Skip to main content

Split core CTs and why size matters


Current Transducers
Current Transducers (CTs) ar a essential element of power observance. They come during a style of formats, sizes, current ratings and accuracy levels. The side we'd wish to concentrate on here is size, specifically inside diameter.
The inside diameter (ID) is the width of the opening in the CT that the conductor goes through. It must be large enough to fit around the conductor, however choosing too large of a CT can create other issues. As the graphic above indicates, the overall dimensions of the CT grow substantially as the ID gets bigger.

Current Transducer Types

Current sensors can be either open-loop or closed-loop.
Open-Loop Sensor: This type measures AC and DC currents and provides electrical isolation between the circuit being measured and the output of the sensor. Open-loop current sensors are generally preferred in battery-powered circuits.
Closed-Loop Sensor: The Closed-Loop sensor is sometimes called a ’Zero-Flux’ sensor because it features a Hall-Effect sensor that feeds back an opposing current into a secondary coil, wound on the magnetic core to zero the flux produced in the magnetic core by the primary current. Closed-loop sensors are often used when high accuracy is essential.
Current rating
Be sure to use a CT with a current rating as close to the actual current being monitored as possible to maximize accuracy at the lowest possible load. ACT will be accurate across some portion of its range.
Inside diameter
CTs of the same amperage come in different sizes. For example, RS Components offers 200 amp CTs with 24mm, 36mm and 50mm IDs. The chart below shows that a 200A CT with a 50mm ID is much larger than one with a 24mm ID. Since space inside electrical equipment is often tight, using a CT that is larger than needed can create problems as well.
CT sizing summary
Most customers will try to match the amperage of the Current Transducers to the rating of the over-current protection on the circuit. You need to know both the circumference of the conductor(s) that the CT has to fit around (to determine the minimum acceptable ID) and the amount of available space in the panel where the CTs will be installed. If the conductor is very large or the space is particularly tight, a Rogowski coil ("rope CT") might be the best choice.

Labels:

Comments

Post a Comment

Popular posts from this blog

Different types of Limit Switches

Rotary Geared Limit Switches The operating of the Limit Switch is to prevent the mechanism or drive at the intense forward/reverse positions. The Limit Switches are significantly suited to use on reversing drives like a hoist, winches, rolling mills and various other mechanisms used in steel plants such as coke ovens, feeding machinery, valve drives etc. The contacts of Limit Switches are forty amps rated ceaselessly at 500 Volts A. C. The Limit switch is often supplied with two NC contacts or four NC contacts or (2 NO + two NC) contacts as per the need. For Series Limit Switches are shields are provided. The frequency of switching of each contact is suitable for a maximum of 720 operations per hour. The speed of the driving shaft rotation shouldn't be over 60 rpm. Features:- High durable standards Optimum performance Easy to install Counter Weight Limit Switches A metal structure offers the required stability to Counter Weight Limit Switches that job on heavy c...
Post a Comment
Read more

What is Solar Panels? How Does a Solar Panel Work?

Solar Panels Photovoltaic (PV) is the term identified with the change of light into power utilizing semiconducting materials that display the photovoltaic impact. A typical use of this technology is solar panels which comprise of solar cells that generate solar power. They can be installed on south-facing roofs, walls or on the ground, and can be fixed or have a solar tracker that follows the sun across the sky. The installation of solar panels is very beneficial for both private and commercial users because the solar power became electricity will be sold to the energy supplier. The feed-in tariff can reduce energy bills and price of solar panel installation. The advantage of this type of energy source is that it is clean energy, so generates no pollution and no greenhouse gas emissions. It is however dependent on direct sunlight so around 10% to 25% is lost when a tracking system is not used. How Does a Solar Panel Work? The solar cells within a solar array produce DC elect...
Post a Comment
Read more

What is TVS Diodes: - Types, Working and Advantages & Disadvantages

TVS Diodes Transient voltage suppressor diodes, more commonly referred to as TVS diodes  are wont to protect integrated circuits (ICs). TVS diodes ensure semiconductors and delicate parts against high transient voltage spikes (overvoltage). TVS diodes are offered in both through-hole and surface mount bundles. They can be unidirectional or bidirectional. Unidirectional TVS diodes will only allow positive or negative voltage whereas bidirectional diodes can operate at both positive and negative voltages. TVS diodes are able to conduct large currents to the ground due to their construction. They feature a way larger p-n junction cross-sectional area than standard diodes. Types of TVS Diode Transient Voltage Suppressor Diodes can be grouped into two kinds. One is Unidirectional , and the other is Bidirectional . A unidirectional Transient Voltage Suppressor Diode fills in as a rectifier in a circuit the forward way like some other avalanche diode, and this unidi...
Post a Comment
Read more