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Millions of parts are available for same-day shipping and next-day delivery.
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DO Supply is a global leader in replacement parts for industrial automation equipment. Our mission is to elevate the standard of expert support, speed, and reliability for your need-it-now automation replacement and repair needs. Whether it's PLCs, drives, motors, HMIs, or more, you can count on us for the best service and fastest solutions.
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Discover insightful industry knowledge
Modern motor control relies heavily on variable frequency drives, yet the components that safeguard them are often the first to suffer budget cuts. Line reactors, also known as input reactors, are often seen as optional add-ons rather than necessary safety measures. The electrical mechanics underlying reactor protection, the failure types that reactors avoid, and the cost justification for implementing them on each drive installation are all discussed in this article. In simple terms, an input reactor is a three-phase inductor placed between a drive’s input terminals and the incoming AC power source. Its purpose is surprisingly straightforward: it increases the line’s impedance. In a drive environment, this impedance smooths out the abrupt current spikes that occur each time the drive’s rectifier bridge charges its DC bus capacitors, as it resists rapid current changes. Drives convert incoming AC to DC using an SCR bridge rectifier or diode. Because the current is drawn in brief...
Teams with short timeframes set up Rockwell’s PowerFlex drives every day, and most of that work only touches the handful of parameters needed to make a motor spin: voltage, frequency, and a start reference. Once the motor turns, the commissioning checklist gets signed off, and everyone moves on to the next job. But PowerFlex drives feature dozens of secondary parameters that regulate efficiency, thermal load, fault tolerance, and lifespan. When these are left at their defaults and never reviewed, the drive still runs, but often well below its capabilities. Factory settings on a PowerFlex drive exist for one reason: broad compatibility. They are built to work across a wide range of motors and applications, which means they are rarely ideal for any single fixed installation. A default acceleration ramp, carrier frequency, or stall timer is enough to get a drive running. Still, it won’t match the thermal properties of a specific motor, the inertia of a specific load, or the electrical...
It’s no secret that AC drives, particularly variable frequency drives, have been efficiency and productivity boosters for automation facilities. Manufacturers boast about how their drives can pay for themselves with the money you save with reduced energy costs, while also reducing mechanical wear throughout the system For those who want to stick to their guns and continue using their conventional motor controller until it breaks, there is a cost to waiting. AC drives are effective because they address many of the inherent inefficiencies and mechanical stresses associated with controlling motor speed using fixed-speed equipment. Without one, a facility may be paying a hidden tax through wasted energy, increased maintenance, reduced process control, and premature equipment wear. One of the biggest arguments against installing an AC drive is often the initial cost of the system. One may argue that an AC drive may be more difficult to install, and if done improperly, could lead to even...