motor feedback

[Ali 0]

dear all, i have seen in the programs,,,as motor run feedbach,motor trip feedback and overload feedback.....my query is from where in the field we take this feedbacks from.i mean wiring...

[Gamble 0]

These are usually auxiliary contacts from your motor controlling device (motor starter, VFD, or softstart).

[Leitmotif 0]

Regardless of the terms used in stuff you read I think the important thing is to understand what you want the machine to do and design based on your "you do this" cirteria. From simple to complicated MOTOR RUN can be done with a contact on main starter relay. In case of VFD this would be a contact in the VFD - MOTOR TRIP (fault) can be done with contact on sensor ie overload, winding temp switch etc. In case of VFD you can use a contact there. EXCEPTION - where multiple motors are powered from one VFD - in that case each motor has individual relays with overload protection so this should be monitored by PLC in my mind. MOTOR RUN and it is actally doing something - ie the pump is actually pumping water - use flow switch flow sensor or pressure switch. MOTOR SPEED can get complicated depending on what you are doing. can be done by tach generator or encoder MOTOR (or load) position can be done by encoder for very fine positioning or limit switches if you have a wider tolerance on position. MOTOR DIRECTION can be gotten from the contactors (simple) to reversal of tach generator output voltage to using encoder. Dan Bentler Edited 12 Nov 2010 by Leitmotif