On 03/05/2017 07:38 AM, Ben Potter wrote: > Interesting - I have to admit I'm still a little bit > confused as to how these drives work, running 360V AC to > the chokes and somehow turning that into 140V DC seems... odd. Well, does it run off 3 Phase power? If not, then it gets hard to drive motors with any constant torque or speed. Phase angle control from a 3-phase source takes 6 SCRs, and due to the overlapping waveforms of the 3-phase mains, can give fairly steady power to the motor. Still, the servo bandwidth will be pretty low.
With single-phase power, the bandwidth will be really low to avoid the 120 Hz pulsing from driving everything crazy. it seems a bit odd that a signal capacitor caused the failure, but maybe that fouled up the current control logic to get the SCRs turned on in the wrong sequence. Jon ------------------------------------------------------------------------------ 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
