Answer / manoj sharma

We can easily measure AC currents by AC ammeters as AC
currents can be stepdown by current transformer and 0-1 A
current can easily be measured by ammeters. But in case of
DC current it can not be step down. For this a shunt (A
high resistance in parallel of the sorce) is used to reduce
the dc current. As you already know the source voltage,
I=V/R, this will give current through the resistane. at the
same time you knoe resistance of the wire in which high DC
current is flowing. V1=V2(In parallel arrangement)hence
I1=V2/R1. now Ammeter can be calibrated to show the current
R2/R1 times of it.Where R2 is the shunt resistance and R1
is lead resistance across which ammeter and shunt are
installed.

Answer / avd

DE current is measured through shunt. Shunt is a standered
low resistance. It is used in series in the circuit. Due to
series circuit, load current flows through shunt. Because
of this there will be a millivolt drop across the shunt
(ofcource depending on the current). This millivolt drop
across the shunt is measured and meter is calibrated in
terms of current.

Answer / mr.sharif

The simplest way to measure DC current is by using DC
ClampMeter/Multimeter.

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