| 摘要 |
<p>The invention relates to a circuit for measuring an electrical quantity at the terminals of a switching element (CC) including a first terminal having an upstream potential (VA) and a second terminal having a downstream potential (VB), characterized in that the measuring circuit includes a device (BF4) for the differential processing of the upstream and downstream potentials powered by a power supply device (BF5) operating only upon the closing of the switching element, wherein a device (BF1) for protecting the upstream potential between said first terminal and a first input of the differential processing device controlled by a device (BF2) for switching the upstream potential powers said first input only when the switching element is closed, and wherein a downstream protection device (BF3) between said second terminal and a second input of the switching element powers said second input.</p> |
