Wattmeter
Videos
The wattmeter is an instrument for measuring the electric active power in watts of any given circuit. Electromagnetic wattmeters are used for measurement of utility frequency and audio frequency power
Wattmeter
Early wattmeter on display at the Historic Archive and Museum of Mining in Pachuca, Mexico
Prodigit Model 2000MU (UK version), shown in use and displaying a reading of 10 watts being consumed by the appliance
Itron OpenWay wattmeter with two-way communications for remote reading, in use by DTE Energy
Power factor
Videos
In electrical engineering, the power factor of an AC power system is defined as the ratio of the real power absorbed by the load to the apparent power flowing in the circuit. Real power is the average
Wattmeter
…is proportional to the average instantaneous product of voltage and current, thus measuring active power, P=VI cos φ. Here, cos φ represents the power factor which shows that the power transmitted may be less than the apparent power obtained by multiplying the readings of a voltmeter and ammeter in the same…
1. Reactive power control relay; 2. Network connection points; 3. Slow-blow fuses; 4. Inrush-limiting contactors; 5. Capacitors (single-phase or three-phase units, delta-connection); 6. Transformer (for controls and ventilation fans)
75 MVAr capacitor bank in a 150 kV substation in Belgium
Capacitor bank, consisting of three rectangular capacitors shown in the middle, on a utility pole in San Jose, CA, USA
Power triangle diagram