摘要 |
<p>In the case of a protective device in a controller which contains at least one processor and is connected to a sensor via a sensor ground line and at least one further line, the invention provides that a ground in the controller is connected to the sensor ground line via a semiconductor switch which disconnects or connects the ground and the sensor ground line as a function of whether the current through the sensor ground line and/or the voltage between ground and the sensor ground line are/is in each case greater or less than a predetermined value, and that the voltage which is applied to ground or is applied to the sensor ground line can be applied to an internal ground, which is used for measurement purposes, controlled by the processor with the aid of two further semiconductor switches.</p> |