[sci.electronics] YMHWQ

grege@gold.gvg.tek.com (Greg Ebert) (01/11/91)

While on the subject of house wiring and kWh meters, my former residence
had 2 legs of a 208 3-phase system for wiring (I verified w/ scope). I
just realized that my kWh meter probably UNDER-read my actual energy
consumption because for a line-to-neutral resistive load, the current
and voltage peaks are 30 degrees out-of-phase with eachother. For 
line-to-line resistive loads, the voltage and current are in-phase, thus
it would read correctly. Anyone concur ? 

robf@mcs213j.cs.umr.edu (Rob Fugina) (01/12/91)

In article <1864@gold.gvg.tek.com> grege@gold.gvg.tek.com (Greg Ebert) writes:
>While on the subject of house wiring and kWh meters, my former residence
>had 2 legs of a 208 3-phase system for wiring (I verified w/ scope). I
>just realized that my kWh meter probably UNDER-read my actual energy
>consumption because for a line-to-neutral resistive load, the current
>and voltage peaks are 30 degrees out-of-phase with eachother. For 
>line-to-line resistive loads, the voltage and current are in-phase, thus
>it would read correctly. Anyone concur ? 

I don't know how kWh meters work, so I can't tell you anything about how
it would measure your power consumption, but I can tell you this.  As far
as line-to-neutral lines in your house are concerned, they would all
work correctly...BUT, anything that you have connected line-to-line, like
an electric furnace, water heater, or stove/oven, they're not getting
the 220v RMS that they're supposed to get...they're only getting
1.73 * 110 instead of 2 * 110.  They're getting 190.5v RMS.

Rob  robf@cs.umr.edu