How to connect an ammeter?

What is a direct current ammeter? This magnetoelectric indicator and shunt, which is a powerful resistor of small resistance. Due to the lack of a rectifier, the characteristic of this ammeter approaches linear.

In this article we will tell you how to connect the ammeter correctly.

• From the very beginning we want to warn that the shunt forammeter should be included in the delivery of this device. If you take another, this can lead to the fact that the testimony will be given incorrectly. What is the reason for this? First of all, even with indicators of different brands with the same current of total deviation, the shooters may have different internal resistance.
• Now select the shunt for the ammeter, the limitingthe current of which will be lower than that measured. Suppose, if it is assumed that the current in the circuit will fluctuate within the following limits - from 5 to 8A, then you need to select a shunt at 10A.
• On the screws of the device you will find two nuts. With each of the screws, unscrew the first of them, and the second one, which is closer to the body, is not necessary to turn, otherwise the screw will fall inward, and the ammeter will have to be opened.
• Now put the screws on the screws and tighten them with nuts. There must be two washers between the shunt and the second nuts that are located on each of these screws, do not forget about it.
• The circuit for connecting the ammeter is as follows: you must disconnect the device from which you want to measure the current consumed. Simply tear the circuit of its supply, and then, observing the polarity, the ammeter is included in the circuit with the shunt. Wires at the same time clamp honey with washers. After performing these actions, you can turn the power back on by reading the readings, and then again disconnect the circuit, remove the ammeter and reconnect.
• Multiply the instrument reading by a factor,which is indicated on the shunt. If there is no such data, you can calculate the division price yourself. How to do it? Here is an example - if the current with a full deviation of the indicator is 100 μA, and the shunt is rated at 10 A, then each microampere on the scale will correspond to 0.1 A of current in the circuit.
• At worst, you can use a shuntwithout designations, and also by any magnetoelectric indicator. Consistently connect the test and the standard ammeter and then safely connect them to the current stabilizer. Gradually increase the current from zero, so you must achieve a complete deviation of the arrow of the device under test. Thus, a model ammeter will help you to know the current value in the circuit. Divide this value by the number of divisions that are on the scale, this will help to calculate the price of one division.

Now you know how to connect an ammeter, we hope that you will be able to use the proposed instructions in practice.