# The Meters (Certification) Regulations 1998, Paragraph 2: Non-registration test

Extent: E+W+S

Induction meters
(1) Induction meters shall be tested to ensure that when the current circuits are open and a voltage of 110 per cent. of the declared system voltage is applied to the voltage circuits, rotors cease to rotate before completing one revolution.
Static meters
(2) Static meters shall be tested for non-registration by one of the following methods—
Method 1
(a)(i)When subjected to the test conditions specified in paragraph 2(1), the meter shall not emit more than one output pulse over the minimum test period determined in paragraph (ii);
(ii)the minimum test period shall be computed by the formula—
t>480x106 minutesk.m. V.Im where
tminimum test period
Knumber of pulses per kWh emitted by the meter
mnumber of elements
Vdeclared system voltage
Immaximum rated current.
For transformer-operated meters, k and Im must either both relate to primary values or both relate to secondary values.
Method 2
(b)When static meters are fitted with inhibiting circuits, they may be tested for non-registration with a current which is less than the threshold current in respect of a meter of that type and at a voltage of 100 per cent. of the declared system voltage of the meters under test. Meters shall not emit more than one output pulse over the minimum test period determined as follows—
t=126000 minutesV×I×k×pf where
tminimum test period
Vdeclared system voltage
Itotal current of all phases
knumber of pulses emitted per kWh by the meter
pfpower factor.
Method 3
(c)The period calculated for method 1 or method 2 may be halved if the meters under test do not emit any output pulses during the period of the test.

---
Source: https://www.legislation.gov.uk/uksi/1998/1566/schedule/1/paragraph/2 (the official version)
Page: https://openlegislation.uk/meters-certification-regulations-1998/schedule-1/paragraph-2
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.