Underrange/Overrange Detection - Allen-Bradley 5069-IF8 User Manual

Underrange/Overrange Detection

Underrange/Overrange Detection detects when the 5069-IF8 module is
operating beyond limits set by the input range.
The module can read input signal levels outside the low and high signal values for
each input range. The signal limits to which the module can read are thresholds.
Only when the signal is beyond a threshold is an underrange or overrange
condition that is detected and indicated.
For example, if you configure a 5069-IF8 module channel to use the + 10V input
range, an overrange condition does not exist until the input signal exceeds 12V.
Table 9 lists the input ranges of the 5069-IF8 module and the thresholds in each
range before the module detects an underrange/overrange condition.
Table 9 - Input Signal Threshold Ranges
Input Type Range
Current (mA) 0...20 mA
4...20 mA
Voltage (V) ±10.00V
0...5V
0...10V
(1) Underrange is set at < 3 mA, but the I:Chxx.Data tag reports values as low as 0.0 mA. The condition is clamped when the signal
reaches 3 mA.
(2) The module has alarm deadband values for each range. The deadband lets a condition remain set despite it disappearing. For
example, if a module uses a Current input type in the 4...20 mA range and the signal value goes below 3 mA, the underrange
condition is triggered. Because of the 0.07 mA deadband, the condition is not cleared until the signal value reaches 3.07 mA.
For more information on Alarm Deadbands, see
The Disable All Alarms feature, does not disable the underrange/overrange
IMPORTANT
detection feature.
The Disable All Alarms feature disables alarms on the module.
Underrange/Overrange detection is not an alarm. It is an indicator that
channel data has gone beyond the absolute maximum or minimum,
respectively, for the channel range.
To disable the Underrange/Overrange detection feature, you must disable
the channel.
Underrange/overrange conditions are indicated when the following tags
change to 1:
• I.Chxx.Underrange
• I.Chxx.Overrange
For more information on how to use the module tags, see Appendix B,
Tag Definitions on page
Rockwell Automation Publication 5000-UM005B-EN-P - November 2015
Current/Voltage Analog Input Module Features (5069-IF8)
Underrange Threshold Overrange Threshold
< -0.07 mA
> 23.00 mA
(1)
< 3 mA
< -12.00V >12.00V
< -0.02V > 6.00V
< -0.04V > 12.00V
page 46.
133.
Chapter 3
(2)
Deadband
0.07 mA
0.04V
0.02V
0.04
Module
43