Meter Movement

Question: Describe the type of movement used in analog meters

Answer:

The D'Arsonval movement is a DC moving coil-type movement commonly used in voltmeters, ammeters and ohm meters. An electromagnetic core is suspended between the poles of a permanent magnet as seen in the image below.

In an ammeter, current passes through the coils of the electromagnet (current path not shown in the figure). This current produces a magnetic field that opposes the magnetic field already set up by the permanent magnet in the figure. The stronger the current, the stronger the magnetic field, and the larger the pointer deflection. If current is no longer flowing, the upper and lower control springs will bring back the pointer to its default position for a zero current reading.