Optical fiber cables transfer data signals in the form of light, which travel significantly faster and farther than those used in traditional conductors. Fiber optic cables are a top choice for high-speed communication systems and can also be used as sensors to measure and monitor various quantities.
Over-current Relays: Inverse Time Characteristics Explained
Overcurrent relaying is one of the most simple and economical types of protection used for power system feeders, transformers, generators and motors. Since the advent of simple electromechanical elements, to advanced microprocessor applications used in modern relays, overcurrent protection has been at the heart of the power system for centuries.
Electric Motor Nameplate Ratings Explained. Photo: TestGuy
An electric motor is the workhorse that converts electrical energy into mechanical energy using the principles of electromagnetism. These rotating machines are used in nearly every form of modern life from simple residential appliances to large industrial facilities and manufacturing plants.
Designing, installing, and troubleshooting of electrical systems requires the use of various drawings to give engineers, installers, and technicians a visual representation of the systems they work with.
Electrical equipment and circuitry is often expressed as symbols and lines that represent the various components and connections within a system. The level of complexity within an electrical drawing will vary depending on the intended purpose and personnel working with the drawing.
In liquid filled transformers and other power distribution equipment, the fluid inside is the lifeblood that serves both as a dielectric and a cooling medium. Insulating liquid can be found in many different types of apparatus, including transformers, tap changers, circuit breakers and switches.
Which insulating liquid is chosen for a particular application depends on the required performance and installation of the equipment. For example, an indoor transformer application would call for an insulating liquid less prone to fire hazards whereas equipment located outdoors might call for a liquid with better cooling properties.
Various tests can be conducted on high voltage circuit breakers to evaluate the operational performance of their different internal components. Photo: TestGuy.
Circuit breakers are some of the most complex and critical mechanical components contained within the electrical power system. They are responsible for interrupting nominal and short circuit currents in addition to performing routine changes in the overall system configuration.
Various tests can be conducted on high voltage circuit breakers to evaluate the operational performance of their different internal components. Regardless of the breaker type - whether it be air blast, oil, vacuum, or gas - its important to test their components regularly to help ensure proper operation in case of a system fault or switching operation.
This guide covers the basic theory and applications of power quality monitoring and analysis. Photo: TestGuy.
There are a number of ways in which electric power can be of poor quality. Improper wiring, incorrect grounding, and unbalanced loads are just a few examples of conditions that can produce electrical noise through an electrical system and compromise power quality.
This guide covers the basic theory and applications for Magnetron Atmospheric Condition testing of vaccum interrupters. Photo: TestGuy.
Vacuum interrupters have been used extensively in modern electrical systems to replace older air-magnetic and oil interrupters for circuit breakers rated 1kV-36kV due to their compact size, faster operating speeds, and higher life expectancy.
Although the service life of a vacuum interrupter is the longest of any other interrupting method, they can still catastrophically fail at anytime resulting in extensive downtime. For this reason, field testing of vacuum interrupters is often used to detect and prevent problems that could eventually lead to equipment failure.
There are many different types of power system study, each with their own special purpose and calculation method. Photo: United States Air Force (CC).
Power system studies are essential tools in understanding the expected performance of an electrical system and determining the severity of a fault or other unexpected event.
The data contained within a power system study can be used to safeguard workers by calculating the level of personal protective equipment involved and reduce damage to equipment by optimizing the fault clearing capabilities of protective devices.
Sharpen your skills with our collection of quizzes on electrical safety, maintenance & testing of electrical equipment and industry standards.
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