How to Define a Synchronous Motor
- 1). Locate the nameplate on the side of the motor. This contains important data that will be used to define the synchronous motor speed, such as design specifications and other certain technical information. It will also have the manufacturer's name and address (Reference 3).
- 2). Write down the number of magnetic poles used in the synchronous motor. This number can be found on the nameplate under the design specifications. Spinning rotors inside the motor along with other internal magnets provide anywhere from 2, 4, 6 or 8 magnetic poles (Reference 3), or possibly even more. Rotating magnets supply energy to the synchronous motor, so a key factor in determining synchronous speed is by the number of magnetic poles.
- 3). Write down the operating frequency (Reference 3), or the amount of electricity used to power the engine, usually stated in Hertz (Hz). Find this information in the technical data section on the nameplate.
- 4). Multiply the operating frequency by the constant, 120 (Reference 3). For example, suppose we have a hypothetical motor that runs at 60 Hz, you would multiply 60 by 120, for a total of 7200.
- 5). Divide 7200 by the number of poles in the motor (Reference 3). For example, suppose our hypothetical motor running at 60 Hz has 6 magnetic poles, you would divide 7200 by 6, for a synchronous speed of 1200, meaning this particular engine is defined as a 1200-RPM synchronous motor.
