Rockwell Automation 1785-LTx,D17856.2.1 Classic PLC-5 Programmable Controllers Users Manual - Manual (Page 152)

Design Worksheets
Appendix B
B-2
Prepare a Functional Specification
For more information on: See:
Functional specifications Classic 1785 PLCĆ5 Programmable Controllers User Manual, publication 1785Ć6.2.1, Chapter 1:
Designing Systems
Preparing Your Functional Specification
1. Divide your manufacturing process into functional areas.
2. Make a copy of the reverse side of this worksheet for each functional area.
3. For each functional area, document the following:
Information to Document Example(s)
Inputs Actions and signals, ranges, quantities, timing, tolerance, units of measure, validation
requirements, possible errors, and error responses
Outputs Quantities, units of measure, timing, tolerances, ranges, validation methods, method
or reporting invalid outputs, locations, methods of data output, physical requirements
Performance requirements Accuracy; maximum and minimum transition times; interface timing; operator
response timing; adherence to standards such as IEEE, ANSI
Interfaces Operator, software, hardware
Failure modes and recovery methods Fault routines
Security requirements Operator access, alarming, etc.
Maintenance requirements Documentation, spare parts, accessibility
4. Use the information on these worksheets to develop a complete functional specification.