Archive For: Motor Controls

AC Drive Applications

AC Drive Applications

When powering AC motors, the electrical supply can be at full power to run at full speed, or at variable power to run at variable speed. Applications with fluctuating loads benefit from the variable speed provided by an AC drive because less power is used at lower loads and speeds, and this article explains how ... Read More
 
Overview of AC Motor Control Options

Overview of AC Motor Control Options

Most automatic controls involve motor control in some way, especially in factory automation. Applications such as pumps, fans, robotics, and conveyors use motors. Whether general-purpose 3-phase ac motors, which are great for simple on/off systems, or the inverter-duty motors specifically designed for operation with variable frequency drives (VFDs), one could say that motors are ubiquitous in nearly ... Read More
 
How to Choose a General Purpose Motor vs. Inverter-Duty Motor

How to Choose a General Purpose Motor vs. Inverter-Duty Motor

General purpose motors have been around for many years. They are the workhorse of almost every industry. An inverter-duty motor is a much newer concept that became necessary as motors began to be driven by VFDs (inverters or AC drives). An inverter duty motor can withstand the higher voltage spikes produced by all VFDs (amplified ... Read More
 
How to Select a Soft Starter for Your Motor

How to Select a Soft Starter for Your Motor

What may seem to be a simple task of selecting a soft starter for your motor may be a more demanding task than first meets the eye. “I just need to know the HP and Voltage to pick the correct one, isn’t that right?”
 
AC Motor On/Off Controls | Automation Notes

AC Motor On/Off Controls | Automation Notes

Most control systems have to make things move, and that usually involves motors. Lifting, pumping, robotics, conveyors, fans – pretty much everything uses a motor of some kind. General purpose one- or three-phase AC motors are great for simple on/off systems; Inverter-duty motors are specifically designed for operation with variable frequency drives or VFDs. General ... Read More
 
Specifying and Sizing Motor Starters

Specifying and Sizing Motor Starters

There are four basic motor control options available: Basic contactors, traditional starters, manual motor starters, or combination starters. A basic contactor is a special purpose relay that is used to control large electrical currents. Similarly, a traditional starter utilizes overload relays, auxiliary and alarm contacts, and mechanical interlocks to create a reversing unit. On the other ... Read More
 
Upgrading Pump Stations with PLCs

Upgrading Pump Stations with PLCs

When relays and timer circuits get old, they cause problems. Replacing them with PLCs keeps pumps running smoothly. One of the most important jobs of a water distribution system is to reliably deliver water to its customers. At our water district in California, we had pumping stations (Figure 1) with relay-based controls that were more ... Read More
 
Semiconductor Breakthroughs Promise Smaller, Faster Chips

Semiconductor Breakthroughs Promise Smaller, Faster Chips

Computer chips are always getting smaller and faster – right? Historically, this has been the trend. This trend was first observed by Intel co-founder Gordon Moore in 1965, and the term “Moore’s Law” was coined several years later. For over forty years this “law” has held, chips have gotten more complex, and transistors have shrunk ... Read More
 
How to Wire a Motor Starter

How to Wire a Motor Starter

The Technical Support page on the AutomationDirect website is full of valuable information and is available 24/7. The following is referenced from the Technical and Application Notes section. A motor starter is a combination of devices used to start, run, and stop an AC induction motor based on commands from an operator or a controller. ... Read More