Wiring of Input Devices/Sensors

Overview

The following graphic presents dual-channel wiring of safety-related input devices/sensors to the safety module eSM with and without cross-circuit detection:

Cross Circuit Detection

The outputs CCM24V_OUT_A and CCM24V_OUT_B of the safety module eSM provide 24 Vdc supply voltage with cross circuit detection for input devices/sensors with relay output contacts. In the case of dual-channel wiring and supply of the input devices/sensors via CCM24V_OUT_A and CCM24V_OUT_B, cross circuits between channels and short circuits to other conductors can be detected.

The maximum safety-related data specified for the safety module eSM (SIL, PL) are reached with and without cross circuit detection.

Cross circuit detection:

1	Cross circuit detection detects cross circuits between signals whose names have the suffix "_A" and signals of the same name with the suffix "_B" supplied via the 24 Vdc power supply, for example, between ESTOP_A and ESTOP_B.
2	Cross circuits between signals with different name, but with the same suffix are not detected, for example, cross circuits between ESTOP_A and GUARD_A