
Rockwell Automation Publication 1756-UM013B-EN-P - October 2019
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Digital Safety I/O Module Operation in a Control System
Chapter 1
Connections with 1756 ControlLogix Digital Safety I/O Modules
During module configuration, you must define the module. Among the Module
Definition parameters with 1756 ControlLogix digital I/O modules, you must
choose a connection type for the module. A connection is a real-time data
transfer link between the owner-controller and the module that occupies the slot
that the configuration references.
When you download module configuration to a controller, the controller
attempts to establish a connection to each module in the configuration.
Because part of module configuration includes a slot number in the local or
remote system, the owner-controller checks for the presence of a module there. If
a module is detected, the owner-controller sends the configuration. One of the
following occurs:
• If the configuration is appropriate to the module detected, a connection is
made and operation begins.
• If the configuration is not appropriate to the module detected, the data is
rejected and the Logix Designer application indicates that an error
occurred.
The configuration can be inappropriate for many reasons. For example, a
mismatch in electronic keying that prevents normal operation.
The owner-controller monitors its connection with a module. Any break in the
connection, for example, the loss of power to the system, causes a fault. The Logix
Designer application monitors the fault status tags to indicate when a fault occurs
on a module.
During module configuration, you must define the module. Among the Module
Definition parameters with 1756 ControlLogix digital safety I/O modules, you
must choose how module is configured.
The choice depends on whether the project is downloaded to the controller that
owns the module configuration, that is, the owner-controller, or to a controller
that is listening to input modules in a project.
A real-time data transfer link is established between the controller and the
module that occupies the slot that the configuration references.
When you download module configuration to a controller, the controller
attempts to establish a connection to each module in the configuration.
Summary of Contents for 1756 Series
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