Re: Watt meters

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: dave pierson <davep-at-quik-dot-com> 

 >The original usage meters (in DC Edison days) were electrolytic cells with

>silver electrodes.  The silver would plate from one to the other.
>periodically, they'd weigh the two plates, then interchange them.  This
>would be a coulomb sensor, and reactive power would transfer silver.

    There are also DC motor analogs to the AC 'induction' meters
    we have been discussing.


>I suspect (without actually doing any hardcore research) that the present
>electrodynamic meters have been around since 1900 or earlier, pretty much as
>soon as AC distribution came into being.  The idea of power factor and
>reactive power was known and understood very early on.

    Just so.
    I have old texts and without cracking them, 19-- matches what I
    recall.

    The '1 Amp inductor' woiuld/should show as drawing 'some'
    'real power' unless _perfect_.
    8)>>

    Stray losses in core and in wire resistance,,,,

    best
     dwp