Rockwell Automation 1772-LV Mini-PLC - 2/15 Programmable Controller (Series B) Programming and Operations - Manual (Page 119)

Programming Applications
Chapter 9
9Ć2
Figure 9.1
Converting Temperature Values
200
100
X
203
900
G
200
100
G X
202
000
Rung 1
203
900
:
206
000
G
204
005
G :
205
180 .
Rung 2
205
180
+
210
212
G
207
032
G
Rung 3
210
212
TON
033
1.0
G
211
190
<
Rung 4
PR 033
AC 000
15
011 033
15
Rung 5
CTU
034
PR 999
Rung 6
AC 007
033
17
210
212
L
011
G
220
212
=
Rung 7
16
110
14
U
011
Rung 8
16
Rung 1: The get instruction at address 200 multiplies the temperature 100 0 C by
9 and the result, 900 is stored in address 203.
Rung 2: The get instruction at address 203 divides 5 into 900 and stores the
quotient, 180, in address 205.
Rung 3: The get instruction at address 207 adds 32 to the value 180 which is
located at get address 205. The sum of 212 is stored at address 210. Thus
100
0 C = 212 0 F.
Rung 4: If the displayed temperature is less than 180 0 F, the timer initiates
timing for 3 seconds.
Rung 5: If 3 seconds have elapsed, an output at address 01115 will energize a
heating device which will bring the temperature back into the desired range.