Pairs of Poles | Synchronous RPM | Actual RPM |
---|---|---|

1 | 3600 | 3492–3420 |

2 | 1800 | 1746–1710 |

3 | 1200 | 1164–1140 |

4 | 900 |
873–855 |

## What is the speed of a 4 pole 50hz synchronous machine?

The synchronous speed of 4 pole, 50 Hz Induction Motor is: **750 RPM**.

## What is synchronous speed of motor?

The synchronous speed is **the speed of the revolution of the magnetic field in the stator winding of the motor**. It is the speed at which the electromotive force is produced by the alternating machine. A machine that runs at synchronous speed is called a synchronous machine. …

## Is a 2 pole motor faster than a 4 pole motor?

The number of poles has an inverse relationship with speed, i.e. more the number of poles less will be the speed of the motor. So, a **2 pole motor has more speed than a 4 pole motor**. But, for heavy power, 4 pole motor is best than 2 pole motor. Gearbox below 3000rpm is always required for a 2 pole motor.

## How do you tell if a motor is 2 pole or 4 pole?

A 2 pole motor is cylindrical in shape. The 4 pole motor is not cylindrical. A **2 pole motor has more revolution per minute**. A 4 pole motor has less revolution per minute.

## What is 120 in motor speed formula?

The equation for calculating synchronous speed is: **S = 120 f/P speed = constant (120) times frequency of power source (60 Hz) divided by number of poles used in the motor (P)**.

## Can we increase the RPM of motor?

**Yes**, but with a small amount above the maximum speed under normal rated conditions. Increasing the speed can be achieved by increasing the supply frequency as the speed and frequency are directly proportional; however, there are two constraints.

## What is a 4 pole 3 phase motor?

. For example, for a four-pole, three-phase motor, = 4 and = 1,500 RPM (for = 50 Hz) and 1,800 RPM (for. = 60 Hz) synchronous speed. The number of magnetic poles, , is equal to the number of coil groups **per phase**.

## How many coils does a 6 pole motor have?

To create a six pole motor use **six coils per phase** that creates three north poles and three south poles and so on. The number of stator slots is always a multiple of six. When it comes to the pole number it’s always a multiple of two because the north and the South Pole always come in pairs.

## Why does the synchronous motor run at synchronous speed?

This property is due to **the inertia of the rotor**; it cannot instantly follow the rotation of the magnetic field of the stator. Once the rotor nears the synchronous speed, the field winding is excited, and the motor pulls into synchronization.