What is Three Phase Energy Meter？DefinitionA three - phase energy meter is an instrument designed to measure the power of a three - phase electrical supply. It is constructed by connecting two single - phase meters via a shaft. The total energy consumption is determined by summing the readings of both elements.Working Principle of Three - Phase Energy MeterThe torques generated by the two elements are mechanically combined. The total rotation of the shaft is directly proportional to the energy c

Definition：An earth tester is an instrument designed for measuring the resistance of the earth. In a power system, all equipment is connected to the earth via an earth electrode. The earth plays a vital role in safeguarding both the equipment and personnel from fault currents. The resistance of the earth is extremely low, allowing the fault current passing through the earth electrode to be safely dissipated into the ground, thus protecting the power system from damage.Earth electrodes are also c

Definition：An ammeter shunt is a device that offers a low - resistance path for the flow of current. It is connected in parallel with the ammeter. In certain ammeters, the shunt is built - into the instrument, while in others, it is externally attached to the circuit.Reason for Connecting the Shunt in Parallel with the AmmeterAmmeters are designed to measure low currents. When it comes to measuring heavy currents, a shunt is connected in parallel with the ammeter. Due to its low - resistance pat

A potential or voltage transformer is a step - down transformer employed to transform high - voltage values into fractional values. Measuring instruments such as ammeters, voltmeters, and wattmeters are designed for low - voltage operation. Connecting these measuring devices directly to high - voltage lines for measurement can cause them to burn out or be damaged. Hence, a potential transformer is used for measurement purposes.The primary windings of the potential transformer are directly linked

Definition: A temperature transducer is an electrical device that converts thermal energy into physical quantities such as displacement, pressure, or an electrical signal. Its primary function is to enable the automatic measurement of temperature. The fundamental principle underlying a temperature transducer is to detect heat and then convert this information into a readable format for transmission.​Characteristics of the Temperature Transducer​The input is invariably a thermal quantity.​Transdu

DefinitionAn electrostatic instrument is a device whose operation is based on the principle of attraction or repulsion between electrodes carrying electrical charges. In other words, it is an instrument that utilizes the static electric field to generate the deflecting torque. Electrostatic instruments are employed for measuring both high and low voltages, as well as the power in a given circuit.Working PrincipleThe electrostatic instrument operates on the principle of mechanical interaction bet

During the switching of normal load or short-circuit current, SF₆ molecules are ionized and fragmented by the arc. The figure illustrates the main reaction processes and the locations where each process is likely to occur. SF₄, as the primary decomposition product resulting from the electric discharge, first reacts with H₂O on the inner wall surface, giving rise to SOF₂. The metal fluorides remain in the form of powder or dust on the surface. H₂O is released in this reaction and thus becomes ava

For intelligent switchgear, the opening time is defined as the duration starting from the moment when the first message carrying the trip command (a GOOSE message in accordance with the IEC61850 series) is received through the interface, with the circuit - breaker initially in the closed position, and ending at the instant when the arcing contacts of all poles are separated.Regarding the closing time of intelligent switchgear, it refers to the time span from the reception of the first message co

This test serves to ascertain the length and condition of the current - carrying section of the arcing contacts within SF6 circuit breakers. DRM (Dynamic Resistance Measurement) tests are carried out by passing DC current through the breaker's main contacts during the breaker's operation. Subsequently, the breaker analyser computes and plots the resistance as a function of time. When contact movement is concurrently recorded, the resistance at each contact position can be determined. Through DRM

Three Phase WattmeterDefinition: A Three - Phase Wattmeter is an instrument employed for measuring the power in a three - phase circuit. In a three - phase Wattmeter, two individual Wattmeter elements are integrated within a single housing. Their moving coils are positioned on the same spindle.Three - Phase Wattmeter StructureA three - phase wattmeter consists of two elements. Each single element is a combination of a pressure coil and a current coil. In the wattmeter, the current coils are rega