Definition: The tachometer which uses the light for measuring the speed of rotation of shaft or disc of machines is known as the photoelectric tachometer. The opaque disc with holes on its periphery, light source and laser are the essential parts of the photoelectric tachometer. The tachometer consists the opaque disc which is mounted on the …
Definition: The maximum demand indicator measures the maximum amount of power requires by the consumer at the particular interval of time. The indicator is designed in such a way so that they measure the base and peak load but unable to measures the sudden short-circuit or starting high current of the motor. It is designed …
Definition: The Hot Wire Anemometer is a device used for measuring the velocity and direction of the fluid. This can be done by measuring the heat loss of the wire which is placed in the fluid stream. The wire is heated by electrical current. The hot wire when placed in the stream of the fluid, …
Definition: The seismic transducer is used for measuring the vibration of the ground. The spring mass damper element and the displacement transducer are the two main component of the seismic transducer. The mass that connected to the damper element and spring without any other support is known as spring mass damper element. And the displacement …
The rating is the load carrying capability of the machine. It shows the maximum value of the voltage at which the machine is designed, and the current consumption occurs at that voltage. The machines are always rated in watts. But the alternator and the transformer are the only machines which are rated in volt-amp (VA). Why …
Definition: The inductor is a passive component which stores the electrical energy in the magnetic field when the electric current passes through it. Or we can say that the inductor is an electrical device which possesses the inductance. The inductor is made of wire which has the property of inductance, i.e., opposes the flow of …
The Carey Foster Bridge is used for measuring the low resistance or for the comparison of two nearly equal resistances. The working principle of the Carey foster bridge is similar to the Wheatstone Bridge. The circuit for the Carey foster bridge is shown in the figure below. Let P, Q, R and S are the …
Definition: The platinum thermal resistance (PTR) uses platinum for determining the temperature. It works on the principle that the resistance of platinum changes with the change of temperature. The thermometer measures the temperature over the range of 200°C to1200°C. The platinum is an unreactive metal and can easily be drawn into fine wires. Because of these properties …
Definition: The Photovoltaic cell is the semiconductor device that converts the light into electrical energy. The voltage induces by the PV cell depends on the intensity of light incident on it. The name Photovoltaic is because of their voltage producing capability. The electrons of the semiconductor material are joined together by the covalent bond. The electromagnetic …
Definition: The bimetallic thermometer uses the bimetallic strip which converts the temperature into the mechanical displacement. The working of the bimetallic strip depends on the thermal expansion property of the metal. The thermal expansion is the tendency of metal in which the volume of metal changes with the variation in temperature. Every metal has a …
