(1) ] Where any person neglects to pay any charge for energy or any 2[ sum, other than a charge for energy,] due from him to a licensee in respect of the supply of energy to him, the licensee may, after giving not less than seven clear days' notice in writing to such person and without prejudice to his right to recover such charge or other sum by suit, cut off the supply and for that purpose cut or disconnect any electric supply- line or other works, being the property of the licensee, through which energy may be supplied, and may discontinue the supply until such charge or other sum, together with any expenses incurred by him in cutting off and reconnecting the supply, are paid, but no longer.