Allen-Bradley 1747-SN User Manual page 153

7–20 Application Examples
Rung 2:9
This rung checks the analog input data (4–20MA input) to ensure that it is within the proper range
and turns on outputs for under and over range. If the value is within range it is scaled to the
4–20MA analog output range and is then placed into the BTW data area. The BTW enable bit and pending
bits are then latched to initiate the BTW to the analog combination module, output 0. Output 0 is
connected to a meter to display the current range in percent.
|
| GOOD BTR
| DATA BIT
| B3:0 +LES–––––––––––––––+
|––] [––+–+LESS THAN
| 2 | |Source A
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| | |Source B
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| | +––––––––––––––––––+
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| | +GRT–––––––––––––––+
| +–+GREATER THAN
| | |Source A
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| | |Source B
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| | +––––––––––––––––––+
| | +LIM–––––––––––––––+
| +–+LIMIT TEST
| |Low Lim
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| |Test
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| |High Lim
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| +––––––––––––––––––+ |
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Rung 2:10
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|––––––––––––––––––––––––––––––––––––––––––––––––+END+–––––––––––––––––––––––––––––––––––––––––––|
|
Publication 1747 6.6 - July 1996
+–––––––––––––––––––––––––––––––––––––––––––––––––––––––––(L)–––––+–|
N7:10|
0|
3277|
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+–––––––––––––––––––––––––––––––––––––––––––––––––––––––––(L)–––––+ |
N7:10|
0|
16384|
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+–+–––––––––––––––––––––––––––––––+SCALE
3277| |
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N7:10| |
0| |
16384| |
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| BTW ENABLE|BTW DONE
| BIT |BIT
| M0:1.200
+––––]/[––––––––]/[–––––+––––(L)––––––––––––+––––––––+
15
+SCL–––––––––––––––+
|Source
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|Rate [/10000] 5250| |
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|Offset
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|Dest
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+––––––––––––––––––+ |
SERVICE
THE BTW
STATUS/
BTW
PENDING
M1:1.200 B3:0
13 | 1
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| BTW ENABLE
| BIT
| M0:1.200
+––––(L)––––––––––––+
| 15
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| B3:0
|––––––––(U)––––––––|
2
BELOW
RANGE FLAG
O:2.0
0 | |
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ABOVE | |
RANGE FLAG | |
O:2.0 | |
1 | |
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+–+––––––––––+ |
N7:10| |
0| |
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4522| |
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M0:1.210| |
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