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here is a picture of a multimeter:

enter image description here

the display shows: 02,0
is it 2A or 2mA ?

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    \$\begingroup\$ Note, if you were trying to measure 2A, you should be using the top current socket. The one the red probe is in is marked "200mA max" - something inside is not designed to take more than 200mA on that socket (you cannot assume cheap meters are fused). \$\endgroup\$ Mar 7, 2013 at 20:18

3 Answers 3

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The range switch on the front of the multimeter shows the maximum current that can be measured on that range. The range switch is pointing at the "200m" DC Amps range in the picture. Therefore, the full-scale readout for this range will be about[1] 200 milliamps. If more than 200 mA of current passes through the multimeter on this range, the multimeter will display an over-range indicator instead of the measured current. This means that a display of "2.0" or "2,0" indicates a measured current of 2 milliamps, not 2 amps.

Also, notice that there are two sockets on your multimeter for measuring current. One is for use with the milliamp and microamp ranges, while the other socket is for use with the amp range. The milliamp range is fused (notice how only the 5A plug has the label "unfused"). Passing more than 200mA of current through the milliamp socket will blow the fuse to protect the multimeter. That is another way you can tell that you are measuring 2 mA and not 2 A.

[1] The exact full-scale range of many multimeters is not exactly the same as the number printed on the range switch. For example, on a Fluke 77 multimeter, the 300 mV range actually measures up to 303.1 mV before displaying an over-range indicator.

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The setting on the multimeter dial shows the maximum amount you can measure on that setting. It also shows the unit that the measurement will be reported in, since your multimeter isn't capable of displaying units on the display. So, the meter is measuring 2mA.

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It should be "2 mA" since you are on a mA scale. 200m; notice 'm'.

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