Abstract: The invention relates to an electrical system comprising: —terminals (V+, V?) capable of being connected to an installed electrical power source (4) capable of delivering an electrical voltage between said terminals; —a circuit for detecting an electrical insulation fault between the electrical power source and a housing (14) forming a floating electrical ground. The detection circuit comprises: •a controllable voltage generator (40) capable of polarizing the housing and the single first terminal at different potentials; •a current measurement device (44) measuring current entering on said first terminal and leaving at a point of the source; •a control unit (46) capable of calculating a value of at least one insulation resistance from said at least one measured current value.

Abstract: The invention relates to an electrical system comprising: —terminals (V+, V?) capable of being connected to an installed electrical power source (4) capable of delivering an electrical voltage between said terminals; —a circuit for detecting an electrical insulation fault between the electrical power source and a housing (14) forming a floating electrical ground. The detection circuit comprises: •a controllable voltage generator (40) capable of polarising the housing and the single first terminal at different potentials; •a current measurement device (44) measuring current entering on said first terminal and leaving at a point of the source; •a control unit (46) capable of calculating a value of at least one insulation resistance from said at least one measured current value.