NOVELTY - Control and adjustment method for switching position of switch connection between electric outputs of fuel cell in mobile system, and mains network insulated in mobile system    USE - For controlling switching position of switch connection between electric outputs of fuel cell arranged in a mobile system.    ADVANTAGE - Safety measures are provided to reduce any risk of harm to persons, or damage to part of the mobile system. Monitoring is carried out by sensors and during operation, and any uncontrolled of hydrogen from the fuel cell is detected. The high and low voltage mains are insulated from each other.    DETAILED DESCRIPTION - The additional mains supply has a smaller voltage than the mains connectable at the fuel cell (1) as well as a storage battery. The method is carried out using sensors arranged in or at the mobile system which signal the system conditions. The supply of the electric insulated mains with power must be interrupted or excluded on safety grounds. A control and evaluation unit is supplied from the further mains, and the sensors. The switch connection at the outputs of the fuel cell is formed by at least one isolating switch. The power for the closing of the working contacts with the starting of the fuel cell, after the reaching of the operating readiness of the fuel cell, is released by the control and evaluation unit from the further mains. The detection of a signal from at least one sensor, is related to an unpermitted closed position of the working contacts, on safety grounds. The power supply from the control and evaluation unit to the isolating switch is blocked on interruption.    DESCRIPTION OF DRAWING(S) - The figure shows a block diagram of an arrangement for controlling switching positions of a switch connection the electric outputs of fuel cell arranged in vehicle and electric insulated mains arranged in vehicle.    Fuel cell (1)    Electric outputs of cell (2,3)    Working contacts (4,5)    Traction motor (8)    Contactors or relays (9,10)    Economizers (11,12)    Processor (30)    Current sensor (39)    A-D converter (40)    Voltage divider (46)