Re: err/res circuit(updated picture)

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "cnchomeman"
<cnchomeman@y...> wrote:

>
>
> here is the new picture of what I want to do.
>
> http://www.e-zflight.com/files/ncnczi.jpg
>
> Eric
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "cnchomeman"
> <cnchomeman@y...> wrote:
> > Have a look at this circuit for the err/res of 3 drives. Ignore
> the
> > 3 contacts from the fault relays in the estop rung. I will move
> > those and a contact from the esr to a new rung with another
> > relay/contact going to the computer input. As drawn, a fault

would

> > shut down all power to the drives. Other than that, does it look
> ok?

A preliminary look confirms it will probably do what you want. Me
thinks there must be an easier way to do it though with fewer parts.
Seems that I remember the err/res is a high impedence input and you
can tie all three of the axis's together and build one control that
does the same as the three relays.

Lets think about this: If you tied the three err/res pins together
(provided all three axis DC feeds share the same ground) then if any
one of them went into fault it would shut down the other two. A PNP
Transistor driving a fault relay powered from the Gecko +5 (make sure
you use a flyback diode across the relay coil with cathode to the +
side of the coil) then the NO relay switch contacts could be used to
trigger e-stop. I believe that the newer 320/340's will auto reset
if the fault condition is cleared but if not, you could use a
separate relay or an opto (NPN type) with the collector tied to +5
and the Emitter to the err/res common connections. Activating the
opto would put a logic high on the err/res pins and reset all three
Gecko's Your 6 second timer could be an NPN transistor that is
controlled by a 6 second one-shot (555 timer?).

To review. All three Gecko err/res pins tied together. A PNP with
the base tied to the common junction the collector to ground and the
emitter to either a relay coil or the cathode of the input of an Opto
isolator to provide a signal back to the PC for e-stop.

For reset, a 6 second "one-shot" circuit driving either another relay
or the input of an opto and the relay contacts or opto NPN providing
the +5 from the Gecko to the common junction to reset all three.

Anybody see anything wrong with this idea? Mariss?

For the e-stop side of things you need to consider cutting the DC
power to the motors (Gecko's) by opening the DC side of the circuit
AFTER the filter cap. While turning off the AC will eventually shut
things down the filter cap will continue to supply DC power for a
couple of (maybe critical) seconds. I have a large contactor (4pole)
that uses one set of its own contacts to "latch" itself on. I have
the table limit switches wired in a normally closed configuration
going to the coil of a 12VDC relay. The contacts of this relay are
in series with the large contactor coil (as is the STOP) button on
the front panel and the PANIC button on the machine. All of these
use the Normally Closed contacts so a switch activation removes power
from the contactor coil. Anything that breaks the circuit to either
the 12VDC relay coil OR the contactor Coil shuts off DC power
immediately.

I have a schematic tha I will be glad to send you.

Tom