beautypg.com

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

Page 153

background image

Span Your Clamp and Ejector Valves

Chapter 9

9-17

If the actual velocity is still not representative of your setpoint, your flow
valve is not linear over the range of your setpoint

If:

And your

Selected Valve is:

Then:

CPS12 was less than CPC12 Direct Acting

Increase FCC48, SCC48, and TCC48 by 5%

Reverse Acting

Decrease FCC48, SCC48, and TCC48 by 5%

CPS12 was more than

CPC12

Direct Acting

Decrease FCC48, SCC48, and TCC48 by 5%

Reverse Acting

Increase FCC48, SCC48, and TCC48 by 5%

Repeat steps 3 through 6 as necessary.

What You Have Accomplished
The valve spanning procedure you just completed has:

defined the range of velocity available during any clamp close profile

informed the QDC module of the signal level needed to drive the

selected clamp velocity valve(s) for any requested open-loop velocity:

% of Signal Level Entered In:

Drives the Selected Valve to Produce:

FCC47, SCC47, TCC47

Velocity (usually 0) in FCC45, SCC45, and TCC45

FCC48, SCC48, TCC48

Velocity in FCC46, SCC46, TCC46

Now, for all open-loop, velocity-controlled clamp close profiles, the QDC
module:

drives the selected clamp velocity valve between the signal limits

imposed by FCC47 and FCC48, or SCC47 and SCC48, or TCC47 and
TCC48

assumes a linear relationship between clamp speed and the signal

outputs