Rockwell Automation Logix5000 Controllers Add-on Instructions Programming Manual - Manual (Page 62)

Chapter 2 Defining Add-On Instructions
1. On the Signature tab on the Add-On Instruction Definition Editor, click
Add to History.
2. In the Create History Entry description box, type up to 512 characters
long, for the entry.
3. Click OK.
Tip: To facilitate record-keeping, you can copy the entire signature history to the clipboard by selecting all the
rows in the signature history and choosing Copy from the Edit menu. The data is copied in tab separated
value (TSV) format.
To delete the signature history, click Clear Signature History. You must be
offline to delete the Signature History.
Generating a Safety Instruction Signature
When a sealed safety Add-On Instruction is downloaded for the first time, a SIL 3
safety instruction signature is automatically generated. Once created, the safety
instruction signature is compared at every download.
If Logix Designer application detects an invalid safety instruction signature value,
it generates a new safety instruction signature value in the offline project and
displays a warning indicating that the safety instruction signature was changed.
The safety instruction signature is deleted if the instruction signature is removed.
Important: After testing the safety Add-On Instruction and verifying its functionality, you must record the
instruction signature, the safety instruction signature and the timestamp value. Recording these
values will help you determine if the instruction functionality has changed.
Refer to the
GuardLogix Controller Systems Safety Reference Manual , publication 1756-RM093 ,
for details on safety application requirements.
Viewing and printing the instruction signature
When the instruction signature has been generated, Logix Designer application
displays the instruction with the blue seal icon in the Controller Organizer, on
the Add-On Instruction title bar, and in the Logic Editor.
62 Rockwell Automation Publication 1756-PM010F-EN-P - October 2014