Kirk Wallace wrote: >My VFD has an RS-485 serial port where the control panel plugs in. >Apparently you can mount the panel remotely or connect the port to some >other Modbus host. I will be using the VFD for spindle control which I >am guessing is in userspace? The approved connection method of using the >digital and analog inputs should work just fine, but I thought if Modbus >were available, that would be even better. I am a little concerned about >electrical noise with routing the 0 to 10 V speed signal across the >width of the lathe, but I shouldn't try to fix what isn't broken yet. > > OK. Serial should be easier for RT, but I think userspace may be OK for spindle control anyway.
I suspect that the VFD has a lot of filtering on the analog speed input. The motor can't respond to rapid changes, so no point making that input high bandwidth - I'd be surprised if the filter frequency is higher than 10 Hz. Remember - the VFD is designed to be used inside a noisy control cabinet :) - Steve >Kirk Wallace >~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >On Tue, 2007-07-31 at 18:45 -0400, Stephen Wille Padnos wrote: > > >>Well, yes and no :) >> >>Modbus has been discussed, and I think Matt Shaver did some work on >>getting a VFD to work with EMC2. I'll be doing something similar to >>talk to a PLC in the next month or so. I'm not sure that I'll be able >>to make the driver work in realtime though - it may end up being >>userspace. I think I'll be using a serial port, but if I end up needing >>ethernet, it'll almost certainly be userspace. This driver work won't >>be specifically useful for the EMC crowd, but it should be able to >>provide a basis for something that is. >> >>Is your VFD serial, ethernet, or something else? >> >>- Steve >> >>Kirk Wallace wrote: >> >> >>>I just got a VFD with a Modbus port. Is there a plan on getting EMC to >>>use Modbus? Thanks. >>> >>>Kirk Wallace >>> ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
