Allen-Bradley ClutchBrake PLC-5 Series - Feedback Timing Diagrams; Timing Diagrams for Control System Feedback

Appendix B
Publication 65566.5.1 - October 1996
Feedback Timing Diagrams
We define the controller’s feedback response time for these signals:
• triac and valve-stem feedback
(where valve-stem feedback pertains to main, auxiliary,
and/or micro-inch valves with external fault detection)
• motion detector feedback
When PLC-5/x6 processors command triacs ON or OFF, they check
that feedback signals (triac, valve stem, and motion detector) have
turned ON or OFF in the order shown and within the times shown.
This feedback
signal:
Has a turnon time measured
from offtoon transition of:
and a turnoff time measured
from ontooff transition of:
Triac [ 1 ] triac command [ 4 ] triac command
Valvestem [ 2 ] triac feedback
Motion Detector Turns ON before upstroke
(Before BCAMs turn OFF)
Triac Command
ON
OFF
Triac Feedback
ON
OFF
01 sec
Valve Stem Feedback
OFF
01 sec
[1]
[4]
03 sec
[4]
Motion Detector must turn ON before upstroke
(before Brakemontor cams (BCAMs) turn OFF)
Offtoon transition Ontooff transition
position dependent Time dependent
ON
OFF
01 sec
01 sec
[1]
[4]
If and when a PLC-5/x6 processor detects that a triac or feedback
signal has not turned ON or OFF within the times shown, it trips
seal relay output to remove power from the wiring arm of
1771-OD16 output module.
If your main valves have external fault-detection with valve-stem
switches and you configured for valve-stem feedback, you have two
options for the other solenoid valve inputs:
• they also must have external valve-stem switches and feedback, or
• if they have internal fault detection, you must simulate external
valve-stem feedback for them (See wiring drawings 8 and 9)
Timing Diagrams for
Control System Feedback