Electrical measuring instruments

Range Extension of Ammeter and Voltmeter

There is no fundamental difference in the operating principles of ammeters and voltmeters. Both are current operated devices (except electrostatic type voltmeters) i.e. deflecting torque is produced when current flows through their operating coils. In an ammeter, the deflecting torque is produced by the current to be measured or by a definite fraction of it whereas …

Range Extension of Ammeter and Voltmeter Read More »

Deflecting Torque | Controlling Torque | Damping Torque

In order to ensure proper operation of indicating instruments, the following three torques are required: Deflecting Torque | Controlling Torque | Damping Torque  One important requirement in indicating instruments is the arrangement for producing operating or deflecting torque (Td) when the instrument is connected in the circuit to measure the given electrical quantity. This is achieved …

Deflecting Torque | Controlling Torque | Damping Torque Read More »