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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.
Shop a large selection of manufacturers and product lines.
Surplus Allen Bradley, GE, Fanuc, Emerson, Eaton, Mitsubishi, Omron, and more.
Discover insightful industry knowledge
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...
When a plant experiences a planned shutdown, turnaround, holiday outage, or utility maintenance window, one or more PowerFlex drives fail within minutes or hours of re-energization. This is a distinct, recurrent pattern that maintenance engineers in the heavy industry can quickly identify. After years of trouble-free operation, the drive suddenly malfunctions, trips a breaker, or, in the worst situations, literally destroys an IGBT module. It is a foreseeable result of power electronics deteriorating when idle, contaminants and moisture building up when a drive isn’t producing heat, and a plant’s restart cycle interacting with both. The difference between considering every shutdown-related failure as a mystery and creating a restart strategy that stops it is an understanding of these mechanics. The internal parts of a PowerFlex drive are designed to operate continuously or almost continuously. Long-term proper operation of the DC bus electrolytic capacitors, IGBT gate driver boards...