Which symbol represents a wattmeter in circuit diagrams?

Which symbol represents a wattmeter in circuit diagrams?

• A. Ammeter symbol
• B. Wattmeter symbol
• C. Voltmeter symbol
• D. Ohmmeter symbol

Answer: (B)

Power is what a wattmeter measures, so the symbol used for that instrument identifies a wattmeter in circuit diagrams. In schematics, ammeters show current and are placed in series, voltmeters show voltage and are placed in parallel, and ohmmeters measure resistance. A wattmeter, by contrast, is designed to measure electrical power by combining the voltage and current in the circuit, and its symbol is the one labeled with a W (the wattmeter symbol). That’s why this symbol is the correct choice.

Power is what a wattmeter measures, so the symbol used for that instrument identifies a wattmeter in circuit diagrams. In schematics, ammeters show current and are placed in series, voltmeters show voltage and are placed in parallel, and ohmmeters measure resistance. A wattmeter, by contrast, is designed to measure electrical power by combining the voltage and current in the circuit, and its symbol is the one labeled with a W (the wattmeter symbol). That’s why this symbol is the correct choice.