Vigilant User Manual
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In case the sensor has a NPN output type, the normal connection between the sensor and the auxiliary
inputs would be something like this:
In case the sensor has a PNP output, the connection would look like this:
9.5.2.
4-20 mA Signal
Dynamic inputs can be configured to measure 4-20 mA current loop signals. This kind of current loop
is an industry-standard used in many applications. They have the advantages of simplicity and noise
immunity and have a large international user and equipment supplier base.
In order to read this type of signals from the main inputs a resistance must be connected on the
terminals in order to convert the current signal into a voltage. The following graphs show the wiring
required for a passive 4-20 mA loop sensor:
