21. (1) A licensee shall not be entitled to prescribe any special form of appliance for utilising energy supplied by him, or, save as provided by section 23, sub-section (2), or by section 26, sub-section (7), in anyway to control or interfere with the use of such energy:Provided that no person may adopt any form of appliance, or use the energy supplied to him, so as unduly or improperly to interfere with the supply by the licensee of energy to any other person.(2) Subject to the provisions of sub-section (1), a licensee may, with the previous sanction of the Government, given after consulting the local authority, where the licensee is not the local authority, make conditions not inconsistent with this Act or with his license or with any rules made under this Act, to regulate his relations with persons who are or intend to become consumers, and may, with the like sanction given after the like consultation, add to or alter or amend any such conditions; and any conditions made by a licensee without such sanction shall be null and void: ¹[* * *](3) The Government may, after the like consultation, cancel any condition or part of a condition previously sanctioned under sub-section (2) after giving to the licensee not less than one month's notice in writing of its intention so to do.(4) Where any difference or dispute arises as to whether a licensee has prescribed any appliance or controlled or interfered with the use of energy in contravention of sub-section (1), the matter shall be either referred to an Electric Inspector and decided by him or, if the licensee or consumer so desires, determined by arbitration.