Re: Wattmeter

Recently, someone asked about the feasibility of using a watt-hour meter as
a means of measuring wattage, but noone responded.  Suppose one uses a
watt-hour meter of the type that is commonly used to bill us for our home
power useage.  If one monitors just the TC HV transformer (pig, nst, pt)
for a precise time such as 60 or 100 seconds, will one get a fairly
accurate indication of average power?  Does mechanical inertia, etc. take
care of the erratic waveforms it must handle?  I like the almost
indestructable character of watt-hour meters--they seem to live forever.



> An electronic
> Wattmeter must take scaled samples of the voltage and the current in the
> load, multiply them, average the result, and take the square root.
> Any other approach will not work correctly with arbitrary waveforms.
> Antonio Carlos M. de Queiroz