When choosing a engine for an application, a primary consideration is the speed range it’ll be speed reducer gearbox operated in. When a motor is run considerably slower than its rated base speed, numerous potential adverse effects will come into perform, including reduced cooling performance, reduced power efficiency and a change in the motor’s acceleration and torque features. To mitigate this issue, some motors and velocity controllers have already been designed especially to drive lots at low speeds with exact control.
Most domestic and commercial motor applications use 3-phase asynchronous induction motors, which operate at a speed that’s determined by the frequency of the supply power. When a credit card applicatoin operates at a constant speed, the only thing that is needed may be a gearbox or rate reducer that brings the motor speed down to the mandatory level. However, many applications need the velocity of the electric motor to be diverse during operation.
This is usually achieved using a VFD or Variable Frequency Drive, which controls the speed by modifying the frequency fed to the motor. Selecting the most appropriate motor and VFD type depends upon a number of factors, however, it is necessary to first look at the way the characteristics of a engine change when the velocity is reduced.
A motor usually includes a base speed, specific by the manufacturer, that it is definitely designed to operate at. Nevertheless, if a engine is managed below the base speed, it may experience reduced efficiency of the cooling system. Especially with commonly used Totally Enclosed Fan Cooled (TEFC) and ODP (Open Drip Evidence) motors, where the cooling system consists primarily of a shaft-mounted lover, a decrease in speed outcomes in reduced airflow over the electric motor and lack of cooling, and high temperature buildup occurs. Especially when the motor is operated with full torque at low speeds, heat can easily build up in the motor to damaging levels.