Servo inertia calculations

[fer_mayrl]

Hello guys,
I was looking over at the sureservo manual (automation direct servos) and on a sample calculation it states that the ratio between the load inertia, and the motor's inertia should be kept less than 10.

Does anyone know why is this? and does it apply to steppers too?

Regards
Fernando

[Chaoticone]

Hey Fernando,
    I have read that some where about steppers also. I can't remember where though. It might have been in the building a router section of this forum. I think it may have been by Art in the beginning of that section. If not there it might have been on Bob Cambels site?   My memory isn't what it use to be.

Brett

[Chaoticone]

http://www.machsupport.com/forum/index.php?topic=1530.0

This may be the one I was thinking of. If not, it will be in the same board.

[fer_mayrl]

I found this document from oriental motor, it states some guidelines of the inertia ratio, but i think it doesnt say why it is needed

[Chaoticone]

Here is a link to a free software download the Automation Direct offers to help in the decision.

http://www.sureservo.com/downloads.htm

Brett