Channel configuration, Ladder program, Channel configuration ladder program – Rockwell Automation 1746-NI8 SLC 500 Analog Input Modules User Manual User Manual
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Variable Content
TTL:Chap
C–3
Publication 1746Ć6.8 - April 1997
For the 1746-NI4, input selection (voltage or current) is made via a
switch. For the 1746-NI8, input selection (voltage or current) is
made via a switch and a configuration word is used to define the
other operating parameters for the module. The 1746-NI4 does not
employ a configuration word.
To configure the 1746-NI8 for the same input type as the 1746-NI4,
use the following configuration word. For voltage input you must
select
±
10V dc, and for current input you must select
±
20 mA.
Define a configuration word for channels 0–7 on the 1746-NI8
module.
•
Input Type
•
Data Format
•
Open Circuit
•
Filter Frequency
•
Channel Enable
•
Not Used
Current Input
Voltage Input
ЙЙЙЙЙЙЙ
ЙЙЙЙЙЙЙ
ЙЙЙЙЙЙЙ
11
12
13
14
15
0
0
0
0
9
10
8
6
7
4
5
0
1
2
3
0
0
0
0
Bit Number
1
1
0
0
0
1
1
1
1
0
0
0
1
1
0
0
0
1
1
0
0
0
0
0
Bit Definitions for Converting from 1746ĆNI4 to 1746ĆNI8:
Bits 0-2
Input Type
000 =
±
10V dc
110 =
±
20 mA
Bits 3- 5
Data Format
011 = 1746ĆNI4 data format
Bits 6 and 7
Open Circuit
00 = zero (the open circuit option is not available for the
±
20 mA data type)
Bits 8-10
Filter Frequency
100 = 10 Hz
Bit 11
Channel Enable
0 = channel disabled
1 = channel enabled
Bits 12-15
Not Used
0000 = always make this setting
See chapter 5 for more detailed information on channel
configuration.
To convert your ladder program from the 1746-NI4s to a 1746-NI8,
you only need to change the module addressing. Change the
addresses in the program (slot and word sub element number) to
reflect the location of the new module.
See chapter 6 for more information on ladder programming.
Channel Configuration
Ladder Program