The EL1052 digital input terminal acquires signals from NAMUR sensors according to IEC 60947-5-6. The sensors are supplied with a voltage of 8.2 V and return a diagnosable current signal. In this way, a wire breakage or short-circuit can be detected in addition to the switching state. The LEDs indicate signal or any error states, channel by channel.

The most widely used NAMUR sensors are proximity switches, which are used, for example, as limit switches in control valves. In principle, both normally open (NO) and normally closed (NC) contacts can be operated with the EL105x. Any inversion of the status bits must be taken into account.

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