Weird thing happened with my Viper 200

[Danno]

Larry;
Something weird that has never happened before has me concerned !!
I was changing the tool in the spindle, and for no apparent reason, the Y axis decided to all of a sudden put full power to the servo and rammed the table against my limit.
Just before this happened, I had tripped the drive by bumping the Y-axis a little too fast with the keyboard ( I should know better), but this has happened before and I just reset the drive by unplugging the power to it.
I'm concerned as to why this would have happened. Luckly nothing crashed !!
Dan

[Larken]

Dan
I think you have a bad connection to the encoder, for a drive to run away.

You might want to check the cable connections to the encoder, and make sure the cable isn't pinched somethere in the machine.

Larry

[gPiplay]

if the encoder for the DC servo is bad, it is possible for the motor to running
out until hit the mechanical limit, be careful!

For the AC servo, like the ac servo using absolute encoder from DMM Tech,
if the encoder connection is bad, the rotor orientation of brushless motor
will be wrong, then the motor will sticked where it is, no running out absolutely.

[Al_The_Man]

Originally Posted by gPiplay if the encoder for the DC servo is bad, it is possible for the motor to running out until hit the mechanical limit, be careful! .

It does not matter what kind of servo or type of encoder feedback, it is up to the controller to detect that a position error exists and shut the drive off.
Whether the servo loop is closed back to the CNC control or an intelligent drive.
All the systems I use work this way.
Even in the event an encoder signal is missing.
Al.

[Larken]

It does not matter what kind of servo or type of encoder feedback, it is up to the controller to detect that a position error exists and shut the drive off.

All my Viper drives have this feature now (for about 6 months) that if the encoder is dead, the drive will shut down.

Dan's Viper is an older firmware version (but can be updated).

Yes an AC servo, Brushless and stepper can't run away if the drive fails, But
these mills are retrofits using the existing large DC servo's so replaceing the motor is usually out of the question.

Larry K

[tjs88yj]

Originally Posted by Larken All my Viper drives have this feature now (for about 6 months) that if the encoder is dead, the drive will shut down. Dan's Viper is an older firmware version (but can be updated). Larry K

I also have 3 of the older Viper 200 firmware version. What is involved in updating them?

Tom