The invention relates to a monitoring system for monitoring a third-party device, in particular a medical device, wherein the third-party device has a signal device for displaying the device status and/or relevant device properties and the monitoring device (2) is associated with the third-party device. Based upon this prior art, in the context of the invention monitoring of the third-party device should be possible and should also operate when the actual status indication of the monitored third-party device is defective. In this connection within the context of the monitoring system according to the invention it is not the status indication of the devices but rather a current proportional to the device status within the monitored third-party device is inductively sensed, evaluated and optionally an emergency signal is detected as a function of the result of the evaluation. The invention also relates to monitoring defibrillators.
