The U.S. Department of Energy (DOE) has been regulating energy efficiency for electric motors since 1997, when the Energy Policy Act went into effect, requiring most 1 to 200 hp general-purpose motors to meet NEMA Energy Efficiency standards. Since then, the DOE energy efficiency regulations have evolved, with the Energy Independence and Security Act (EISA) […]
What’s the difference between an EC motor and a BLDC motor?
Deciphering motor terminology can be frustrating, especially when comparing the operation and performance of various motor types. For example, some motors are characterized by their speed (synchronous or asynchronous) while others are characterized by their commutation method (brushed or brushless). And then there’s the issue of whether the motor is operated with AC or DC […]
What is a Halbach array and how is it used in electric motors?
A Halbach array is arrangement of permanent magnets that creates a stronger field on one side while reducing the field on the other side to near zero. This is accomplished by orienting the magnets so that their poles are out of phase, typically by 90 degrees. This orientation essentially re-routes the magnetic field below the […]
What’s the difference between cogging torque and torque ripple?
The basic operation of an electric motor relies on the interaction between the rotor’s permanent magnets and the stator’s energized windings. But even when the motor is not powered and no current is flowing though the windings, there is a magnetic attraction between the permanent magnets of the rotor and the ferromagnetic teeth of the […]
Severe duty motors: What makes them suitable for harsh applications?
While there is no broad standard that defines severe duty motors, the IEEE 841-2009 standard, which addresses “premium efficiency, severe duty, totally enclosed fan-cooled (TEFC), squirrel-cage induction motors — up to and including 370 KW (500 hp),” is often used as a benchmark. However, this standard was written for the petroleum and chemical industries, and many […]
External rotor motor basics: Design and applications
Conventional brushless DC motors are constructed with a permanent magnet rotor located inside a wound stator. But one type of DC motor is designed with the rotor on the outside and the stator and housed inside the rotor. Permanent magnets are mounted on the inner diameter of the rotor housing (sometimes referred to as the […]
How do pulse-duty servo drives and motors differ from continuous-duty versions?
Servo systems are applied in a wide range of applications, from intermittent operations that require high torque output for quick acceleration and deceleration — such as pick-and-place from a conveyor — to processes that call for nearly uninterrupted operation with constant speed and torque requirements — such as printing, roll feeding, and labeling. Given these dissimilar application requirements and […]
Build conveyors in real time with Dorner’s new 3D Preview
Functionality at its best! Customers can now receive real-time updates as they design and modify conveyor systems using 3D Preview in DTools, Dorner’s online conveyor configurator. 3D Preview, a fully interactive, live experience for customers that gives them more information than ever before, is now available for Dorner’s 2200 Series Precision Move Pallet System. When building their […]
How can a universal motor operate on either DC or AC supply?
A universal motor is a series-wound motor — meaning that the field and armature windings are connected in series — and is mechanically commutated with brushes and a commutator. Although its construction is very similar to a series-wound DC motor, a universal motor incorporates several modifications that allow it operate properly on either DC or AC […]
How an IDE reduces development time in PACs
Applications that require complex process or motion control also require elaborate and complicated programming — often across multiple components, functions, and parameters. But thanks to the integrated develop environment found in programmable automation controllers (PACs), the programming task for these complex applications is faster, less burdensome, and more reliable. When ARC Advisory Group introduced the term “programmable […]