John Figie But if it overshoots the > commanded position and goes into reverse to bring the motor back by more > than a 1 or 2 % drive while the motor is still coasting fwd, it will > crowbar the psu, getting it hot instantly, causeing the psu to do a shut > down until it has cooled for 2 or 3 minutes. Even then, no heat in the > BTS IC's. >
So if the motor is rotating forward and has enough inertia then when you try to slow it or reverse it it will become a generator and try to increase the output voltage on the PSU. Is the crowbar circuit in the PSU an overvoltage protection crowbar? If so, then maybe that is the issue. Maybe you need some way to get rid of the stopping energy with a shunt resistor and switch that activates before the crowbar trips. In industrial motion systems a shunt resistor and switch is used to regulate the DC bus that feeds all of the servo axis. This is not a precise voltage regulator, it just turns on the shunt as the voltage gets above a set limit and then turns off again as the voltage returns to a lower limit. Regards, 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
