Availability
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
In a VFD-dominated industrial world, soft starters still have their place in motor control. They are a reliable way to protect your motors, the loads they move, and the systems they’re attached to. On top of that, they fit nicely into a budget-conscious build when a facility doesn’t need the extra features or programming that VFDs offer. Not every soft starter is built for the same job. Some are basic starters designed for simple start-and-stop control. Others are more advanced units with stronger protection features, better diagnostics, communication options, and more control over how the motor starts and stops. Each type has its own advantages, limitations, and best-fit applications. A variable frequency drive, or VFD, is the more common component to pair with a motor for industrial control. VFDs can control motor speed, improve efficiency in variable-speed applications, support advanced diagnostics, and, in higher-end models, offer features such as regenerative operation and...
General-purpose automation just cannot meet the demands placed on a control system by high-speed production. A vision-guided robotic cell that makes accept/reject decisions in less than two milliseconds, a packaging line that produces 1,200 units per minute, or a multi-axis servo system that coordinates ten simultaneous motion profiles are all unable to withstand the scan time variability, communication latency, or processing constraints that are acceptable on a typical discrete manufacturing line. A system that operates at line speed or one that becomes a bottleneck depends on the choice of processor generation, motion architecture, task structure, and communication topology within Rockwell Automation’s ControlLogix platform, which is specifically designed for this environment. This article discusses each of those selection decisions in the context of high-speed manufacturing requirements. Controllers that offer complex automation, integrated safety, motion control, and scalable...
There was a time when PLC memory planning mainly consisted of counting I/O points, estimating the number of instructions, and making sure that the program would fit inside the controller’s memory. This approach worked when a PLC’s primary responsibility was reading switches, controlling outputs, and keeping a machine moving through a relatively simple sequence. Fast forward to modern facilities, and you will see that PLCs are asked to do a lot more. In addition to running the core program, modern PLCs may coordinate motion, communicate with dozens of devices, and retain maintenance data. Every function that a controller is told to do requires memory, even when it doesn’t add many visible rungs to the program. Because of this, sizing a PLC for its memory can be an easy oversight. While it may seem to have enough processing power and I/O capacity for an application, it can fall short on program memory, data memory, retentive storage, or even communication resources. PLC memory is...