Paragraph 2 Non-registration testI1

England, Wales and Scotland

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
1. (a)
  1. (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);
  2. (ii)
    the minimum test period shall be computed by the formula—
    $t> \frac{480 x 106 minutes}{k.m. V.Im}$
    where
    t
  3. minimum test period
  4. number of pulses per kWh emitted by the meter
  5. number of elements
  6. declared system voltage
  7. maximum 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—
$t = \frac{126000 minutes}{V \times I \times k \times pf}$
where
t
minimum test period
declared system voltage
total current of all phases
number of pulses emitted per kWh by the meter
power 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.

Paragraph 2 Non-registration testI1

Annotations

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