[F2 IS / NSS Phy] Inside an ammeter and a voltmeter
Have you ever think about how does an ammeter / a voltmeter work?
According to your prior knowledge, you should know that an ammeter should be connected in series while a voltmeter should be connected in parallel. Have you ever ask why about it?
In this post, we are going to ‘open’ an ammeter and a voltmeter in order to have a better understand how does it work!
Dialogue on facebook about X in the diagram:
Supplementary info about X: (Source: Blue Sea Systems)
How a Shunt Works. It is useful to think of water flow in a pipe when thinking about current flow in a wire. The way that a shunt works is analogous to a restriction to the flow of water in a pipe and a bypass around the restriction. Some of the water flow in the Main Pipe is diverted through the Bypass. A Paddle Wheel in the Bypass measures the water flow through the Bypass. If the Bypass allows 1/100th of the water in the main pipe to flow through it, and the Restriction allows the remaining 99/100ths of the water
to flow through it, the ratio of flow in the Bypass to the Restriction is 1 to 99. Using this ratio, the Paddle Wheel could be calibrated to indicate the total flow through the Main Pipe.
A DC ammeter and shunt works in a similar way—a small amount of current that flows through the main wire is diverted to, and measured by, the meter.In order to obtain an accurate reading of the current flow through the main wire, the shunt and meter arevery precisely calibrated at fixed resistance values.
Dialogue on facebook thickness of wire:
Ammeter should be connected in series, voltmeter should be connected in parallel, why? (Source: Department of Physics and Astronomy, Georgia State University )
(to be continued…)
Keyword(s): ammeter, current, electricity, measurement, parallel, resistance, resistor, series, shunt, shunt resistor, voltage, voltmeter
