10.—(1) This paragraph applies to meters used for ascertaining the quantity of electricity supplied to any premises.
(2) The register of a meter to which this paragraph applies shall be admissible in any proceedings as evidence of the quantity of electricity supplied through it.
(3) Where electricity has been supplied for any period through such a meter which is of an approved pattern or construction and is installed in an approved manner, the register of the meter shall be presumed to have been registering for that period—
(a)within the prescribed margins of error; and
(b)in the case of a meter used in connection with an exempt supply, within any agreed margins of error,
unless the contrary is proved.
(4) Where a meter to which this paragraph applies has been operating for any period—
(a)within the prescribed margins of error; and
(b)in the case of a meter used in connection with an exempt supply, within any agreed margins of error,
the meter shall be conclusively presumed to have been correctly registering for that period the quantity of electricity supplied through it.
(5) The report of a meter examiner on any question relating to such a meter shall be admissible in evidence in any proceedings in which that question is raised; and any conclusions in the report as to the accuracy of the meter when it was tested shall be presumed to be correct unless the contrary is proved.