Rockwell Automation 1761 MicroLogix 1000 Programmable Controllers - Manual (Page 131)

Using Comparison Instructions
7–9
Beginning a Subroutine in File 7
This section of ladder keeps track of the total inches of paper the current drill bit has
drilled through. As the current bit wears out, a light illuminates on the operator
panel, below, to warn the operator to change the drill bit.
For 32 I/O controllers: If the operator ignores this warning too long, this ladder
shuts the machine down until the operator changes the bit.
OPERATOR PANEL
Start I/6 Stop I/7
Change Tool Soon
O/4
Change Tool Now
O/6
Thumbwheel for
Thickness in 1/4”
Tool Change Reset 5 Hole
7 Hole 3 Hole
I/9–I/10 I/11–I/14
(Keyswitch)
I/8
Rung 7:0
➀
Examines the number of 1/4 in. thousands that have accumulated over
the life of the current drill bit. If the bit has drilled between
100,000–101,999 1/4 in. increments of paper, the ”change drill” light
illuminates steadily. When the value is between 102,000–103,999, the
”change drill” light flashes at a 1.28 second rate. When the value
reaches 105,000, the ”change drill” light flashes, and the ”change
drill now” light illuminates.
| 1/4 in. 100,000 |
| Thousands 1/4 in. |
| increments |
| have |
| occurred |
| +GEQ–––––––––––––––+ B3 |
|–––+–+GRTR THAN OR EQUAL+–––––––––––––––––––––––––––––––––( )–––––+–|
| | |Source A N7:11| 16 | |
| | | 0| | |
| | |Source B 100| | |
| | | | | |
| | +––––––––––––––––––+ | |
Programming