thats true, but its not like that vfd is old or anything, id think that with a
braking resistor, or even the built in one, that there wouldnt be 2 much
latency. I plan on setting up emc to control speeds and reverse and all that
but im going to remount that front panel on the vfd for manual control without
havin to touch emc. I have that same vfd, Good pick!
Kirk Wallace <[EMAIL PROTECTED]> wrote: On Mon, 2008-01-21 at 08:47 -0800, Rob
White wrote:
> u prolly want the vfd to be master because it has hardware failsafes
> builtin, I have the same vfd and i would not loose that front face
> plate. Use the modbus under the cover, read teh manual and get back to
> me with ur findings please.
You have gotten me to thinking. Modbus can have quite a bit of latency,
so I don't know if I would want to rely on it for e-stop class
functions. I would think having the VFD alarm relay output in the e-stop
chain would be appropriate. That would leave Modbus open for non-real
time commands and information. I was thinking of using it for setting
speed and direction, but the more I think about it, the latency issue
may be a problem here too. At this point, I would have EMC be the master
and poll the VFD for performance and trend information, put the alarm
output in the e-stop circuit and a DAC and opto-couplers on the normal
VFD control inputs (analog speed, forward, reverse). Although, I could
change my mind, or I mean, update the spec, at any time.
--
Kirk Wallace (California, USA
http://www.wallacecompany.com/machine_shop/
Hardinge HNC lathe,
Bridgeport mill conversion, doing XY now,
Zubal lathe conversion pending)
-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/
_______________________________________________
Emc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-users
---------------------------------
Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now.-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/
_______________________________________________
Emc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-users
