Fanuc dc servo with Pulse coder 2000 feedback

[Harryp]

If I am right DC's don't hold a lockup alignment right? I was looking to disassemble the motor but am scared to screw up any alignment. The motor has a pulse coder 2000 on it. I will attach some pictures below. Please advise as to what steps I should take before going ahead and opening this thing. I know it just needs a seal change.

[Al_The_Man]

Not sure of your questions or concerns, it looks like a DC motor off a 6T/M ?
The encoder does not require alignment etc, the only thing you probably will affect is if any grid shift is entered and may need correction depending on the axis, if the encoder is removed.
Al.

[Karl_T]

My mill uses DC brushed servos and has that exact same encoder. The machine will re-find itself after you're done by homing. it is possible to put the encoder in 180 degrees different and that would move your home by 1/2 a screw revoltuion. there's only two ways - you could mark your home and if its off, rotate the encoder 180 and reinstall.

Don't drop that special little encoder coupling and let it roll under the machine. You won't find it for hours. DAMHIKT

Am I answering your question?

[Al_The_Man]

Originally Posted by Karl_T The machine will re-find itself after you're done by homing. it is possible to put the encoder in 180 degrees different and that would move your home by 1/2 a screw revoltuion. there's only two ways - you could mark your home and if its off, rotate the encoder 180 and reinstall.

Also the grid shift parameter would take care of it.
Al.

[Harryp]

Thanks this answers my question, but what I wanted to ask in addition is that. By nature DC servos dont have a lockup angle set on their feedbacks.. am I correct?

[Al_The_Man]

Originally Posted by Harryp By nature DC servos dont have a lockup angle set on their feedbacks.. am I correct?

Not sure what you mean by 'Lock up Angle'?
Al.

[mike_Kilroy]

sounds like you are asking about brushless DC rotor-to-stator alignment requirement. Known as phase angle. If this is what you mean, then you are correct, no, there is nothing like that with DC motor. As you say, 'by their nature.' Reason is the commutator & brushes do this alignment as the rotor rotates.