On Sat, 2007-08-04 at 01:23 -0500, RogerN wrote: > ----- Original Message ----- > From: "Kirk Wallace" <[EMAIL PROTECTED]> > To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> > Sent: Friday, August 03, 2007 10:49 AM > Subject: [Emc-users] VFD Braking Resistor > > > > Hello Roger, > > > > I have been working on my lathe spindle VFD, so I have been following > > your messages. I got it mostly working last night, and during testing, ... snip > > braking on your setup? > > > > Kirk Wallace > > > > Unfortunately my drive takes more than a dynamic braking resistor, mine > requires a dynamic braking unit. When the DC bus voltage gets to high, ... snip > faults by limiting my decel rates. It's good to hear that the dynamic > braking resistor does the job. My drive had DC injection braking, have > you experimented with that? > > Thanks! > > Roger Neal
I figured you had a good reason for doing what you were doing. Now, I know what it is. The VFD's I have gotten so far, have had dynamic braking built in, so I don't know anything different. I am going to guess that DC injection braking is when, instead of letting the motor coast, the VFD invokes a reverse direction command for the duration of the deceleration, limited to the current and voltage limits of the normal drive circuit? I think in the long run, your work with using a PID loop with the spindle VFD will allow us VFD users to optimize the last bit of potential from these drives. Right now it seems like a balancing act between performance and setting limits that are safe but restrictive. 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 Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
