Industrial motors come in a wide range of horsepower, base speeds, voltage ratings, variable speed range and motor efficiency.
Industrial motors vary in enclosure types, insulation systems, frame construction, encoder capabilities, or lack thereof, and the environments in which they can be used. Industrial motors touch many industries, including gas and oil, mining, agriculture and agribusiness, water and wastewater, pulp and paper, aerospace, food and beverage, military and defense, material handling and transportation and utilities.
Industrial motors are widely categorized into two categories: DC motors and AC motors. DC motors, which operate with a direct current, are less commonly used for industrial purposes, as they are an older, less independent technology. However, when coupled with a DC drive, they provide very precise control. They have two major advantages as industrial motors.
First, it is easy to control their speed in a wide range; historically their torque characteristics have been easier to customize than AC motors. Second, their reduced overall dimensions allow for a significant saving of physical space on the plant floor. DC motors, however, do have several disadvantages.
One of the disadvantages of brush DC motors is the fact that they need brushes to connect to the rotor winding. In addition to the added cost, brushes wear quickly, especially in low-pressure environments. DC motors thus cannot be used on aircrafts. Also, if its working environment contains explosive materials, sparks from the brushes could prompt an explosion.
However, many manufacturers make brushless DC motors to remedy some of these issues. They work well as industrial motors for conveyors, elevators, extruders, material handling, paper, plastics, rubber, steel and textile applications, automobile, aircraft, portable electronics and all speed control applications.
AC, or alternating current, motors are far more widely used as industrial motors. General advantages of the AC motor include: simple design, low cost, reliable operation, variety of mounting styles, the fact that replacement parts are easily found and the fact that they have many different environmental enclosures.
In fact, its simple design is the main reason that they are overwhelmingly preferred for industrial applications. Their disadvantages include: expensive speed control, poor positioning control and an inability to operate at low speeds. AC motors are found in air conditioners, washers, dryers, industrial machinery, fans, blowers, vacuum cleaners and more.
In their breadth, the applications of industrial motors are extremely diverse, from industrial pumps to disc drives, and their power sources are extremely diverse as well. Their DC power sources include batteries, motor vehicles and rectifiers, while their AC power sources may be power grids, inverters or generators.