Siemens SIMATIC - Page 99

Fail-Safe Electronic Modules
8.2 4 /8 F-DI/4 F-DO DC24V/2A PROFIsafe Digital Electronic Module
ET 200pro Distributed I/O System - Fail-Safe Modules
Operating Instructions, 05/2007, A5E00394073-02
99
Use Case 3: Wiring Two Loads in Parallel to Each Digital Output
Avoiding/Managing Cross Circuits:
To protect against cross circuits between P- and M-switches of a fail-safe digital output, we
recommend the following wiring schemes:
2L+ M
DO0
(M0)
DO0
(P0)
DO1
(M1)
DO1
(P1)
DO2
(M2)
DO2
(P2)
DO3
(M3)
DO3
(P3)
4/8 F-DI/4 F-DO
L+ M
K1
K2
K3
K4
M
M
K1
K2
K3
K4
2L+
Figure 8-20 Wiring Diagram for Each of Two Relays Parallel at One F-DO of the 4/8 F-DI/4 F-DO
DC24V/2A PROFIsafe Electronic Module
See also
Block Diagram for the 4/8 F-DI/4 F-DO DC24V/2A PROFIsafe Electronic Module (Page 91)