Rockwell Automation Publication 1756-UM013B-EN-P - October 2019
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1756-OBV8S Output Module Features
Chapter 4
Forcing
Use a force to override data that your logic either uses or produces.
• Test and debug your logic.
• Temporarily maintain normal system operations when an input device
has failed.
Use forces only as a temporary measure. They are not intended to be a permanent
part of your application.
Make sure that you understand this before you use forces.
Enable Forces
For a force to take effect, you enable forces. You can only enable and disable forces
at the controller level.
• You can enable I/O forces and SFC forces separately or simultaneously.
• You cannot enable or disable forces for a specific module, tag collection, or
tag element.
IMPORTANT
When a safety signature exists, forcing safety I/O is not permitted in the safety
portion of the application.
ATTENTION:
Forcing can cause unexpected machine motion that could
injure personnel. Before you use a force, determine how the force affects
your machine or process and keep personnel away from the machine area.
• Enabling I/O or SFC forces causes your machine or process to go to another
state or phase.
• Removing forces can still leave forces in the enabled state.
• If forces are enabled and you install a force, the new force immediately
takes effect.
Summary of Contents for 1756 Series
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