2. Specifications
2.4. Functions
44
Analog Input Module 2MLF-AV8A, AC8A User's Guide
R200
Honeywell
September 2010
Function to detect input signal failure/disconnect
1.
Input Range
This detection function is available only if the input signal range is 1 ~ 5V or 4 ~ 20mA.
Detection conditions for respective input signal ranges are as described in the below
table.
Input signal
range
Voltage/Current value regarded as disconnected
1 ~ 5V
0.2V or less
4 ~ 20mA
0.8mA or less
2.
Disconnection display for respective channels
Detection status bit of signal failure/disconnect for respective input channels is saved
on UXY. 10. (X denotes Base No., and Y denotes Slot No.)
Bit
15
14
13
12
11
10
9
8 7
6
5
4
3
2
1
0
Default
0
0
0
0
0
0
0
0 0
0
0
0
0
0
0
0
Assigned
-
-
-
-
-
-
-
- CH7
CH6
CH5
CH4
CH3 CH2
CH1
CH0
BIT
Description
0
Normal
1
Disconnected
3.
Operation
Each bit is set to 1 if an assigned channel is detected as disconnected, and is set back
to 0 when the channel is connected back again. In addition, each bit can be used to
detect the disconnection in the user program together with execution conditions.
4.
Program example
A program example of analog input module installed on Base No. 0 and Slot No. 2
detecting a input signal failure/disconnect and storing the respective channel number
on the P area.
(System configuration)
