Power Applications: Measurement Techniques
One often needs to make power measurements when dealing with energy distribution, power supplies, motors and motor controls. Power is usually measured with a wattmeter or, in some cases, by temperature sensors which indicate energy loss. Temperature sensors are hard to calibrate. Wattmeters are set up to deal with sinusoidal signals, therefore lacking the frequency response needed for dealing with noisy signals from switching power supplies. A digital oscilloscope, or transient analyzer, can enable you to capture current and voltage waveforms, and calculate power with high precision and confidence.