An electric current is measured with an instrument called n ammeter.
It is often necessary to know how to measure current using a multimeter. Current measurements are easy to make, but they are done in a slightly different way to the way in which voltage and other measurements are made. However current measurements often need to be made to find out whether a circuit is operating correctly, or to discover other facts associated with its current consumption.
Current is one of the basic electrical / electronic parameters, and therefore it is often necessary to measure the current flowing in the ciricuit to check its operation.
Current measurements can be made with a variety of test instruments, but the most widely used pieces of test equipment for making current measurements is a digital multimeter. These items of test equipment are widely available and at very reasonable prices.
Current measurement: basics
Current measurements are made in a different way to voltage and other measurements. Current consists of a flow of electrons around a circuit, and it is necessary to be able to monitor the overall flow of electrons. In very simple circuit is shown below. In this there is a battery, a bulb which can be used as an indicator and a resistor. To change the level of current flowing in the circuit it is possible to change the resistance, and the amount of current flowing can be gauged by the brightness of the bulb.
When using a multimeter to measure current, the only way that can be used to detect the level of current flowing is to break into the circuit so that the current passes through the meter. Although this can be difficult at times, it is the best option. A typical current measurement can be made as shown below. From this it can be seen that the circuit in which the current is flowing has to be broken and the multimeter inserted into the circuit. In some circuits where current may often need to be measured, terminals with a shorting link may be added to facilitate the current measurement.