NOVELTY - The plant contains an electrolyser (1) for water decomposition, located within a housing formed by a body (27) and external lids, water supply line, electrolyte, and electrolysis products outlet line. The plant also has units for pumping the electrolyser products, an external electrolyte solution circulation circuit with outlet and inlet pipes, electrolyser rotation drive, a heat exchanger (8) and a unit for water flow rate regulation (25). The electrolyser is provided with a separator located on the electrolysis outlet line and inner and outer electrodes. The inner electrode envelopes the electrolyser shaft (30) and the outer electrode is formed by electrolyser body. The electrolyser drive is screened and consists of inner (10) and outer (11) units separated by non-magnetic screen (12) connected to one of the protecting housing lids. The internal zone of the non-magnetic screen and the outer body form a sealed space. The water flow rate regulation unit is located on the outlet pipe and comprises a device (22) for measuring electrolyte solution density and a magnetic field source with poles forming a radial gap that contains the electrolyte solution circulation circuit inlet pipe. The electrolyser is provided with radial openings    USE - For production of hydrogen and oxygen for technological purposes and can be used in automobile construction industry.    ADVANTAGE - The plant construction on the whole and its individual parts is simplified, liquid and gas containers are securely sealed and water supply is automatically regulated.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for    (A) hydrogen and oxygen production plant operation method    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the hydrogen and oxygen production plant    Electrolyser (1)    Heat exchanger (8)    Eelectrolyser drive inner and outer units (10,11)    Non-magnetic screen (12)    Electrolyte density measuring device (22)    Water flow rate regulator (25)    Electrolyser housing (27)