Ammeter
An instrument used to measure currents is called an ammeter. To measure the current in a wire, you usually have to break or cut the wire and insert the ammeter so that the current to be measured passes through the meter. An ammeter always measures the current passing through it. An ideal ammeter would have zero resistance, so including it in a branch of a circuit would not affect the current in that branch. Real ammeters always have some finite resistance, but it is always desirable for an ammeter to have as little resistance as possible.
Application of Ammeters
Ammeters are used in a variety of applications to measure electric current. Here are some common applications of ammeters:
- Circuit analysis: Ammeters are used to measure current in electrical circuits for diagnostic and analysis purposes. This helps to identify problems or faults in the circuit.
- Power systems: Ammeters are used to measure current in power systems to ensure safe operation and prevent overloading.
- Industrial machinery: Ammeters are used to monitor current in large industrial machines to ensure they are operating within safe limits.
- Automotive: Ammeters are used to measure the charging current of the battery in a vehicle, as well as the current output of the alternator.
- Research and experimentation: Ammeters are used in scientific experiments and research to measure current in electrical circuits.
- Renewable energy: Ammeters are used in renewable energy systems, such as solar panels and wind turbines, to measure the current being generated and monitor system performance.
- Education: Ammeters are commonly used in educational settings to teach students about electrical circuits and the principles of electricity.
Overall, ammeters are essential tools for measuring electric current in a wide range of applications, helping to ensure safe and efficient operation of electrical systems and equipment.
Typical measured currents
Here are six examples of electric currents that can be measured by ammeters, along with their typical values in amperes:
- Household circuits: The current flowing through a typical household circuit in the United States is 15-20 amperes.
- Automotive circuits: The current flowing through the battery or alternator of a car is typically 50-150 amperes.
- Small electronics: The current flowing through the power supply of a small electronic device, such as a cell phone or laptop, is typically 0.1-1 ampere.
- Industrial machinery: The current flowing through large industrial machinery can be several hundred to several thousand amperes.
- Power transmission lines: The current flowing through high-voltage power transmission lines can be tens of thousands of amperes.
- Electric vehicles: The current flowing through the charging circuit of an electric vehicle can be several hundred amperes.
