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 […]
FAQs + basics
What’s the difference between micro, low, medium and high-power VFDs?
The simplest answer may be that there seems to be no one simple and straightforward answer to the question. It helps to clarify what exactly these designations mean. For starters, there are several different ways that VFDs can be classified. One way VFDs are classified is by the electronic topology of their inverter stages. So […]
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 […]
What are some networking options for PC-based controls?
The short answer is that there are many networking options for PC-based controls, not all that dissimilar to non-PC-based controls. A good number of them are based on the Ethernet protocol as that is the most common networking protocol for PCs. PC-based controls have become more common in industrial settings as they have steadily displaced […]
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 […]
Brushless dc motors for industrial power tools: Comparison of options including slotless motor variations
Industrial power tools have operating profiles that differ from those of most other motor-driven applications. That’s why motors that go into these tools need specialized designs. By Thomas Baile, Business Development Manager | Portescap Most electric-motor-driven designs demand torque for the entirety of their motion. In contrast, power tools for fastening, gripping, and cutting applications […]
What’s the importance of proper depth of engagement between a belt and its drive pulley?
Belt and pulley drives are used in a wide range of industrial applications. In putting together a system properly, factors to consider include correctly sizing the pulleys and the belt. Part of that correct sizing involves the depth of engagement between the belt and the pulley. Common belt types include V belts and synchronous belts. […]
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 […]
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 […]
What are motion-control cards and boards?
Motion controller cards and boards can take the place of PCs in some types of control systems … and there are a few different configurations possible. In one configuration, the motion card can be housed in box with I/O and networking connections and mounted directly to the machine or process it controls. Control programs can […]