AC-DC Current Shunts vs. Current Transformers
Although all Valhalla wattmeters are compatible with general purpose current transformers, there are distinct accuracy and bandwidth advantages to using a current shunt when making a power measurement. Current shunts generally provide greater accuracy over a broader...
Watts Converters
For Distorted Waveshapes of All Types The success of the Valhalla 2100 series wattmeter design is centered around a four-quadrant multiplier. The significance of the four quadrant theory is to provide a proper computation for watts under any phase relation between...
Power Measurements in Inductive Circuits
The AC power drawn from the source (e.g. line - 120VAC @ 60Hz 220VAC @ 50Hz) is the integral over one cycle of the instantaneous watts values. As shown in figure C, during a portion of each cycle power is used by the inductive device (e.g. electric motor), while...
RMS, Average, and Peak Amplitude Measurements
When describing the amplitudes of electronic devices, terms such as "volts RMS" or "amperes RMS" are used. The RMS (root mean square) of a sine wave produces the same "heating effect" as an equivalent DC voltage level. (i.e. 5 VAC RMS = 5 VDC). Since a given AC...