Underground supply network with management devices

摘要

The supply network has a number of underground supply lines (1) provided with node points (2), with accessible node points identified via information plates (3) positioned above the ground, for facilitating maintenance or testing. Selected information plates can each be provided with a transponder (5) for supplying testing and maintenance data to a memory (9) within a hand-held interrogation device (6) having a display (7) for read-out of the received data.