No person shall connect or permit the connection of any completed or partially completed electrical installation to the electricity supply unless it has been inspected and tested by a registered person and a certificate of compliance for that electrical installation has been issued: Provided that the supplier may on request connect the supply to the electrical installation for the purpose of testing and the completion of the certificate of compliance by a registered person: Provided further that this subregulation shall not apply in a case where the electricity was disconnected for the non-payment of the electricity account or where there has been a change of tenant but not of ownership.