
Rockwell Automation Publication 1756-UM013B-EN-P - October 2019
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Application and Wiring Examples for Safety Modules
Appendix C
1756-OBV8S Module
Wiring Diagrams
You can use the 1756-OBV8S module in Bipolar mode or Sourcing mode.
Bipolar Mode
When the module is wired as shown, it is suitable for applications that are rated
up to, and including,
Category 2
and
PLd
as defined in ISO 13849-1.
To achieve that suitability rating, you may have to perform diagnostic testing and
monitoring of the safety function. One diagnostic test method is to configure the
safety output channel for Safety Pulse Test to test the circuit for short circuits to
24V DC.
IMPORTANT
• The 24V (DC+ and DC-) power connections are used to supply field-side power to the
module.
• All terminals with the same name are connected together on the module. For example, DC+
can be connected to either terminal marked DC +.
• Do not physically connect more than two wires to one RTB terminal.
DC(+)
DC(-)
DC(+)
DC(-)
OUT0-P
OUT1-P
OUT4-P
OUT3-P
OUT2-P
OUT5-P
OUT6-P
OUT7-P
OUT0-M
OUT1-M
OUT2-M
OUT3-M
OUT4-M
OUT5-M
OUT6-M
OUT7-M
+ -
K
M
24V DC
SELV/PELV-listed power
supply
Channel Connections
This wiring example shows connections to Safety Output 0. You
are not limited to using channel 0 in this mode. You can use all
channels as determined by your application.
We
strongly recommend
that, if you have a direct connection
between the safety output module and an input module and those
modules are powered by separate power supplies, you connect
module DC- and actuator DC- together. This practice helps to
eliminate grounding float from disrupting diagnostics.
Summary of Contents for 1756 Series
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