Using module alarms, Fault mode select -7, Using module alarms -7 – Rockwell Automation 1797-IRT8 FLEX Ex Thermocouple/RTD/mV Input Module User Manual User Manual
Page 21: Overrange alarm -7, Fault mode select, Overrange alarm

Publication 1797-6.5.2 - February 2001
Understanding Configurable FLEX Ex Thermocouple/RTD/mV Input Module Features 2-7
Fault Mode Select
Select whether the channel fault detection is enabled or disabled for
channels 0-3 and 4-7.
Range: 0 = disable, 1 = fault detection enabled (wire off, mV
overvoltage, RTD open). Default = 0.
Using Module Alarms
FLEX Ex I/O modules are capable of generating four alarms:
•
Overrange
•
Underrange
•
Fault
•
Cold Junction Compensation (CJC) Fault
These alarm conditions are described in general terms and as they
relate to bits on the FLEX Ex I/O module on the following pages.
Overrange Alarm
The channel overrange alarm is set if the input is greater than the
maximum temperature (thermocouple or RTD range dependent),
millivolt (+100mV) or resistance (500
Ω
) range value.
Range: 0 = normal, 1 = input overrange. Default = 0.
This alarm stays active at any value above 100% of range and is
always enabled by the module. Refer to the figure below for the
sensor dependent signal which causes this alarm to be generated.
Bits 06-07
Fault Mode bits – when a bit is set (1), fault mode is enabled for that channel.
Bit 06 corresponds to channels 0-3; bit 07 corresponds to channels 4-7.
0 = disabled
1 = enable wire-off detection