If a three phase motor in running in reverse, then one of the phases is reversed, plain and simple. If the wiring is correct at the motor, perhaps the phase reversal occurred someplace else.
If you mean to reverse the direction of a three phase motor, you just switch any 2 leads. switch 1 and 2, or 2 and 3, or 3 and 1.
motor is designed to operate in forward and reverse direction for the purpose of elevator. Phase sequence protection is not required.
To reverse direction, swap any two hot wires.
A single phase induction motor has two sets of coils and a centrifugal start switch. The start winding is in series with the start switch. The start winding provides a rotating magnetic field in one direction enabling the motor to start. The motor can be reversed by reversing the connections of either the start winding or the run winding but not both.
by changin the freq usin an IGBT.
three-phase motor: Swap the connections of any two phases to the motor.single-phase motor: Usually this can be achieved by reconnecting the starting capacitor from one motor winding to another.Another AnswerAs you have no access to the motor's phases, you must interchange any two of the three line conductors.
You would reverse rotation on a 3 phase motor to get it to run backwards. Say I fill up a tank truck from a lake. I turn on my generator. I run the motor in one direction. Then I drive the tank truck and the motor to a different location. Then I turn on my generator. I attach the hose to the motor on tank truck. I throw the switch to make the motor run backwards. I aim the hose at the fire in your house. Aren't you glad that I can make my 3 phase motor run backwards?
Then it is not a three phase motor.
There are two alternate methods depending on whether the motor is single phase or three phase. On a single phase motor, reverse either the start winding coil lead or the run winding coil lead but not both. This action will reverse the motor's rotation. On a three phase motor, interchanging any two of the three coil leads will reverse the motor's rotation.
If a three phase motor loses one leg it will do neither of what you suggest. To change the rotation of a three phase motor any two motor leads must be interchanged. When one leg of a three phase system goes down it is said to be single phasing. The overload protection on the motor senses the higher current on the other two legs and trips the overload heaters. This in turn drops the contactor open and disconnects the motor from the supply.
Your question is confusing. Are you asking how to reverse the direction of a three-phase motor? If so, then the answer is that you simply interchange any two of the line conductors. This will cause the naturally-rotating magnetic field in the motor's air gap to reverse direction, causing the rotor to reverse direction.
Switch two of the three wires.