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This blog category explores current transformers (CTs), covering their working principles, types, applications, and advancements. It includes insights on installation, testing, troubleshooting, and modern innovations like digital CTs and Rogowski coils. Industry professionals can find technical discussions, case studies, and comparisons on how CTs enhance power monitoring, protection systems, and energy efficiency in industrial and smart grid applications.
A high-voltage power system deals with a huge quantity of currents. Unfortunately, the huge size of meters or protection relays is not available in the market. For cost and size optimization, the meters and relays are normally designed with a 1 A or 5 A rating. Therefore, there must be some means by which we … Read more
The current transformer is a kind of transformer that steps down currents. From the name “current transformer,” we can understand that it deals with current. The available instruments for measuring and protection purposes in the market are of a few amperes range. The ammeters, energy meters, wattmeters, and various protection relays are rated for only … Read more
In this article, we are going to discuss the dead tank CT or dead tank current transformer, commonly referred to as a dead tank CT. Dead tank current transformers are not popular for very high-voltage systems like 220 kV and above. Utilities often use dead tank CTs in 33 kV systems. They prefer this design … Read more
When it comes to high-voltage power systems, current transformers (CTs) play a critical role. It has a vital role in measurement and protection. CTs come in two main designs—Live Tank and Dead Tank. While both serve the same fundamental purpose, they differ significantly in construction. Live tank and dead tank CTs differ mainly in insulation. … Read more
Current Transformers (CTs) play a crucial role in power systems. They perform both metering and protection functions. However, the same CT can not perform both metering and protection functions. This is because each of the protection and metering applications has different accuracy, burden-handling, and dynamic performance requirements. Hence, CTs are designed as either Metering CTs … Read more
A current transformer (CT) reduces high currents to small, usable values. We utilize CTs for metering and protection purposes. Proper CT selection ensures accuracy, safety, and reliable protection. Identify the Purpose of CT Metering CT A metering CT measures current for billing and monitoring. Therefore, it must work accurately within the tolerable upper limit of … Read more
Current transformers (CTs) play a critical role in protection and metering. The proper operation of protection relays depends on CT accuracy to detect faults. Additionally, the accuracy of CT is more important for metering purposes. However, when a CT experiences core saturation, its secondary output no longer represents the true replica of the primary current. … Read more
A critical component of a CT is its magnetic core, which significantly influences its performance, accuracy, and efficiency. Accuracy is the most essential property of a current transformer. Traditionally, Cold-Rolled Grain-Oriented (CRGO) silicon steel has been the material of choice for these cores. Nowadays, a superior alternative is available on the market—nanocrystalline core material. In … Read more
Nowadays, SF6 gas-filled current transformers become popular modern type of CT used in high-voltage substations. It uses SF6 gas as its internal insulating medium instead of conventional insulating oil. We normally install SF6 CTs in voltage levels above 132 kV. A typical SF6 CT is a single-unit, live-tank type instrument transformer. Because it contains pressurized … Read more