How to test amperes with a multimeter? Instructions

A multimeter is a device with which the voltage, current, resistance is measured, the wires are "rung". That is, this device is quite in demand. And, as practice shows, it enjoys sufficient popularity not only in industry, but also in everyday life.

But before proceeding to the necessary measurements, it should be noted that the multimeter is not quite a harmless device. With improper use, you can not only easily disable it, but also cause serious harm to your health. This is especially true when you need to measure at high voltage or high current. You can not only burn the multimeter right away, but also get a serious electrical shock.

That is why, before using the multimeter, it is necessary to practice on power supplies with low current indices, for example, on batteries. Also, do not neglect the instructions to the device.

Varieties of multimeters

First of all, you should know that multimeters are digital and analog (switchboards, even among electricians they are known as "shops"). The latter are known to electricians for a long time, but it is rather difficult to use them without special knowledge and practice.

• It is necessary to be able to understand the scales of the device, which are several on the arrow multimeter;
• The device should be kept in such position, when the arrow on it will not "walk" on a scale.

That's why, if there is such an opportunity, it is better to use a digital multimeter. We will also consider examples using a digital device, since it is quite difficult to learn how to work with analog multimeters.

There are many variations of digital multimeters, but the principle of their operation is similar to each other - the difference consists only in the number of functions of the device. Accordingly, the functionality of the multimeter depends on the price, so before you buy it, decide what you need it for.

The multimeter consists of:

• The device itself;
• Two probes (black and red);
• Power supply (9 V battery).

So, what are the features of using this measuring instrument and how to test amps with a multimeter?

Instructions

In order to measure the current in the circuit, it is necessary to connect the device to it in series. At the same time on the multimeter, you need to insert a red test lead into the socket on the device with the inscription mA, and black - in com. Serial connection means that the circuit must be disconnected and each probe connects to a different wire, i.e., the device must be connected between two power supplies. But since you measure the current, and in power supplies it is simply impossible to do, you need to include in the circuit of some device, such as a regular light bulb, placing it in the circuit immediately after the power source.

If you measure the AC power, the maximum AC value is set on the device (A ~ icon - note that it is very similar to the DC icon (A-), so be careful). And only after that you can start measuring.

Before checking the ammeters with a multimeter, make sure that the strength of the measured current is not too high, since such measurements can be unsafe due to the small cross section of the probe wires. The latter can not withstand high loads. Specialists recommend measuring at a current value of more than 10 A by electrical clamps.

Multimeter battery test

The test must be carried out only under load. Check how many amperes in the battery are multimeter, Only with Using the internal capacity of the battery is not possible because of its small value - the obtained indicators do not display the true figures.

It is possible to measure not only the operating current, but also the leakage current of the battery. Before you check with a multimeter, how many amperes make up the leakage current, you need to remember that it can reach up to several amperes. Therefore, it is necessary to set the measurement limits on the device correctly, preferably to 10 A.

In practice, before testing the ammeters on the battery with a multimeter, the positive wire should be flipped from the battery terminal and the measuring device must be inserted in the resulting rupture. Then you need:

• Select on the multimeter the mode for measuring the amperage;
• Fix the "crocodiles" wires and alternately pull out the fuses that are responsible for the electronic module in the car.

With some practice, you will not only know how to test amps with a multimeter, but you can easily detect the causes of the leak without contacting the service center.

Checking the charger

Before answering the question: "How to check ammeters with a multimeter on a charger?", It is necessary to know that you can measure, in principle, any charging. It can be from phones, tablets, memory for a car battery, and so on.

Phone charger

Such measurements are most often needed when it is necessary to identify the cause of the failure of the memory. It should be noted that the current strength on chargers of phones, tablets, etc. differs slightly and is usually indicated on the charging sticker or labeling. But if for some reason there is no such inscription, then you can check this figure with a multimeter.

The principle of measuring the amperage in the charger can differ only in that it is rather difficult to connect a meter to it because of the small size of the contacts on the connector. To do this, it is necessary to carefully insert the usual steel sewing needles into the contacts and connect the meter probes to them. If this can not be done, the only way out is to open the charger body in order to connect the probes directly to the terminals of the memory in the place where the ends of the electric cord are soldered.

Battery charger for car battery

Before talking about how to test amps with a multimeter for storage for a car battery, you need to know what it's for.

The optimum value of the charging current of such a memory is 10% of the capacity of the vehicle's battery. A large amount will allow faster charging of the battery, but it will negatively affect the battery itself and significantly reduce the time it is used.

When purchasing such a memory in the store, all parameters are registered on the charger itself. But such a charge, with minimal knowledge, can be done independently. In this case, you will need a multimeter. Also, this measuring instrument is useful if the charger fails.

It should be said that when measuring the current strength of any chargers in the circuit, it is necessary to include any load (for example, a normal light bulb). Also do not forget that often the charger outputs a constant current, so the multimeter handle must be set to the correct position (A-).

Power unit check

How to test amps with a multimeter on the power supply? This is also done to break with the mandatory application of the load. The principle itself differs little from the verification of other sources. It only needs to be noted that the PSUs have a rather high power, so measurements should be carried out quickly, not allowing heating of the wires of the test leads of the multimeter.

As we can see, the multimeter can be very useful in everyday life and is in demand in completely different areas, therefore getting the most minimal knowledge on its use will not be superfluous.