Measuring arrangement having a plurality of measuring points connected to one another by means of a cable

摘要

A measuring cable with spaced measuring stations is laid. The measuring stations each have a sensor whose electrical conductivity depends on an ambient variable such as temperatures light etc., each sensor is provided with a control arrangement which, due to a transmitted signal from a control center, connects its sensor to a constant current source and returns a signal indicative of any voltage change dependent on the variable ambient which signal is measured by the control center. The measuring cable is divided into sections each having a selectable circuit which can be selected individually by the control center. A clock pulse signal is transmitted to all measuring stations but is only active for the cable section which has been selected. In this manner, the cable section can be chosen as desired, the time required for the control center to have access to certain measuring stations is shortened and semiconductor switches can be used because measurements are only made in the steady state.