We found 286 posts about Drives & Motors from DO Supply, a global automation parts
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Drives that control motor speed such as Variable Frequency Drives (VFDs), AC Drives, and Variable Speed Drives (VSDs) include a rectifier unit, in which the AC voltage is supplied to the drive is converted into DC voltage. In most of these motor drives, this rectifier unit makes use of standard P-N junction diodes (two-layer diodes) to build different types of rectifier circuits like half-wave, bridge, and full-wave rectifiers. However, if high voltage is applied to any of these two-layer diode rectifiers, its diodes are likely to get damaged. For this reason, motor drives using rectifier units made of P-N junction diodes cannot operate reliably at high supply voltages. To overcome this limitation, a special type of rectifier that could withstand high voltages was developed. This rectifier is the Silicon Controlled Rectifier (SCR). SCRs are often used in applications where a large amount of power needs to be switched, though it’s necessary to keep their control voltage and current low...
In industrial automation, the term “drive” is often associated with motor drives, which are types of motor controllers described using various terms such as Variable Speed Drives (VSDs), Adjustable Speed Drives (ASDs), Inverter Drives, Adjustable Frequency Drives (AFD), Variable Frequency Drives (VFDs), AC Drives, Variable-Voltage Drives, …etc. However, even though these terms are used interchangeably, they have different meanings depending on the technique used to control the motor speed and the drive’s application. For example, a Variable Speed Drive is a more generic term that applies to electronic or mechanical devices which control either motor speed or the speed of motor-driven equipment like compressors, fans, pumps, etc. Whereas, a VFD is a device that uses power electronics to vary the frequency of the input voltage to a motor, thereby controlling the motor speed. On the other hand, an Adjustable Speed Drive is also a more generic term that applies to both electrical and...
Allen Bradley MPL Servo Motors A servo motor is a linear or rotary actuator that allows for precise control of linear or angular position, acceleration, and velocity. A typical servo motor system consists of a suitable electric motor coupled to a sensor for position feedback. The motors’ control circuit, which includes the position sensor, provides feedback on the real-time position of the motor shaft. With this feedback, the servo motor can rotate with great precision. But for a servo motor system to be complete, it also requires a servo drive that uses the position feedback sensor to precisely turn the servo motor at some specific angles or distances. Simply put, a servo motor is just a simple electric motor that runs through a servo mechanism. Servo motors are broadly categorized as AC-powered or DC-powered. But there are many other classifications depending on the operating characteristics and gear arrangement of the servo motor in question. The different types of gear...
A Variable Frequency Drive (VFD), also known as a Variable-Speed Drive (VSD), Adjustable-Frequency Drive (AFD), Frequency Converter (FC), Adjustable Speed Drive (ASD), Microdrive, AC drive, or an Inverter driver, is an electronic controller used to regulate the rotational speed of induction or synchronous electric motors. The VFD controls motor speed by varying the frequency of the supply voltage being used to power that motor. To practically execute this, a typical VFD system consists of four main components; namely, the Rectifier Circuit unit, DC Bus and Filter unit, Inverter Circuit unit, and the control unit. These four units function together to adjust the AC frequency of the voltage supplied to a connected motor, thereby controlling the motor’s RPM (motor speed in revolutions per minute). First, the VFD takes in fixed frequency AC voltage into the rectifier section, which consists of diodes (4 or 6) or thyristors that convert the input AC voltage into unfiltered DC voltage. This...
VFDs or Variable Frequency Drives are controller systems including motors that give varying output speed as per input command. The capacitor forms DC links the whole VFD system. The voltage across this DC link is an important parameter to be controlled. This voltage is input to the inverter and thus acts as a reference voltage in the system. Variations in DC link voltage or voltage across the capacitor impacts the speed and performance of motor greatly. The selection of capacitor is equally important as its size will define the ripple factor, noise, and smoothness in the running of the motor. While it is important to know the significance and working of capacitors in a drive system, let’s understand the basics of the drive system, associated terminologies, and common topologies. To understand the purpose of capacitors in VFDs, one should have an idea of the purpose of VFDs and their basic work topology. Variable Frequency Drives are electromechanical systems in which the speed and...
The term VFD stands for Variable Frequency Drive. It is a type of motor controller which drives an electric motor by varying the frequency and voltage supplied to that motor. Variable Frequency Drives (VFDs) are also known as AC Drives, Inverters, Variable/Adjustable Speed Drives, Inverters, Variable-Voltage Drives, Microdrives, Frequency Converters, or Variable Frequency Inverters (VFIs). Frequency, given in Hertz (Hz), is directly related to motor speed in revolutions per minute (RPM). Thus, by adjusting the input frequency the motor speed can be varied accordingly. For example, the higher the supply frequency, the more RPMs the motor will exhibit. VFDs are best suited for applications in which an electric motor is not required to run at full speed, as they can ramp down the supply voltage and frequency to meet the requirements of the motor’s load. In case there is a change in the application’s motor speed requirements, the VFD can be set to ramp up or turn down the motor speed as...
An MP-Series Low-Inertia Servo Motor (Cat. No. MPL-B320P-MJ22AA) MPL servo motors are a family of MP-Series™ low-inertia rotary servo motors, from Rockwell Automation under Allen-Bradley Bulletin MPL. They are compact and highly dynamic brushless servo motors consisting of premium permanent magnets. They feature multi-turn or single-turn high resolution encoders, and they are available with 24 Volts DC brakes. The MPL units use innovative design characteristics and advanced winding technology to reduce motor size while delivering considerably higher torque. They thus leverage their high torque-to-size ratio to provide high-performance motion systems, which require servo motors with quicker acceleration and excellent torque performance. The MP-Series™ low-inertia servo motors are typically used with PowerFlex drives and Kinetix drives from Allen-Bradley. The Allen-Bradley® MPL servo motors feature two input voltage classes: 400V-class and 200V-class. They are available in nine (9)...
Allen Bradley PowerFlex4 The Allen-Bradley PowerFlex 4 is a series of compact Variable Frequency Drives (VFDs), which provide powerful and precise motor speed control. These drives are programmed for Volts-per-Hertz (V/Hz) operation mode, as the default motor control setting. They are designed for ease of use and optimal flexibility, with a space-saving design. In addition, PowerFlex 4 drives provide users with intuitive interface devices including an integrated keypad with control keys and a local potentiometer. Moreover, the PowerFlex 4 drives are an economical speed control alternative for a variety of industrial applications including fans, conveyors, machine tools, pumps, and material handling systems. Essentially, PowerFlex 4 drives are designed to meet the demands of global Original Equipment Manufacturers (OEMs) and end-users for simplicity, cost efficiency, and space savings. They are the smallest and most cost-effective members of the compact, Allen-Bradley PowerFlex®...
The Allen-Bradley PowerFlex® is a family of Compact-class AC drives developed by Rockwell Automation, to deliver cost-effective solutions for simple system integration or standalone machine-level control applications. In general, PowerFlex drives provide extreme application flexibility, linear scalability, and excellent performance while simplifying the management of workload infrastructure. PowerFlex 40 and 40P drives are the most compacts and cost-effective members of the Allen-Bradley PowerFlex® series of AC drives. They are a general-purpose class of AC drives, which provide a compact package to optimize application versatility and panel space. They are designed for ease of use, providing users with powerful and dynamic motor speed control in a compact, space-saving design. This article seeks to provide an in-depth comparison of the features and control capabilities of PowerFlex 40 and PowerFlex 40P AC drives. Allen Bradley PowerFlex 40 Allen-Bradley PowerFlex® 40 drives are an...
Allen Bradley’s PowerFlex 750 series of alternating current drives are available in a variety of enclosure ratings to meet a wide range of requirements as per the user’s application. It’s critical to pick the correct enclosure ratings for your drive since you don’t want your system to go down or production to be affected if your drive fails. Enclosures for drives are evaluated according to their compatibility for specific applications and how well they shield equipment. A number is assigned to each type of enclosure depending on its capacity to bear up environmental factors. For this drive’s series, enclosures have Ingress Protection (IP), NEMA, and UL Type classifications. We will look into the details of these standards, so you’ll know precisely what to look for while selecting a drive from the PowerFlex 750 series. We’ll only concentrate on available enclosures for these drives in this guide. Then, we will discuss possible enclosure codes – a combination of NEMA, IP, and UL...
Induction motors are extensively used for a variety of industrial and domestic applications. For industrial applications, three-phase AC motors are the most popular due to their simple and robust construction, high-power output, low maintenance requirements, high efficiency, and suitability to function reliably in any working condition. However, at standstill, the windings of such motors are characterized by a low impedance. They thus draw huge amounts of current during start-up to accelerate to nominal speed. This makes them prone to input current surge known as “inrush current”. A high inrush current is usually 5 to 8 times higher than the rated current of an induction motor at full load. And since induction motors are not designed to tolerate the high inrush, their windings can get quickly damaged which reduces the motor’s performance and lifespan. Also, high inrush currents are likely to cause a huge dip in the line voltage resulting in low levels of the supply voltage. This can...
VFD stands for Variable Frequency Drive. It is a type of motor controller that drives an electric AC motor by varying the voltage and frequency of its power supply. By adjusting the frequency of the AC voltage being supplied to the motor, the VFD is able to control the speed of the motor. This is possible because, Frequency, given in Hertz (Hz), is directly related to the motor speed given in Revolutions per minute (RPM). In other words, the faster the frequency of the supply voltage, the faster the motor speed in RPM. There are a variety of other names that may be used to refer to a Variable Frequency Drive (VFD), including: Adjustable Speed Drive Adjustable Frequency Drive Variable Frequency Drive Variable-Voltage Drive Variable Speed Drive(VSD) Frequency Converter Variable Frequency Inverter(VFI) AC Drive Microdrive Whatever the name used, a Variable Frequency Drive is always a type of motor controller used to drive and control electric AC motors. There are a variety of factory and...
Maximum Current (Imax) Amps (A) Amps Voltage Volts (V) Volts Stepper Motor Inductance (L) milliHenry (mH) mH Steps Per Revolution Steps Steps Results Maximum Power Watts Minimum Time per Step ms Maximum Speed revolutions/second A stepper motor is simply an electromechanical device that converts electrical power into mechanical power. It is a popular type of brushless, synchronous electric motor that converts input discrete(digital) pulses into mechanical shaft rotations. It divides a full shaft rotation into an expansive number of precise movements called steps. If you drive a stepper motor using a DC power supply that is sequentially switched, then the rotor shaft of the stepper will consist of discrete angular movements with uniform magnitudes. Unlike other standard types of DC (Direct Current) motors which rotate continuously for an arbitrary number of spins until the DC voltage being supplied is turned off. Stepper motors are a type of discrete input-output device for precise...
Both Eaton S801+ and Eaton S811+ industrial soft starters, products of Eaton’s electrical business are very compact and smart electronic devices to smoothly start three-phase induction motors. Both share many common features and are distinct slightly from each other. This article focuses on some of their major characteristics which could be related to their power or control actions, hardware features, and/or environmental specifications with reference to applications, and outlines all similarities as well as differences. Both soft starters S801+ and S811 are very compact so they could be retrofitted in existing wye-delta starters, NEMA (National Electrical Manufacturers Association) and IEC (International Electrotechnical Commission) starters, or other soft starters. As this feature of S801+ and S811+ starters makes replacement of the whole system or structure avoidable, so huge expenses are emitted. This feature makes these soft starters more usable and demanding. Eaton Corporation...
A Soft Starter is a device that provides an alternative startup method to a typical AC motor with fewer power requirements at start-up. It reduces the amount of drawn inrush current and limits the motor starting torque; this helps reduce potentially damaging mechanical and electrical shocks on the motor system. When a soft starter is added to a motor’s circuit, it continuously regulates the motor’s supply voltage during the start-up phase. This means that the motor will gradually adjust to the machine’s load behavior. So, the soft starter provides the motor with a smooth acceleration up to full speed. This improves the operating behavior and lengthens the service life of your motor; it also smooths workflows. As the name suggests, soft starters are mainly used in the start-up phase of electric motors or other mechanical operating equipment. But they can also be used to stop, accelerate, reverse and protect such equipment. Moreover, they are used to reduce motor heating in case of...