Siemens SIMATIC S5-95F - Using the Failsafe, Onboard Digital Inputs

S5-95F Installing and Connecting the Basic System
4.2.1 Using the Failsafe, Onboard Digital Inputs
The onboard digital inputs are located on the right-hand side of the 40-pin connector. They are
galvanically isolated from the internal reference potential of the basic unit.
How to Connect the Onboard DI
Connect the 24 V DC load voltage (L+ potential to terminal 1, L- potential to terminal 20).
Connect the sensor to the digital output selected. You can connect either single-channel or two-
channel failsfafe sensors.
Connection of Single-Channel, Failsafe Sensors (Type B)
Figure 4-8. Connection of a Single-Channel, Failsafe Sensor
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Single-channel,
failsafe sensor
EWA 4NEB 812 6210-02 4-9