Definition: The tachometer use for measuring the rotational speed or angular velocity of the machine which is coupled to it. It works on the principle of relative motion between the magnetic field and shaft of the coupled device. The relative motion induces the EMF in the coil which is placed between the constant magnetic field of the …
The DC potentiometer method of measurement of resistance is used for measuring the unknown resistance of low value. This can be done by comparing the unknown resistance with the standard resistance. The voltage drop across the known and unknown resistance is measured and by comparison the value of known resistance is determined. Let understand this …
The power which exists in the circuit when the voltage and current are out of phase to each other, such type of power is known as the reactive power. The formula measures the reactive power in the circuit The measurement of reactive power is essential because the value of reactive power shows the total power …
The calibration is the process of checking the accuracy of the result by comparing it with the standard value. In other words, calibration checks the correctness of the instrument by comparing it with the reference standard. It helps us in determining the error occur in the reading and adjusts the voltages for getting the ideal …
Calibration of Voltmeter, Ammeter & Wattmeter using Potentiometer Read More »
Definition: The photoelectric transducer converts the light energy into electrical energy. It is made of semiconductor material. The photoelectric transducer uses a photosensitive element, which ejects the electrons when the beam of light absorbs through it. The discharges of electrons vary the property of the photosensitive element. Hence the current induces in the devices. The …
Definition: Hygrometer uses for measuring the humidity present in the surrounding environment. The term humidity means the amount of water vapour present in the gas. The physical properties of the material changes by the effect of the humidity and this principle use in hygrometer for measurement. The humidity is classified into two types. Absolute Humidity …
The Schering bridge use for measuring the capacitance of the capacitor, dissipation factor, properties of an insulator, capacitor bushing, insulating oil and other insulating materials. It is one of the most commonly used AC bridge. The Schering bridge works on the principle of balancing the load on its arm. Let, C1 – capacitor whose capacitance …
Definition: The Kelvin bridge or Thompson bridge is used for measuring the unknown resistances having a value less than 1Ω. It is the modified form of the Wheatstone Bridge. What is the need of Kelvin Bridge? Wheatstone bridge use for measuring the resistance from a few ohms to several kilo-ohms. But error occurs in the …
Definition: Three-Phase Wattmeter is used for measuring the power of the three-phase circuit. In three-phase Wattmeter, the two separate Wattmeter are mounted together in the single unit. Their moving coils are placed on the same spindle. Three-Phase Wattmeter has two elements. The single element is the combination of the pressure coil and the current coil. The …
Definition: The multimeter or volt-ohm-milli-ammeter (VOM) is the type of meter which performs the multiple functions. In other words, in VOM the multiple measuring functions are combined in a single unit. The multimeter is used for measuring voltage, current and resistance. It contains the circuitry switch which makes the meter to operate like a voltmeter, …
