Simple Galvanometer Diagram. Moving coil galvanometer construction and diagram. Ac generators work on the principle of faradays.
The same galvanometer can be used for measuring current when it is converted into an ammeter by connecting a small resistance r sh in parallel with the meter as shown in the figure. A very simple galvanometer may be made from a magnetized needle such as the needle from a magnetic compass suspended from a string and positioned within a coil of wire. A simple needleless galvanometer is presented in this tutorial.
Suppose you want 10 v to produce a full scale deflection of a voltmeter containing a 25 ω galvanometer with a 50 μa sensitivity.
Current through the wire coil will produce a magnetic field which will deflect the needle from pointing in the direction of earths magnetic field. Some of such devices have arbitrary scale values sometimes with variable gain and are designed simply as balance indicators. The ac generators input supply is mechanical energy supplied by steam turbines gas turbines and combustion engines. A jockey is connected at the other end of the galvanometer here a jockey is a metal rod with a knife like edge at one end slides over the potentiometer wire to make an electrical connection.