Do you want to buy a universal meter or multimeter? With us you can choose from a wide range: from an affordable digital multimeter of less than ten euros to a high-quality Fluke multimeter with high accuracy and many useful extra options.
Note: the cheaper models often do not have an AC current range. If you want to be able to measure alternating current, choose a somewhat more expensive model that does have this option. A set of test cables is supplied with a universal meter with test pins at the ends. Do you need extra test cables with plugs or terminals at the end? Then order it immediately.
Best Digital Multimeters:
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What is a Multimeter?
A multimeter is a versatile measuring instrument with many possibilities. This measuring instrument got its name from the ability to measure different electrical quantities.
A standard universal meter measures the electrical quantities of voltage, current and resistance. When ordering a multimeter, keep in mind that almost any type is suitable for measuring DC current, but only the more expensive types can also measure AC current.
All types measure DC voltage and AC voltage. A more expensive instrument often has more options and is above all a lot more accurate and robust than an inexpensive model. More expensive instruments often have a built-in glass fuse to protect the instrument against overload if connected incorrectly. In the event of an overload, the fuse will melt and must be replaced with a new one of the same value.
In addition to a digital readout, some types have a simulated analog scale, making it easy to assess the voltage variation over time. A special tool is the ampere clamp. This meter allows you to measure the current through the wire without interrupting a wire. The operation is based on the principle that current through a wire creates a magnetic field around the wire.
Measure voltage with a Multimeter
Voltage is the electrical quantity of potential shown in the unit of volts. Voltage is always measured between two points. Think of the two battery poles or the two connection points in a socket.
A battery provides a DC voltage of a few volts. An electrical outlet provides an alternating voltage of around 230 volts. Each universal meter is equipped with the possibility to measure both direct and alternating voltage.
The voltage range of a multimeter ranges from a few microvolts (one-millionth of a volt) to approximately one thousand volts. This is more than sufficient for most applications. To measure DC voltage, turn the dial on the meter to the V symbol with one or two straight dashes. To measure AC voltage, set the rotary knob of a multimeter to the symbol V with the wave. The wave indicates that the meter is measuring AC voltage.
Many types of the universal meter will also be able to measure DC voltage in the AC voltage position, but the measured value will in many cases deviate from the actual DC voltage value.
Measure current
Current is the electric quantity of charge displacement per second and is shown in the ampere unit. An analogy is the amount of water that passes through a water pipe per second. Current flows through a wire.
To be able to measure this, the wire must be disconnected and the universal meter must be connected between the wire and the connection where the wire is normally connected. To measure, set the meter wire knob to the A symbol. Cheap universal meter types can only measure direct current.
More expensive units have the possibility to measure alternating current in addition to a direct current range. The current measuring range of a multimeter ranges from a number of micro amps (one-millionth ampere) to a number of amps. For the higher current ranges, it is often necessary to insert the positive plug in a separate connection of the meter. A meter has a low resistance when measuring.
If you want to measure voltage and the meter is accidentally in a current range, a high current can flow as soon as you connect the meter to a battery or the socket, which can damage your universal meter.
Measure Resistance
Resistance is a passive electric quantity. This reduces the current that can flow at a certain voltage. It is expressed in the ohm quantity.
Many people know this greatness from Ohm’s law. U = I x R, where U is the voltage across a resistor, I is the current flowing through a resistor, and R is the resistance in Ohms. Since resistance is a passive quantity, a source is required to pass a current through a resistor.
A multimeter uses the built-in battery for this. By passing a fixed current through a resistor and then measuring the voltage across the resistor, the multipurpose meter can determine the resistance and show it on the display.
The diode test has a great similarity to the resistance measurement range. The meter sends a fixed current through the connected diode. But the meter displays the measured voltage. This voltage is the forward voltage of a diode and is characteristic of the type of diode. With a silicon diode the knee voltage is 0.7 volts with a germanium diode it is 0.3 volts and with a Schottky diode, it depends on the type 0.15 to 0.46 volts.