Supervision system for electromagnetically protected items in several supervision zones

摘要

The invention relates to a system for supervising electromagnetically protected items in n supervision zones (n>/=2). Each of the n supervision zones is defined by two transmitting/receiving devices which are arranged on both sides of the zone. Each transmitting device has at least one transmitting reel and each receiving device has m receiving reels (m>/=1). The invention seeks to provide an inexpensive system for supervising electromagnetically protected items. To this end, a switching device (10) is fitted which reduces the outputs of the (2.n) receiving devices (4) to n outputs.