Re: isolation, current and velocity, encoders

Jon--

One version of this amp is rated 6/15 amps and the other 15/30. The
full PN's are like 12 alphanum chars and differ only by a
transposition in the middle. I've actually got the 15/30 version.
Thanks for the advice about sizing and fusing re isolation
transformers; doubtless the price of these things increases
geometrically w/ kVA rating.

Too bad about tach and encoder both. My reverie was nice, cheap,
plain old, single shaft end PMDC motors with an encoder on the other
end of the screw. Like the 1/2 HP 90 VDC 1750 RPM's so common on
ebay. Things just start getting pricey when you're looking for
a "real" servo motor or a motor with double shafts.

Assuming it's OK to put the encoder right on the screw (and you did,
right--the SumTak's?) maybe a fellow who knew what he was doing could
rig non-contact optical tachs pointed at the motor shafts. Dan M. has
kind of broken the price barrier on these things ...

--Jack

--- In CAD_CAM_EDM_DRO@egroups.com, Jon Elson <jmelson@a...> wrote:
> > Well, OK; I guess I'll go hunt down a 4.5kVA isolation
transformer;
> > it would seem that "ungrounded AC power source" is the key here.
>
> Well, this will be overkill, I'm sure. Besides, I think your amps
were
> only 6 or 7 continuous amps - or am I confusing two different
people?
> It would be a rare condition that all servo amps were delivering
full
> continuous power all the time. Just put in a slow-blow fuse rated
> for the full transformer rating. I think a transformer rated at 1/2
> this size should be fine for most home machines. A high speed
router
> that was run in commercial service might be a different story.
>
> Jon