While there are some things to consider when specifying gearmotors such as output shaft power or torque, there are also some things to avoid when choosing one. In particular, don’t negate the motor efficiency gains with inefficient gearing so that you can maximise the overall efficiency of your geared system. For instance, if you need a gearmotor for tight spaces, a right-angle worm-gear reducer can be efficient by up to 50%.
However, a spur gear and helical gear that is specified for parallel-shaft reducer would be more efficient to use by as high as 98%. For much tighter spaces, higher-efficiency spur and helical gearmotors which are stacked in a vertical configuration in an offset parallel-shaft reducer offer a better solution. This is because of their output shaft forms either S- or U-shaped configuration that is relative to the driving motor.
In addition to avoiding negating the motor efficiency by choosing incorrect gear type, it’s also a big mistake to undersize or oversize the gearmotor. Improper sizing has to be prevented at all cost as it can lead to a lot of motor failures and higher inefficiency. This is where the service factor becomes so critical. Without taking it into account, the selection of gearmotors will lead to premature wear and tear of the motor or unwanted damages can occur. Despite the fact that the torque and speed required to handle two different motor applications are just the same, their service factors do vary and so is the choice for gearmotors.
On the other hand, oversizing affects the efficiency of the motor. While it’s true that a 10 hp gearmotor can work at much higher rated load, it doesn’t mean it’s always better to choose it over a 5 hp model. It still depends on your specific application and choosing a greater hp than what is necessary means wasted power and energy, and so efficiency in running an unloaded motor. So, always remember to select only the right type and size of gearmotor that best suits your application.