摘要 |
With the heretofore known monitoring systems the parameters or magnitudes to be monitored are converted into electrical signals and transmitted, by means of electrical lines or conductors, to a central station. Because electrical signal transmitters are undesired, particularly in explosion endangered atmospheres or surroundings and, further, since spurious signals can be induced in electrical signal lines, proposals have already been made to utilize monitoring apparatuses working with optical signal conductors. The different embodiments of feelers of the invention, for optical monitoring apparatuses, enable monitoring the continuous change and/or exceeding a predetermined threshold, of electrical, mechanical and thermal parameters or the like. |