Rockwell Automation 1734-IT2I Thermocouple and RTD Input Module User Manual - Manual (Page 15)

Publication 1734-UM004F-EN-E - December 2012
About POINT I/O Modules 5
Use Module Alarms POINT I/O modules are capable of generating the following alarms.
• Overrange
• Underrange
• Level (low-low, low, high, high-high)
• Cold-junction Compensation (CJC) Fault (1734-IT2 only)
• Open-wire Detection
Overrange Alarm (1734-IT2I, 1734-IR2, and 1734-IR2E modules)
The channel overrange alarm is set if the input is greater than the maximum
temperature (thermocouple or RTD range dependent), millivolt (+75 mV) or
resistance (600
Ω ) range value, or above the maximum range of the
thermocouple or RTD.
The cold junction compensator has its own overrange alarm. If the CJC
temperature goes above 70
⋅ C, the overrange alarm is set.
Underrange Alarm (1734-IT2I, 1734-IR2, and 1734-IR2E modules)
The channel underrange alarm is set if the input is less than the minimum
temperature (thermocouple or RTD range dependent), millivolt (-75 mV) or
resistance (10
Ω ) range value, or below the minimum range of the
thermocouple or RTD.
The cold junction compensator has its own underrange alarm. If the CJC
temperature goes below 0
⋅ C, the underrange alarm is set.
Level Alarms (1734-IT2I, 1734-IR2, and 1734-IR2E modules)
The following level alarms are available.
• Low
1734-IR2E RTD Input Module
RTD Type Low Scaling
Endpoint High Scaling
Endpoint
O hms 100
Ω
200
Ω
100
Ω
Pt
α =
0.00385 Euro 32 °F (0 °C) 572 °F (300 °C)