Emerson Rosemount 2140, Reference Manual, Page: 43 / 144

33
Reference Manual
00809-0100-4140, Rev AA
Configuration
January 2017
Configuration
2.10.2 Configuring alarm and saturation levels
Note
This function is available only when the Primary Variable (”PV”) is mapped to the Sensor
Frequency or Scaled Variable device variables.
The Rosemount 2140 continuously performs self-diagnostic routines. When there is a
device malfunction that is an alarm condition, the Analog Output current is driven to a
configured alarm level (see tables) based on the HI or LO alarm switch position (see
“Setting
the alarm switch” on page 46 ) and the ordered Alarm Level code.
In normal operation, the Analog Output current is driven in response to fork frequency
changes. If the fork frequency goes outside sensor limits (see
Table 2-4 on page 28 ), or if the
output current would be beyond the saturation points (see tables), the current is limited to
a saturation level based on the alarm switch position and the ordered Alarm Level code.
Table 2-5. Rosemount Alarm and Saturation Values (Alarm Level code C8)
Table 2-6. NAMUR-Compliant Alarm and Saturation Values (Alarm Level codes C4/C5)
Table 2-7. Custom Alarm and Saturation Values (Alarm Level code C1)
Failure mode alarm and saturation levels can be custom-configured using a Field
Communicator, AMS Device Manager, or the Local Operator Interface (LOI).
The following limitations exist for custom-configurable levels:

Low alarm level must be less than the low saturation level.

High alarm level must be higher than the high saturation level.

Alarm and saturation levels must be separated by at least 0.1 mA.
The configuration tool will provide an error message if the configuration rule is violated.
Note
When set to HART multi-drop mode, all saturation and alarm information is sent digitally;
saturation and alarm conditions will not affect the analog output.
See also
“Establishing multi-drop communications (optional)” on page 40 .
Level 4–20 mA saturation 4–20 mA alarm
Low (LO position) 3.9 mA

3.75 mA
High (HI position) 20.8 mA

21.75 mA
Level 4–20 mA saturation 4–20 mA alarm
Low (LO position) 3.8 mA

3.6 mA
High (HI position) 20.5 mA

22.5 mA
Level 4–20 mA saturation 4–20 mA alarm
Low (LO position) 3.7 mA to 3.9 mA 3.6 mA to 3.8 mA
High (HI position) 20.1 mA to 22.9 mA 20.2 mA -to 23.0 mA