User manual

Publication 1756-RM093F-EN-P - January 2010 85
Safety Add-On Instructions Appendix B
Create Add-On Instruction Test Project
You need to create a unique test project, specifically for creating and
testing the safety Add-On Instruction. This must be a separate and
dedicated project to minimize any unexpected influences.
Follow the guidelines for projects described in Create the Project
on
page 56.
Create a Safety Add-On Instruction
For guidance in creating Add-On Instructions, refer to the Logix5000
Controllers Add-On Instruction Programming Manual, publication
1756-PM010
.
Generate Instruction Signature
The instruction signature lets you quickly determine if the instruction
has been modified. Each Add-On Instruction has the ability to have its
own signature. The instruction signature is required when an Add-On
Instruction is used in safety-related functions, and may be required for
regulated industries. Use it when your application calls for a higher
level of integrity.
The instruction signature consists of an ID number and timestamp that
identifies the contents of the Add-On Instruction at a given point in
time.
Once generated, the instruction signature seals the Add-On
Instruction, preventing it from being edited while the signature is in
place. This includes rung comments, tag descriptions, and any
instruction documentation that was created. When the instruction is
sealed, you can perform only these actions:
• Copy the instruction signature
• Create or copy a signature history entry
• Create instances of the Add-On Instruction
• Download the instruction
• Remove the instruction signature
• Print reports