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VAR
>Richard Hull, TCBOR
>AC watts are volt-amps in a purely resistive AC circuit (like frying a
>human being.) But not in Tesla coil power circuitry. the correct term
>is VAR, volt-amps-reactive.
>This tells the listener that a simple current and voltage measurement was
>taken in an AC circuit with known reactance present, but without a phase angle,
>tells little more.
Uhmmmmm. That may be the way the term VAR is used in the Tesla Field.
Electrical engineers asign it a more specific meaning. VAR is
DEFINED AS the '90 degree' value. That is if a cap or inductor
(neglecting resistance) is thron on line it draws ONLY VARs.
(in fact, systemc ontrol boards have 'VAR meters' to aid in setting
up PF correction caps. In fact PF correction banks are commonly rated
as '<mumble> VAR' banks.
So with a complex load, there will be:
WATTS == in phase power.
VA == Volts times amps == greater than WATTs
VAR == VOLTS times AMPS at 90 degrees (imaginary).
WATTS being defined as tue power and VAR as 'imaginary' power, the
vector sum should match VA.
('imaginary' has a specific meaning in electrical engineering. I
would guess most of the list members are familiar with this, but a
few may not be...)
regards
dwp