How to measure tension and current

How to measure tension and current

For measurement of current in an electrical circuit the ampermeter is used, and tension is measured by means of the voltmeter. At the same time the ampermeter turns on consistently with loading in chains, and the voltmeter – parallel to a source of electric energy.

It is required to you

  • - milliamperemeter;
  • - voltmeter.


1. Prepare measuring devices for work. Arrange them in the horizontal position convenient for use. Establish the zero provision of a scale by means of the proofreader. Connect measuring cables to the corresponding terminals of the milliamperemeter and the voltmeter. Install switches of devices on the biggest measurement range. Ground devices of measurements and connect them to an electrical network.

2. Choose the voltmeter mode for measurement of constant or variable values. To measurement of constant tension there corresponds inscription DCV or V on a measuring scale of the device. Measure constant tension on battery poles (accumulator terminals, the outputs of the power supply). For this purpose connect the positive terminal of the device a red measuring cable (wire) to a positive pole of the battery (accumulator), and negative – a black cable to a negative pole. Reduce a limit of measurements until receive the required accuracy of measurements.

3. Measure the alternating voltage of an electrical network (site of a chain). To measurement of variable tension there corresponds the inscription ACV or V ~ a measuring scale of the device. The order of connection of terminals of measuring devices with different polarity at measurement of variables, does not play any role.

4. By analogy with voltage measurement measure direct and alternating current in an electrical network. At the same time the scheme in which the milliamperemeter is connected has to be previously opened, and the device has to be switched on after loading.

Author: «MirrorInfo» Dream Team