English: An ammeter is a measuring instrument used to quantify the flow of electric current in a circuit. The unit of measurement for current is the ampere, and an ammeter provides a direct reading of the current passing through a conductor. Ammeters are essential tools in electrical testing, circuit analysis, and troubleshooting.

Key features of an ammeter include:

1. Current Sensing: Ammeters are designed to be connected in series with the circuit under investigation. The current to be measured passes through the ammeter, and the device provides a reading proportional to the amount of current flowing through it.

2. Low Resistance: To minimize the impact on the circuit being measured, ammeters typically have a very low resistance. This ensures that the ammeter itself doesn't significantly alter the current flow in the circuit.

3. Scale and Units: The readings on an ammeter are calibrated in amperes (A) or milliamperes (mA) depending on the range of the instrument. Some ammeters have multiple scales or a selector switch to adjust the range for different levels of current.

4. Analog and Digital Types: Ammeters come in both analog and digital forms. Analog ammeters use a needle or pointer on a scale to indicate the current, while digital ammeters provide a numerical readout.

5. Proper Connection: When using an ammeter, it's crucial to connect it correctly in series with the circuit. Connecting an ammeter in parallel can cause a short circuit and damage the ammeter or the circuit.

6. Safety Measures: Ammeters often include safety features such as internal fuses to protect the instrument and the circuit in case of excessive current.

In summary, an ammeter serves as a valuable tool for electricians, engineers, and hobbyists working with electrical circuits. It allows for the precise measurement of current, aiding in the analysis and troubleshooting of electrical systems. Proper usage and understanding of the ammeter's capabilities are essential to ensure accurate readings and prevent damage to both the instrument and the circuit under investigation.

English: An Ammeter