RE: Watt meters

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

Original poster: "John H. Couture" <couturejh-at-mgte-dot-com> 


Adam -

The electric energy meter on the side of your house can also be called a
watthour meter. It measures  volts x amps x time in kilowatt hours (KWHs).
You can calculate KW by dividing the watt hours by the time. The electric
company would not know or assume an inductive load for any customer. The
customer would not accept the electric company charging him based on
assumptions. However, if you have a large electric load they may want to
bill you additional charges for the reactive (inductive) portion of your
load. This is normally in the form of a demand meter. With this information
you could calculate the power factor. For residences the charge per KWH
includes an extra amount for the average (assumed?) house inductive load.

The electric utility bill can be a very complex bill today because of the
many types of electric loads and the rising cost of electricity. The biggest
problems are harmonics and jumbled waveshapes caused by electronic motor
controls and the millions of computers.

John Couture

---------------------------------


-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Monday, March 15, 2004 10:08 AM
To: tesla-at-pupman-dot-com
Subject: Re: Watt meters


Original poster: Yurtle Turtle <yurtle_t-at-yahoo-dot-com>

I have two residential electric (energy) meters. These
are the ones that are used to calculate my power bill.
I assume these can be used with a stop watch to
calculate KW? How do they calculate PF? Do they assume
a certain inductive load? For inductive load, a normal
house normally only has HVAC, Refrigerator/Freezer,
and Washer/Dryer. Garage door openers, etc. are
probably insignificant.

Adam

--- Tesla list <tesla-at-pupman-dot-com> wrote:
  > Original poster: "Lau, Gary" <gary.lau-at-hp-dot-com>
  >
  > I found a Weston analog Watt meter (0-2 & 0-4kW) at
  > a ham fest some time
  > ago and have yet to try it.  There are a pair of
  > terminals for load
  > voltage and another pair for load current sensing.
  > My question is -
  > will this read true watts with a reactive (i.e.
  > Tesla coil) load?
  >
  > Thanks, Gary Lau
  > MA, USA
  >
  >