When choosing a electric motor for a credit card applicatoin, a primary consideration is the speed range it will be operated in. Whenever a motor is run considerably slower than its rated base speed, numerous potential adverse effects will come into play, including reduced cooling efficiency, reduced power performance and a alter in the motor’s velocity and torque characteristics. To mitigate this issue, some motors and velocity controllers have been designed especially to operate a vehicle a load at low speeds with specific control.
Most domestic and industrial motor applications use 3-phase asynchronous induction motors, which operate 
at a speed that is determined by the frequency of the supply power. When an application operates at a continuous speed, the thing that is required may be a gearbox or quickness reducer that brings the motor speed down to the required level. Nevertheless, many applications require the speed of the electric motor to be various during operation.
This is normally achieved using a VFD or Adjustable Frequency Drive, which controls the speed by modifying the frequency fed to the motor. Deciding on the best motor and VFD type depends on a variety of factors, however, it’s important to initial look at the way the characteristics of a electric motor change when the velocity is reduced.
A motor usually has a base speed, specific by the manufacturer, that it is definitely made to operate at. However, if a engine is managed below the bottom speed, it may experience reduced effectiveness of the cooling system. Especially with commonly used Totally Enclosed Lover Cooled (TEFC) and ODP (Open Drip Proof) motors, where the cooling program consists primarily of a shaft-mounted lover, a reduction in speed results in decreased airflow over the engine and lack of cooling, and warmth buildup occurs. Particularly when the electric motor is operated with full torque at low speeds, heat can easily build up inside the motor to harming levels.
Gearboxes and quickness reducers are mechanical speed reduction equipment used in automation control systems.
speed reducer gearbox details and also misconceptions.