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A surge protection device (SPD) or simply a surge protector is a device used to ensure protection against transient surges. It is used to protect the household and commercial applications from voltage transients. It is connected in parallel to the load it has to protect. What is a transient surge? A transient surge is a … Read more
Several operating indications can be seen on the front of an ACB or MCCB. Being an electrician or an engineer it is important that one must understand those indication and circuit breaker positions. Each of those indications has some critical information regarding the current state of the circuit breaker. The following are the three most … Read more
RCCB stands for Residual current circuit breakers and MCB stands for Miniature circuit breakers. Both of them are basic circuit protection devices found in the distribution boards of every house and commercial lighting power distribution boards. Here are the differences between MCB and RCCB. RCCB – Residual Current Circuit Breakers Residual current circuit breakers are … Read more
Potential transformers (PT) or voltage transformers are instrument transformers used for voltage measurements. They are connected in parallel to the line and operates under the same principle of power transformers. They cannot be used used to supply raw power to the loads. They have an accurate voltage ratio and phase relationship between primary and secondary … Read more
What is a current transformer? A current transformer is a type of instrument, used to measure or sense large alternating currents by scaling it to a smaller, safer and measurable value. It transforms the primary current to a proportional secondary value in terms of magnitude and phase. Current transformers are available in various sizes and … Read more
Induction motors are robust and reliable and are used in all industries across the globe. Various methods are followed to start induction motors, out of which star-delta starters are the most commonly used ones to reduce the starting current. Star-delta starters are cheaper than soft-starters and are widely seen in small-scale industries. Typically, star-delta starters … Read more
What is switchgear? Any mechanical switching devices used to make or break the current flow and their combination with measuring and control devices are known as switchgear. This includes circuit breakers, contactors, isolators, fuses, relays etc. This articles intents to describe the different switchgear in short and their switching phenomena. Circuit breaker A circuit breaker, … Read more
Circuit breakers are employed to automatically switch off a circuit or a load whenever any abnormalities in current flow are detected. This functionality of the circuit breakers is known as ‘Trip’. By doing so, circuit breakers are preventing fire or other damages caused to the circuit. Here are the major reasons behind your circuit breaker … Read more
Overhead transmission lines are not insulated primarily due to three reasons: first and foremost is to reduce the weight of the lines, secondly to save cost and the last is they are at sufficient height to avoid direct contacts. Let us discuss each one of the reasons one by one elaborately. You might have notices … Read more
The utilization categories AC-1 and AC-3 defines making, breaking and continuous operation current rating for contactors. Based on these rating, contactor for switching of resistive loads and switching of squirrel cage induction motor are selected. The above picture shows a contactor manufactured by ABB with its operational current rating labelled on it. It can be … Read more
