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Millions of parts are available for same-day shipping and next-day delivery.
Save money on downtime with the most trusted leading experts in automation replacement and repair.
Millions of parts are available for same-day shipping and next-day delivery.
45+ years of experience to help you find an ideal replacement or repair solution.
We stand behind our quality by offering a complimentary 2-Year DO Supply Warranty on all products.
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.
Shop with confidence knowing that we offer fast shipping and best-in-class customer service. Explore our large inventory of in-stock automation parts backed by the guarantee of a 2-year DO Supply Warranty.
Save money on getting your automation parts repaired for less, backed by our 2-year DO Supply Warranty. We offer quality repairs at the best prices, carried out by expert technicians.
We want to buy your industrial automation surplus equipment, including PLCs, drives, motors, HMIs, and more.
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Surplus Allen Bradley, GE, Fanuc, Emerson, Eaton, Mitsubishi, Omron, and more.
Discover insightful industry knowledge
Variable Frequency Drives (VFDs) are widely used in modern industries to optimize process control, minimize power consumption, and extend equipment lifespan. The Allen-Bradley PowerFlex series stands out for providing high-performance motor control with precise torque control and simplified automation integration. However, VFD operations can induce damaging high-frequency stray currents and common-mode voltages on motor shafts. These high-frequency currents often discharge through the motor bearings, resulting in accelerated bearing wear and premature equipment failure. The destructive impact of VFD-induced high-frequency currents on motor bearings is a widely recognized engineering issue. Connecting standard AC motors to variable frequency drives (VFDs) like the PowerFlex drives exposes them to stray currents and high-frequency voltage spikes. When under pure sinusoidal utility power, destructive stray currents do not exist. Catastrophic mechanical failure and structural degradation...
For many facilities, uptime is a priority when selecting which equipment to deploy in their line. Because of this, redundancy modules and spares are kept so that high-priority equipment and processes can be repaired with minimal downtime. As you can imagine, this is an effective technique when properly executed. Sometimes these processes are designed so well that they simply chug along for years and years without having to dust off the replacement in the supply cabinet. Drives that have been obtained for replacement now sit on the shelf waiting for the baton to be passed, and it can be years before it does, and plugging them in might just bring more issues. When it comes to storing drives, there is no official expiration date printed on the part, but guidelines for the amount of time a drive can sit without power. This time frame varies across manufacturers: Rockwell’s PowerFlex guidelines specify 2 years, while ABB and Eaton specify 1 year. This is because the electrolytic capacitors...
In the modern age, motor control isn’t as simple as it looks. There’s matching nameplate specifications, determining if the load you’re driving needs certain features like regeneration, or even figuring out if it’s worth futureproofing. With VFDs being so common today, it is easy to assume they are always the better answer. But that’s not always the case. Sometimes, less really is more. If the application only calls for smooth starting and stopping, a soft starter could be the cheapest, simplest, and most cost-effective choice. A soft starter, as the name implies, is a motor controller that gradually and smoothly increases a motor’s speed until its desired RPM, rather than slamming voltage into it all at once. This is a desired feature as its ability to reduce inrush current and limit peak electrical demand on motor start-up reduces mechanical stress on the system and prevents overcurrent scenarios. Source SMC Plus Soft Starters Here To achieve this, soft starters use thyristors, or...