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The tests were carried out on a carbonfibre reinforced structure with a number of wires with different kind of installation. The peak value of the current impulses ranges from 20 κA up to 200 κA and the comparison shows, that a reasonable linearity exists for carbonfibre reinforced material and that the deviations are always on the save side. The verification of the linearity has been checked then by the so called low-level method. This method uses the transfer function of the whole test arrangement, with the current impulse as the excitation signal and the induced voltage on the wires as the response signal. Also the transfer function shows a good linearity of the system.

The video system with a CCD-Micro-Camera allows the detection of the sparks within the structure. The camera itself with a diameter of 25 mm and a length of 120 mm is protected against the electromagnetic field by a faraday cage. The signal will be transferred by a fibre optical link to the receiver in the measuring cabinet. The signal of the camera will be stored with a digital video recording system, using the data compression procedure M-JPEG. The development of the spark will be recorded by about one or a few pictures, supported by the slow reaction of the camera on the fast brightness change of the real spark. The experiences with the camera system have shown that this is a reliable tool to detect sparks during the test of direct effect of carbon fibre reinforced structures and provide the possibility to detect sparks also within closed components.