Hello Jon DeLee,
There are three kinds of power: Active power(P), Apparent pow er(S) ,Reactive power(Q)
Our meter only monitor Active power(P)
Apparent power: S= U*I
Active power : P=U*I*cosφ (cosφ is power factor)
Different load have different power factor, so active power is not always equal to U*I.
For example, the cosφ for pure resistive load is near 1, so the Active power can be closed to U*I ;
The cosφ for inductive load and capacitive load is between 0-1, so the Active pow er is less than U*I.
Our meter also read power factor. You can check that.
And the reset button is under the lower right of meter, there is a hole, you can press it with wooden stick or other thing, just hold 5 seconds, then kwh will be reset.
Best regards,
DROK
Drok.
