A relay is an electrically controlled switching device. It consists of an electromagnet and a set of contacts that open or close when voltage is applied to the electromagnet. It was invented by the U. In the beginning, electromechanical relays were used to transfer the Morse-code signal to long-distance through a wire. Today, they have a wide variety of applications and have become an important part of industrial control and automation systems. A Relay is an electro-mechanical or solid-state device, used to control a device or a circuit electrically by applying a control signal to its coil.
How to Test a Relay at Home - Voltage & Function Test - Mechanic Base
Differential protective relaying is the most positive in selectivity and in action. It operates on the principle of comparison between the phase angle and magnitudes of two or more-similar electrical quantities. Comparing two electrical quantities in a circuit by means of differential relays is simple in application and positive in action. For example, in comparison of the current entering a line and the current leaving it, if more current enters the protected line than leaves it, the extra current must flow in the fault. The difference between the two electrical quantities can operate a relay to isolate the circuit.
protection relay training courses
Learn the fundamentals behind hassle-free relay testing, on your schedule. Relay testing can be frustrating! But what if you could avoid all of that, learn to navigate almost any testing scenario, and become a true relay testing expert? My name is Chris Werstiuk. I'm an engineer, power system electrician, electrical technologist, and instructor who's spent the last 20 years learning the craft of relay testing through trial and error in nuclear power plants, commercial buildings, and almost everything in between.
CT saturation calculator spreadsheet is available from Relaying Committee website under knowledge base. Please download from "I-subcommittee report CT saturation Calculator", a zipped file. This will be used during lectures to show the effects of CT saturation. Lecture Slides.