On 03/04/2017 08:33 AM, Ben Potter wrote: > Good afternoon, > > > > I've got a converted Bridgeport Interact which decided to give up the ghost > last week. I think that one of the servo drives/amps is dead, and am hoping > that someone can sanity check my troubleshooting before I start spending > money. > > Before I removed any wires, I checked the wire numbers against the schematic > and put everything back in the same place. > > > > Fault: > > On power on, blows fuse/breaker. > > > > Diagnostic: > > 1: Remove power + HV bus from X, Y, Z drives > > Powered up, no axis movement possible > > 2: Connected power + HV bus from X drive > > Powered up, X movement OK > > 3: Connected power + HV bus from Y drive > > Powered up, X + Y movement OK > > 4: Connected power + HV bus from Z drive > > Blew fuse > > 5: Removed X drive, put Z drive in place of X > > On power up X motor ran at maximum speed until I hit e-stop > > 6: Put Z drive back in place, replaced X drive. Disconnected motor > connection only from Z drive > > On power up X and Y movement OK. > > 7: Reconnected Z motor to Z drive > > On power up Z ran at maximum speed until I hit e-stop > > > > I'm pretty sure that the Z drive is dead - can anyone suggest any other > tests I should do? > > > > Thanks > Ben > Hi Ben,
Andy's comment may be spot on. If you lost the tach then the drive really is much harder to tune. Hook the servo motor to 12 vdc and it should move smoothly. Reverse polarity and it should go in the opposite direction. Assuming it has a tach ... monitor the tach output and it should be the same voltage but opposite polarity when you reverse direction. Now hook up servo amp but short the analog input before you power up. On power up it should move slowly or not at all if it is well nulled. If the tach input is reversed than the drive is getting inverse velocity feedback and will move a max speed to end of travel/estop. In these kind of situations it is handy to have a battery box, i.e. something like a 9 v battery with a pot to adjust the output voltage and a switch to flip the output polarity. Makes for a quick sanity check. Lacking a battery box just try a 1.5 v flashlight cell across the analog input. Hope this helps with out adding confusion. Dave ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
