In this video, the presenter would be explaining how to properly apply Current Transformer considering accuracy, types, safety, temporary and permanent applications.
The description given below is the short transcript of the video given in the article.
A current transformer (CT) is a current measuring device used to safely reproduce a low-level current that accurately represents a higher current level for the purpose of metering or protection.
How does Current Transformer work?
The most common way to calculating and measuring current using the current transformers by applying Maxwell’s equation especially amperes law we can say that if a magnetic field is integrated around a closed loop of wire, the value of that integral is equal to the net current enclosed by the loop.
Current transformers are closed-loop instruments consisting of a magnetic core and a secondary winding around the core. The primary winding of the CT, the main loop has the wire with the current we wish to measure pass through the center of the core.
The primary winding that carries the main current is said to have a single loop for winding. The wire produces the magnetic field that drives the current on the secondary winding which is used as the output of the current transformer.
The current on the secondary winding is proportional to the current flowing through the center of the core.
Typically the secondary winding carries 5 amps or 1 amp.
Current transformers are used extensively in metering and circuit protection.
Current Transformer Types
The Current Transformers come in various sizes, shapes and ratings. Current Transformers can be Solid Cords, Split Cords or clamp-on styles.
- Solid cords are generally more permanent and are found in switchboards, Panelboards and switchgear.
- Split cords or clamp-on Styles are used in Power quality instruments.
Current transformers are generally found in Generators, transformers and connected loads for monitoring the current flowing in the system.