The multimeters are equipped with two probes that are used to carry out the measurement. The probes and cables are usually black and red. The colors indicate the polarity of the measuring lead. However, they are usually also additionally labeled. Red stands for plus and black for minus. Depending on the manufacturer, there are also other connection options and, for example, a temperature sensor can be connected.
If you now want to measure the voltage of a car battery, you must hold the probes to the respective poles of the battery; the red probe to the positive pole and the black probe to the negative pole. Depending on the model, you can now read the voltage on the display or the analog display.
Hint: Caution should be exercised if you want to check a socket with the multimeter. Here, the multimeter must be set to alternating current in advance.
If you want to measure with the multimeter of electricity, this project is a bit more complex. In order to be able to measure current with the multimeter, it must be integrated into the circuit. To do this, the circuit must first be opened and the multimeter closed in between. Then select the appropriate measuring range in order to be able to measure amperes with the multimeter.
If a negative value is displayed when the device is switched on, the lines must be replaced.
How is a multimeter operated?
Multimeters are equipped with a battery. Depending on the measurement, the battery serves as a power source and no additional power supply is required. According to various multimeter tests on the Internet, this is usually a 9 V block.
History: The predecessor of the multimeter was invented in the 19th century
The first current meter was invented in 1820 and is considered the predecessor of today’s multimeter. The galvanometer, as the meter was called, weber summit 470 specification detected electric current and then moved a compass needle. Due to its size, however, it was not suitable for everyday use.
If you want to buy a multimeter that suits your needs, you should not be guided by brand names, but take a look at the following points:
Measures: Which ones are available?
The multimeters usually allow use in different measuring ranges. Among other things, the following measured variables are distinguished:
Voltage: In this area, a distinction is made between DC and AC voltage. Conventional multimeters are suitable for measuring DC voltage from 0.2 to 1,000 volts and AC voltage from 2 to 700 volts. Decisive for this is the CAT standard.
Current: The measuring range here is usually 0.2 mA to 10 A. However, this value is only required for direct current.
Resistance: Common multimeters can perform resistance measurements between 200 ohms and 200 kiloohms.