Division Calibration

United Kingdom

Meters must have been calibrated within the last 12 months to ensure accuracy.

Notes on Division (b)

f1: True power is defined as (volts) × (amps) × (power factor), and is typically reported as watts. Apparent power is defined as (volts) × (amps), and is usually expressed in terms of VA or volt-amps. The power factor for equipment with switching power supplies is always less than 1, so true power is always less than apparent power. Accumulated energy measurements sums power measurements over a period of time and so also need to be based on measurements of true power.
f2: IEC 62301 — Household electrical appliances — Measurement of standby power (2005).