CAD CAM EDM DRO - Yahoo Group Archive

Re: [CAD_CAM_EDM_DRO] Servo motor cabling....

Posted by Jon Elson
on 2002-05-23 21:22:04 UTC
doug98105 wrote:

> Group,
>
> I don't recall seeing any discussion of cabling for your servos.
> What have you guys done for this?
>
> Last time I had to buy an oilproof cable with Amphenol connectors for
> one of my mills I was set back close to 200 bucks. Times 3 or 4 and
> that's a substantial outlay. So how are you getting around this
> expense?

I just used whatever cables I could find at the local electronics shop.
I used a shielded twisted pair cable for my DC tachometers, this is
pretty common audio cable. I used an individually shielded 4-pair
cable for the encoders (AB and Z, plus power.) Both of these cables
were standard, grey PVC sound mixing board type of cable. For the
motors, I got some nice rubber-like 4-conductor cable, that may
be an oil-resistant type, I don't know for sure. As I have output
filters in my servo amps, I didn't need to shield this cable. Some other
servo amps or drivers might need shielded cables here to prevent
RF radiation or interference with encoders, etc. So, I have 3 cables
per axis. I have no connectors on the motor/encoder end, and use
a 29 (I think) pin AMP plastic circular connector. I still haven't
gotten the limit and home switches wired up (mostly, the mechanical
part of this setup is holding it back.) But, that will eventually require
a 4th cable per axis. That's why I have so many pins on those
connectors. In over 3 years of operation, I have seen no deterioration
of these cables, due to oils, coolants or flexing. I made the loops of
wire large to spread the flexing of the cable over a wider radius.
These ARE all stranded cables, of course.

>
> Also, is there any kind of industry standard on the pinouts for
> servos? Two machines I checked have 14 pin connectors, but different
> sized ends. I notice my controller box for a servo 4th axis has a 14
> pin output connector too. Is this a coincidence or is 14 the
> industry standard?

No standard whatsoever that I know of. Now, specific manufacturers,
like AB, Yaskawa, Toshiba, etc. have their own standards, but generally
one series of motors will have different connectors than another series
from the same manufacturer.

Jon

Discussion Thread

doug98105 2002-05-22 22:37:51 UTC Servo motor cabling.... Jon Elson 2002-05-23 21:22:04 UTC Re: [CAD_CAM_EDM_DRO] Servo motor cabling....