Rockwell Automation Publication 1769-UM021G-EN-P - October 2015
205
Use I/O Modules with CompactLogix 5370 L2 Controllers
Chapter 8
Where:
Analog Read (Input) Data Value Channel x is the data read from the field device that is connected to the channel.
Timestamp Value is the timestamp of when data was received at the corresponding channel.
Cold Junction Compensation value is the converted CJC data. The data is calculated in the following manner:
•
If the CJC is open, the converted value is
25 °C (77 °F).
•
If the CJC is not opened and the Update CJC sensor every other scan option is disabled, the converted value is
25 °C (77 °F).
•
If the CJC is not opened and the Update CJC sensor every other scan option is enabled, the converted value is
the measured temperature.
S
Sign bit
Nu
Bit not used
SI
x
General status bit for an input channel. Bits 0
…3 are for input channels. Bit 4 is for CJC. If the bit is 0, the channel is operating normally. If the bit is 1, a fault has occurred
on the channel.
OI
x
Overrange alarm bit for an input channel.
0 = Channel is operating normally
1 = Input signal is over normal range.
UI
x
Underrange alarm bit for an input channel.
0 = Channel is operating normally
1 = For bits 0
…3, that is, input channels, the input signal is under the normal range. For bit 4, that is, channel using the thermocouple/mV, RTD/Resistance input type, the
input value equals the minimum value of the range.
HI
x
High alarm bit for an input channel 0.
0 = Channel is operating normally
1 = Input signal is above the user-defined range
LI
x
Low alarm bit for an input channel 0.
0 = Channel is operating normally
1 = Input signal is below the user-defined range.
OCx
Open circuit detection bit.
0 = Channel is not experiencing an open circuit condition
1 = Channel is experiencing an open circuit condition
SO
x
General status bit for output channel 0 or 1.
0 = Channel operating normally
1 = A fault has occurred on the channel
OO
x
Overrange alarm bit for output channel 0 or 1.
0 = Channel is operating normally
1 = Output signal is over the normal range
UO
x
Underrange alarm bit for output channel 0 or 1.
0 = Channel is operating normally
1 = Output signal is below the normal range
Table 16 - CompactLogix 5370 L2 Controller Embedded Analog I/O Module Input Data Array
Word
Bit
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
