Re: [CAD_CAM_EDM_DRO] Is this servo usable for position control?

grantfair2001 wrote:

> I have 3 Japan Servo DC servomotors, which were replacements for Zerox
> copy machine parts, now surplused.
>
> Detailed information about this motor is available at C&H:
>
> http://www.aaaim.com/cgi-local/shop991/shop.pl/SID=262414781538/page=D
> CME.htm#DCM8757
>
> This DC servo motor has a tach output, but no encoder per se. Motor
> speed is controlled by pulse width. If I count the tach pulses can I
> use this to establish positions reliably? And control this
> position with the 24 volts DC supply?

If the tach only has one channel, then you can't determine which way the
motor is going. If that is so, it is not suitable for positioning use. Are
these
brush motors or brushless DC. If 2-wire brushless DC, then itwill only turn

one direction, so that is also useless for positioning (unless you never
want
to go back to where you started from).

Jon