How to measure at high amperage
Evaluating the performance of any equipment is possible only with accurate statistics. To collect this data, special devices are used - an ammeter, an electricity meter etc. But if they themselves can not withstand high loads, then how to collect information on the operation of powerful electrical installations? The solution is to use measuring current transformers.
These devices reduce the current strength to the values with which the measuring instruments work (from 0 to 5 A). Moreover, this applies not only to measuring equipment, but also to devices for protecting and controlling an electrical circuit, for example, a variety of relay automation.
Protective and measuring devices are connected to the secondary winding of the current transformer, which is directly connected to the conductor itself. An important technical feature of the current transformer, which ensures measurement accuracy, is the proportional correspondence of the current in the secondary circuit to the current in the conductor.
How to choose a measuring current transformer
When searching for a device in the category of measuring current transformers, the price is usually put first. However, it is important to remember that this is only one of the characteristics that you should pay attention to. The first ones are the quality of the instruments and the magnitude of the measurement error. Responsible tasks, for the solution of which current transformers are used, place high demands on them:
- devices must be made of reliable materials and pass tests successfully;
- as intermediaries between the conductor and the measuring devices, current transformers must comply with high measurement accuracy with minimal error.
EKF current transformers have all these characteristics. Their reliability is confirmed by widespread use both in industry and in the residential sector.
Three series of current transformers are presented in the EKF PROxima line: with a universal window, with a built-in bus and detachable. They are designed to work in AC networks with a frequency of 50 Hz with a rated voltage of up to 660 V.
Devices with a universal window and integrated bus
EKF’s TTE series includes measuring transformers with a universal window - a characteristic hole in the center of the device into which the conductor is inserted. Due to the size of this window, specialists are not limited in the use of a current transformer on buses and cables of only one section.
The TTE assortment includes devices in a wide range of rated primary currents - from 100 to 5000 A. In addition, the TTE current transformer is offered in six dimensional versions, which greatly expands the selection.
Another type of instruments is TTE-A. These are measuring current transformers with an integrated tinned copper bus. Both copper and aluminum conductors can be connected to the device contacts.
In all TTE and TTE-A devices, reliability and safety are of great importance. To prevent access to the secondary winding, their housings are non-separable and sealed. In addition, a transparent cover protects the contact part of the measuring transformers from unauthorized access and prevents accidental contact with live parts of the device.
The most important characteristic of current transformers is the accuracy class, which shows the measurement error. TTE and TTE-A devices have an accuracy class of 0.5 or 0.5S, which are the most popular on the market. It is important to remember that current transformers of class 0.5S are several times more accurate than devices with characteristic 0.5.
Split-core current transformers EKF
In the TTE-R series, devices are presented that are structurally similar to devices with a universal window, but consisting of two separable parts. Due to this feature, they can be installed and removed without disassembling the structure with a conductor, which significantly saves installation time. Detachable measuring transformers EKF are designed for a rated primary current of 150 to 3000 A and are available in several overall versions.
Other measuring instruments
Measuring transformers cannot be dispensed with when it is necessary to “take readings” in a circuit with high currents. But in the EKF product line, there are also various instruments that facilitate measurements in the domestic environment - multimeters and current clamps. They are just as popular with professionals as the tools every electrician needs: screwdrivers, cable scissors, pliers and side cutters.
The EKF product line also includes the electromechanical or electronic energy meter necessary for any apartment. The devices in the SKAT series are compact, easy to install and have a built-in seal to protect against unauthorized access.
Thus, no matter what the tasks facing the specialist, the EKF assortment contains all the necessary devices and tools - accurate, reliable and safe.