Question

A 208 V, 10 hp, four-pole, 60 Hz induction motor, connected in Y, has a full load slip of 5%.

b) What is the synchronous speed of the motor?

Answer 1

The synchronous speed of a 208 V, 10 hp, four-pole, 60 Hz induction motor is calculated using the formula (120 × frequency) / number of poles, which results in 1800 RPM.

Step-by-step explanation:

To find the synchronous speed of the motor, we use the formula for synchronous speed which is given by:

Ns = (120 × f) / P

where:

• Ns is the synchronous speed in revolutions per minute (RPM),
• f is the frequency of the supply in Hertz (Hz), and
• P is the number of poles of the motor.

Given a four-pole motor with a power supply frequency of 60 Hz, we can calculate the synchronous speed as follows:

Ns = (120 × 60) / 4 = 7200 / 4 = 1800 RPM

So, the synchronous speed of this induction motor is 1800 RPM.