Questions and answers

What is the forward and reverse starter?

What is the forward and reverse starter?

A forward/reverse magnetic motor starter is constructed from two regular contactors installed with a mechanical interlock that prevents both coils from pulling in simultaneously.

What is reverse starter?

The Reversing Starter is a special type of push button starter wherein addition to starting/ stopping of motors the director of rotation of a three phase induction motor can be done by inter changing the connection of any two terminals of the supplies which is done through two separate contactors, one for forward and …

What is the purpose of interlocking in a forward reverse starter?

In the case of reversing starters, interlocking is used to prevent both contactors from being energized at the same time. This would result in two of the three phase lines being shorted together. Interlocking forces one contactor to be de-energized before the other one can be energized.

How many power contacts are needed for a forward reversing starter?

two sets
Forward / reverse starters will come with two sets of normally open auxiliary contacts to act as holding contacts in each direction. They will also come with two sets of normally closed auxiliary contacts to act as electrical interlocks.

What would happen if both contactors were energized at the same time?

What can happen if both coils are energized at the same time? The mechanical interlock only allows one armature to pull in which causes the other coil to draw a current of 4 to 10 times higher than it’s pulled-in value. This causes the coil to burn out. Between the operating coils of the contactors and L2.

How does a reverse starter configuration reverse the direction of a motor?

In order to reverse the direction of an AC motor, the magnetic fields must be altered to provoke movement in the opposite direction. Since each wire consists of a positive and negative current within the magnetic fields, the flip-flopping of main and starter wires causes the motor to run in reverse rotation.

Why is it necessary to interlock the star and delta contactors?

A normally close auxiliary contact from both star and delta contactors (5&6)are also placed opposite of both star and delta contactor coils, these interlock contacts serves as safety switches to prevent simultaneous activation of both star and delta contactor coils, so that one cannot be activated without the other …

Why interlocking is used for the contactors?

What is Contactor Interlocking? When an electrical circuit has two contactors and only one of them needs to be turned on at a time then the interlocking system is used. The interlocking system ensures that only one contactor can be on while another one will be in off condition even if we try to manually on.

What are the advantages of forward reverse motor operation circuit?

BENEFIT -: Forward Reverse starters are widely used due to their relatively low price. There are no limits to the number of times they can be operated. The components require very little space.

How do you make a single phase motor go forward and reverse?

To reverse rotation on a single phase capacitor start motor, you will need to reverse the polarity of the starter winding. This will cause the magnetic field to change directions, and the motor will follow. In order to achieve this, you can swap the connections on either end of the winding.

How do you make a electric motor go forward and reverse?

Remove power from the motor. Hook the battery positive wire to the negative terminal and hook the battery negative wire to the positive terminal for a simple DC motor. Install a double pole double throw changeover switch between the battery and the motor. The motor will now have a forward, reverse and an off position.