[cncuser1]

I am hoping to get a poll of peoples experiences putting closed loop steppers on a Sieg X2 mill.
?

Can you summarize what you have done,your recommendations and what are your lessons learnt?

[CS900]

well I certainly don't use them on an X2, but I have been using closed loop steppers on my RF45 for many years now.

Pros:
- no tuning, plug them in and they work
- positioning error alarms. I have mine wired so that if any steps are lost on any axis it throws an estop and will likely save your part from being ruined. It's saved me a few times.

cons:
- a little pricey and dated verses some of the AC or DC servos available today.
- position feedback comes off the motor itself and will not account for backlash in your system.


overall, they are significantly better than regular steppers, but if you have the money i'd go right to some clearpath or DMM motors.

[cncuser1]

CS900 I'm looking at the closed loop steppers because they are economical and the next step up in accuracy from my current open loop steppers.

Which configuration do you use and why ( drivers local to the motor or remote)? I don't see a difference in the specs, is there one?

[CS900]

Mine are remote drivers. They were the only kind available when I bought them.

I wouldn't expect to see any increase in accuracy, they have the same number of steps/rev as regular steppers, but you will be able to know when you've lost steps.

as far as specs, the motor torque and speed will be exactly the same as a similarly rated open-loop stepper.

[cncuser1]

CS900: So your remote drivers can tell you when you've lost steps but the drivers local to the steppers don't have that functionality.

That is noteworthy, thanks.

[pippin88]

That's not what CS900 said.

[cncuser1]

pippin88: Where did I make a mistake?

[pippin88]

CS900 did not say anything about the difference between separate (remote) drivers and drivers attached to the steppers. (CS900 said the only ones available when they bought were the separate drivers).

I would expect all closed loop steppers to have a fault output to signal to the controller when steps have been lost.

[CS900]

that is correct. I believe most all close loop systems have an error output signal in one form or another.