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Rockwell Automation Publication 1756-UM013B-EN-P - October 2019
Chapter 1
Digital Safety I/O Module Operation in a Control System
Overview
GuardLogix® controllers use 1756-IB16S and 1756-OBV8S modules to control
devices in a control system.
ControlLogix modules mount in a ControlLogix chassis, and require a
removable terminal block (RTB) to connect all field-side wiring.
Table 1 - 1756 ControlLogix® Digital Safety I/O Modules
Module Type
Cat. No.
Description
Safety
(1)
(1) You can use the safety modules in applications that are rated up to, and including, SIL CL3, PLe, Cat. 4 as defined in IEC 61508,
IEC 61511, IEC 62061, and ISO 13849-1.
1756-IB16S
18…32V DC 16-point sinking safety input module
1756-OBV8S
18…32V DC 8-point, safety output module that can be used as:
• Bipolar output module
• Sourcing output module
ATTENTION:
The 1756-IB16S and 1756-OBV8S modules are compatible with a
1756 ControlLogix Chassis, Series C. Do not install the 1756-IB16S and
1756-OBV8S modules in a 1756 ControlLogix Chassis, Series B.
ATTENTION:
Due to the higher internal power dissipation of the 1756-OBV8S
module, do not install the 1756-OBV8S module next to any controller or
communication module.
IMPORTANT
A ControlLogix system with 1756-IB16S and 1756-OBV8S safety I/O modules
has been agency certified using only the ControlLogix RTB catalog numbers
1756-TBCHS, 1756-TBNHS, 1756-TBSHS, and 1756-TBS6HS.
Any application that requires agency certification of the ControlLogix system
using other wiring termination methods can require application-specific
approval by the certifying agency.
ATTENTION:
To comply with the CE Low Voltage Directive (LVD), this
equipment, and all connected I/O, must be powered from a safety extra low
voltage (SELV) or protected extra low voltage (PELV) compliant source.
For UL-compliant applications, the 1756-IB16S and 1756-OBV8S modules, and all
connected IO, must be powered from a SELV or PELV-compliant power source that is
rated 150VA maximum.
IMPORTANT
All other I/O modules in the same chassis must use an SELV/PELV power supply.
Summary of Contents for 1756 Series
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