To your attention, there are already 74 questions asked by a reader who introduced himself as Gennady. If you have your own answer to the question, then write it in the comments below. I and other readers of my channel will be happy to read it.
I quote verbatim the text of the question itself:
Good afternoon, tell the teapot how to connect the ammeter to the car cigarette lighter to control the battery, where is + -?. Ammeter m42101. If possible, a detailed diagram of Comrade K. kettle!!
I reviewed the issue and advised the reader within the framework of my knowledge and qualifications as follows:
Hello!
Nowhere, the ammeter shows the current strength, if you connect it to the car's cigarette lighter, then on the scale of the device the amount of current consumed by the cigarette lighter will be displayed, but will not help to control the state Battery.
The thing is that the ammeter itself represents the minimum resistance, practically tending to zero, which is why it cannot be connected to the circuit alone, it will simply short-circuit it. Therefore, the ammeter is connected in series with any load, for example, with a charging unit, which shows what current is charging something from your cigarette lighter, in this case the circuit looks like this way:
I understand that you most likely just have such an ammeter, but while the car is moving, its use to monitor the battery charge is useless.
The only thing that could be thought of with it is to include a generator in the circuit to control the battery recharge current, but this is a too complicated procedure, which, in fact, will not tell you anything useful. If the electrolyte or lead becomes unusable, then the data on the current will not help much, a rapid voltage drop will report this much faster.
Therefore, it is much easier and more convenient to control the voltage on the car battery, on the Internet, for example, a fairly large number of voltmeters are sold cigarette lighters.