Rockwell Automation 1761-HHP-B30 MicroLogix 1000 with Hand-Held Programmer (HHP) - Manual (Page 452)

Appendix E
Application Example Programs
E–9
Rung 6:0
This section of ladder logic controls the up/down motion of the drill for
the book drilling machine. When the conveyor positions the book under the
drill, the DRILL SEQUENCE START bit is set. This rung uses that bit to
begin the drilling operation. Because the bit is set for the entire
drilling operation, the OSR is required to be able to turn off the forward
signal so the drill can retract.
| Drill |Drill Subr| Drill |
| Sequence | OSR | Forward |
| Start | |
| B3 B3 O:0 |
[–––] [––––––––[OSR]–––––––––––––––––––––––––––––––––––––––––(L)––––––|
| 32 48 3 |
Rung 6:1
When the drill has drilled through the book, the body of the drill
actuates the DRILL DEPTH limit switch. When this happens, the DRILL
FORWARD signal is turned off and the DRILL RETRACT signal is turned on.
The drill is also retracted automatically on power up if it is not
actuating the DRILL HOME limit switch.
| Drill Drill |
| Depth LS Forward |
| I:0 O:0 |
|–+––––] [––––––––––––––––+––––––––––––––––––––––––––––+––––(U)–––––+–|
| | 4 | | 3 | |
| | 1’st |Drill | | Drill | |
| | Pass |Home LS | | Retract | |
| | S:1 I:0 | | O:0 | |
| +––––] [––––––––]/[–––––+ +––––(L)–––––+ |
| 15 5 2 |
Rung 6:2
When the drill is retracting (after drilling a hole), the body of the
drill actuates the DRILL HOME limit switch. When this happens the DRILL
RETRACT signal is turned off, the DRILL SEQUENCE START bit is turned off
to indicate the drilling process is complete, and the conveyor is
restarted.
| Drill |Drill Drill |
| Home LS |Retract Retract |
| I:0 O:0 O:0 |
|––––] [––––––––] [––––––––––––––––––––––––––––––––––––+––––(U)–––––+–|
| 5 2 | 2 | |
| | Drill | |
| | Sequence | |
| | Start | |
| | B3 | |
| +––––(U)–––––+ |
| | 32 | |
| | Conveyor | |
| | Start/Stop | |
| | | |
| | O:0 | |
| +––––(L)–––––+ |
| 0 |
Rung 6.3
| |
|–––––––––––––––––––––––––––––––––––––+END+–––––––––––––––––––––––––––|
| |