On Wednesday 10 February 2021 09:11:58 Todd Zuercher wrote: > On the Fanuc machines I work with a servo amp fault is very similar to > an e-stop condition, only worse. In E-stop power is not removed from > the spindle VFD, the servos are disabled (I don't think power is > removed from them), and the VFD is sent an e-stop signal and brakes to > a stop (actually the VFD has an input that monitors the estop chain). > The control and all logic circuits remain fully powered and any axis > brakes (such as for the Z axis) are engaged. The effect of a servo > fault is essentially the same except the entire machine must be power > cycled at the main disconnect to clear the servo fault (simply power > cycling at the control is not enough.) Where clearing an e-stop only > requires resetting the e-stop and pressing the reset button. Part of > why I believe power is not removed from the servos at e-stop is the > fact that a tiny power blink on one or all phases will usually cause > the servos to set an alarm that requires cycling the power to reset. > This is the same for multiple machine models from 3 different large > manufacturers. > > Todd Zuercher > P. Graham Dunn Inc. > 630 Henry Street > Dalton, Ohio 44618 > Phone: (330)828-2105ext. 2031
I'd call that a major PITA Todd. The inrush from turning it back on likely accounts for 90% of the parts failures those controls suffer. What the hell were they thinking? More income from selling replacement boards? Stuff with larger inrushes gets soft-started here, so that inrush is slowed some by a high powered resistor of 50 ohms or so in series with the line power for the first 3 or 4 seconds. IMO thats a powerfull contribution to not having any parts failures. The GO704 with its huge spindle supply, draws about 3 amps working the average job. Tutn it on with a normal swich and you will useally hear a 30 amp breaker fall. But I've only a 20 in that slot for the last 5 years, tripped once when I plugged a 1500 watt heater into that circuit. No repeats since turning the heater down to the 700 watt coil only. > -----Original Message----- > From: John Dammeyer <jo...@autoartisans.com> > Sent: Wednesday, February 10, 2021 12:09 AM > To: 'Enhanced Machine Controller (EMC)' > <emc-users@lists.sourceforge.net> Subject: [Emc-users] Dealing with > Servo Faults > > [EXTERNAL EMAIL] Be sure links are safe. > > Quick question. > > There's a multi-axis operation in progress. For whatever reason one > of the servos throws out a fault and of course stops. > > Should just the enables to the other servo drives be removed or should > power be cut to all drives. > > I'm not really in favour of dropping out power because that would mean > you also lose the ability to easily recover. The other drives and > spindle were working so you really just want them stopped and things > like coolant shut off. > > This isn't the same as an ESTOP which does remove all power that could > result in motion. Low voltage control and PC are left running. > > For my PMDX-126 BoB my faults are consolidated and brings the PMDX > /FAULT input low. That disables the ChargePump which in turn disables > all outputs including the enable to all the drive. And the orange > button beside the red one on the user screen goes greyed out. > > After 4 seconds the /FAULT input is once again brought high (inactive) > and now the orange ENABLE button on the screen (or F2) can be clicked > which then asserts the ENABLE output to the drives and allows hardware > to be controlled again. > > For my servos taking the ENABLE signal FALSE and then TRUE resets the > FAULT condition. If the fault is still there then the /FAULT is > brought low again. Etc... > > What do other systems (including commercial) do when a drive faults on > one axis. > > John > > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
