Rockwell Automation 1771-QDC, D17716.5.87(Passport) CLAMP AND EJECT MODE - Manual (Page 173)

Span Your Clamp and Ejector Valves
Chapter 9
9-37
What You Have Accomplished
The valve spanning procedure you just completed has:
defined the range of velocity available during any ejector profile
informed the QDC module of the signal level needed to drive the
selected ejector velocity valve(s) for any requested open-loop velocity:
% of Signal Level Entered In: Drives the Selected Valve to Produce:
EAC47 and ERC47 Velocity (usually 0) in EAC45 and ERC45
EAC48 and ERC48 Pressure in EAC46 and ERC46
Now, for all open-loop, velocity-controlled ejector profiles, the QDC
module:
drives the selected ejector velocity valve between the signal limits
imposed by EAC47 and EAC48, or ERC47 and ERC48
assumes a linear relationship between ejector speed and the signal
outputs