Rockwell Automation 1756-OF8I ControlLogix Eight-channel Isolated Analog I/O Modules User Manual
Page 36
36
Rockwell Automation Publication 1756-UM540A-EN-P - May 2014
Chapter 2
ControlLogix Isolated Analog I/O Module Features
The following table lists the resolution for each module’s input/output range and
corresponding range capability.
Table 2 - Module Resolution in Various Configuration Selections
Module
Mode
Available Input/
Output Range
(1)
Actual Input/Output
Range Capability
Number of Bits
Across the
Theoretical
Operating Range
Number of Bits
Across the Actual
Range Capability
Resolution (signal
per count)
1756-IF8I
Voltage
-10…10V
0…10V
0…5V
-10.5…10.5V
0…10.5V
0…5.25V
24 bits
23.75
22.75
21.75
1.49 μV/count
Current
0…20 mA
0…20 mA (sourcing)
0…21 mA
0…21 mA (sourcing)
22.74
2.99 nA/count
1756-IRT8I
Thermocouple
-100…100 mV
-101…101 mV
24 bits
23.98
0.01 μV/count
RTD
1…500
Ω
2…1000
Ω
4…2000
Ω
8…4000
Ω
0…510
Ω
0…1020
Ω
0…2040
Ω
0…4080
Ω
23.98
0.06 m
Ω
/count
0.12 m
Ω
/count
0.25 m
Ω
/count
0.50 m
Ω
/count
1756-OF8I
Voltage
-10…10V
0…10V
0…5V
-10.5…10.5V
0…10.5V
0…5.25V
16 bits
16.00
0.32 mV/count
0.16 mV/count
0.08 mV/count
Current
0…20 mA
0…21 mA
16.00
0.32 μA
(1) These ranges represent the range choices available in the Logix Designer application.
IMPORTANT
Because these modules must allow for possible calibration inaccuracies,
resolution values represent the available Analog-to-Digital or Digital-to-
Analog counts over the specified range.
Additionally, RPI and Notch Filter settings affect module resolution on the
1756-IF8I and 1756-IRT8I modules. For more information, see
, respectively.