Motors Control

Programmable logic controllers (PLCs) are useful in increasing production and improving overall plant efficiency. PLCs can control individual machines and link the machines together into a system. The flexibility provided by a programmable logic controller has allowed its use in many applications for manufacturing and process control. Process control has …

The type of programmable logic controller (PLC) that is used depends upon the application, size and number of loads to be controlled, need for monitoring and reprogramming the circuit, and amount of control required (ON/OFF to anywhere in between). Budget cost and the knowledge level of personnel who will need …

AC motors produce work to drive a load by a rotating shaft. The amount of work produced is a function of the amount of torque produced by the motor shaft and the speed of the shaft. The primary function of all motor drives is to control the speed and torque …

An AC motor drive decelerates a motor at a controlled rate by placing an electric load on the motor. The advantage in using a motor drive to apply a braking force is that maintenance is kept to a minimum because there are no parts that come in contact during braking. …

Electronic Overloads New motor starters normally include an electronic overload instead of heaters. An electronic overload is a device that has built-in circuitry to sense changes in current and temperature. An electronic overload monitors the current in the load (motor, heating elements, etc.) directly by measuring the current in the …

AC motor drives are referred to as variable frequency drives, adjustable frequency drives, inverter drives, vector drives, direct torque control drives, and closed-loop drives. Regardless of how an AC drive is referred to, its primary function is to convert the incoming supply power to an altered voltage level and frequency …

Control devices such as push buttons, limit switches, and pressure switches are connected into a circuit so that the circuit can function in a predetermined manner. All control circuits are basic logic functions or combinations of logic functions. Logic functions are common to all areas of industry. This includes electricity, …

Although there are many different types and sizes of motors, most electric motors used in commercial and industrial applications can be classified as single-phase (1 φ) or three-phase (3 φ). Single-phase motors are commonly used in some commercial applications such as garage door openers, sump pumps, automatic doors, and ceiling …

The nameplate on an individual electric motor tells the story of what the motor is capable of and its electrical supply requirements. The National Electrical Manufacturers Association (NEMA) specifies the following data is to be listed on the individual motor nameplates: Duty Cycle or Time Rating Efficiency Frame size Frequency …

Three phase induction Motor rotation can be reversed by changing any two of the three lines feeding power to the motor. It is common standard practice to switch line 1 and line 3. When the motor needs to be run in a clockwise and a counterclockwise rotation, a reverse starter …

Jog Circuit Definition The jog circuit is important to create a circuit that will allow the operator to momentarily energize the circuit without the need of pressing the stop pushbutton. Jog circuits allow the operator to move loads to a set position preventing the load from over traveling to the …

Basic control circuits are a combination of electrical logic formations of wires.  These combinations are designed to enable a machine to complete specific tasks. Some of the most complex circuits in industry stem from some of the most basic control circuits electricians must learn and be able to sketch and …

Single phase induction motors are traditionally used in residential applications such as ceiling fans, air conditioners, washing machines, and refrigerators. These motors consist of the split phase, shaded pole, and capacitor motors. An AC (alternating current) motor is an electromechanical device that converts electrical energy into mechanical movement through the …

As there are many PLC manufacturers, there are as many software programming packages. Each manufacturer developed their own software with no set standards other than it must follow relay ladder logic so that technicians could easily be trained without having to be software engineers. Two terms describe PLC software; open …

Programmable Logic Controllers Introduction Programmable Logic Controllers (PLC’s) were first used commercially in the 1960’s. Since then, the PLC industry has grown such that no medium to a large-scale manufacturing facility in the United States can function efficiently without them. It has created a multi-billion dollar a year industry. This …

Variable Frequency Drive Introduction This resource is about AC Drives also known as VFDs or Variable Frequency Drives. Modern semiconductors have revolutionized handling the higher power required to run electric motors. Variable Frequency Drive is a technology where the rotational speed of an electric motor is controlled or varied electronically. Electric …

Pilot Devices Types Pilot devices can be some type of audio-visual indicator or a type of switching device used to control the flow of energy to a process. Think about the light switch in a room. This device is used to control the flow of energy to the light and …

Low Voltage Components Low voltage components make up the other half of the motor controls panel. Voltage is reduced and distributed to different components to achieve the desired function. This is a twofold purpose: safety and power consumption. By reducing the voltage, technicians that troubleshoot a live panel are less …

Motor Panel Overview Motor Control Panels (MCP) are used in just about every type of industry; from offshore drilling platforms to a production line that makes pastries and cookies in a bakery factory. It empowers the manufacturer to be able to duplicate and automate their process with little or no …