leitmotif
Member
eddycheong said:thx for all the replies..1 more thing how can i change the motor direction..my friend told me he manage to reverse the 3 ph motor by change the hot wire connection to the inverters, but that is 3 ph motor
EDDY
On ANY motor you must change the rotation of the field relative to the armature to change rotation.
3 phase motor on "standard" 3 phase can be reversed by reversing any two motor leads. This changes phase rotation from ABC to BAC thus reversing motor. What happens in the motor is field A energized first (so to speak) then when you reconnected B energized first so that reversed the rotation of the field in the stator.
3 phase motor on VFD can be reversed by reversing any two motor leads OR telling VFD to change firing sequence of IGBTs thus changing phase rotation from ABC to BAC thus reversing motor.
DC motor can change rotation by reversing the armature or the field(s) possibly plural if a compound motor both series and shunt field. You cannot change rotation by reversing the line leads.
Single phase motor can be changed by reversing one of the two fields. The trick here is when wound the field leads must be brought out to the junction box. You cannot change rotation by reversing the line leads.
Dan Bentler