settings:

Initial Over-Torque Detection Parameters

3HP and 4HP Avid CNC Spindle

Parameter New Value
06-03 2
06-04 105
06-05 0.1

8.7HP Avid CNC Spindle

Fine tuning the over-torque detection can be done by adjusting parameter 06-04 for 3HP and 4HP Avid CNC Spindles, or parameter 06-07 for 8.7HP Avid CNC Spindles.

4

So setting the over torque limits on is fine, but will it cause an error to occur and stop motion? I see that the output relay on the VFD is set to detect any fault ( setting 3.0 is set to 8) and is plumbed into the input signal on from the ESS on 2/12 , but not sure where in Mach 4 that is used to stop the machine, but just looked at it briefly this morning but need to go read up on Mach 4.

5

Yes, this will essentially cause an Estop when it trips. As Brian said, you need to do a little tuning possibly. I started out with 105 for the 06-04 parameter (which means 105% of full output capacity) for my 4 hp spindle. That tripped just a bit too easily (it even went off once while loading a big on my Rapid Change ATC). I moved it up to 115, and haven’t had a false trip again, but I also have not verified how easily it will trip on an overload. Basically, you want it to Estop before your spindle actually stalls, that way you won’t be trying to push through any material with no tool rotation.