[colton_m]

Hello,

I have encountered a very bizzare problem with one of our lathes, hopefully someone has experienced this before and has an idea of what I could check.

The machine is an SL-20 new april 2007.

Today while running a program that has been running for 4 days with no problems the spindle slowed down and stopped in the middle of a finishing pass and the control is reading 200% on the spindle load.

I restarted the machine and started it at 2000rpm in MDI. It starts, speeds up like normal then over 10 seconds or so it slows down to zero rpm and again is reading 200% spindle load.

The belts look good, and the sindle can be turned by hand freely once it has come to a stop. No obstructions.

I also have discovered that this problem does not occur below 1300rpm. 1299 runs fine, but when it hits 1300 the load jumps to 200% and it slows down to zero rpm over a span of about 10 seconds.

Any ideas?

Thanks

[underthetire]

First guess would be a feedback issue/bad encoder, second would be the spindle amplifier going south.

[haastec]

Does this machine have Delta-Wye switching? If I recall correctly 1300 is about the where the switch would occur.

[colton_m]

Does this machine have Delta-Wye switching? If I recall correctly 1300 is about the where the switch would occur.

I am not sure, do you know how I could find that out?
If so that would make sense as to why it drops off at 1300rpm, what needs to be changed to fix such a problem?

Thanks

[Ydna]

It's a relay located in the electrical enclosure that switches the wiring when crossing up/down through a certain speed. You can write a looping MDI program that cycles spindle speeds and run it with the enclosure door open, probably be easy to find the relay that way.
If it's the cause then Haas might sell the part to you, it wouldn't take much to switch it over.

[wdomhart]

+1 on the Delta-Wye contactor. Press the [Param/DGNOS] Display Button to bring up the Diagnostic Screen. Use the right arrow key to move over to the I/O tab. On the Outputs 1 side of the screen at the bottom should be an output called "Spindle D:Y". Observe this bit while running the spindle. Run a program that moves the spindle speed from 1000 RPM to 2000 RPM and see if the "Spindle D:Y" output changes from 0 to 1. Additionally, see if that coincides with the spindle stopping.

Let me know what you find.

Will