Allen-Bradley 1757-FFLD2, User Manual

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Rockwell Automation Publication 1757-UM012A-EN-P - July 2011 99
Create an RSLogix 5000 Software Project Chapter 5
EXAMPLE
In the following scenario, Disable keying prevents I/O communication :
The module configuration is for a 1756-IA16 digital input module. The physical module is a 1756-IF16 analog input
module. In this case,
communication is prevented because the analog module rejects the data formats that the
digital module configuration requests .
EXAMPLE
In the following scenario, Disable keying allows I/O communication :
The module configuration is for a 1756-IA16 digital input module. The physical module is a 1756-IB16 digital input
module. In this case, communication is allowed because the two digital modules share common data formats.
Module Configuration
Vendor = Allen-Bradley
Product Type = Digital Input
Module
Catalog Number = 1756-IA16
Major Revision = 3
Minor Revision = 1
Physical Module
Vendor = Allen-Bradley
Product Type = Analog Input
Module
Catalog Number = 1756-IF16
Major Revision = 3
Minor Revision = 2
Communication is prevented.
Module Configuration
Vendor = Allen-Bradley
Product Type = Digital Input
Module
Catalog Number = 1756-IA16
Major Revision = 2
Minor Revision = 1
Physical Module
Vendor = Allen-Bradley
Product Type = Digital Input
Module
Catalog Number = 1756-IB16
Major Revision = 3
Minor Revision = 2
Communication is allowed.
IMPORTANT
Changing electronic keying selections online may cause the I/O
communication connection to the module to be disrupted and may
result in a loss of data.