Emerson Rosemount 644 Reference Manual page 36

Configuration
March 2021
Set damping value using LOI
Reference the figure below to find the damping configuration path on the LOI.
Figure 2-16: Set damping value using LOI
2.8.3 Configure alarm and saturation levels
In normal operation, the transmitter will drive the output in response to measurements
between the lower to upper saturation points. If the temperature goes outside the sensor
limits, or if the output would be beyond the saturation points, the output will be limited to
the associated saturation point.
The transmitter automatically and continuously performs self-diagnostic routines. If the
self-diagnostic routines detect a failure, the transmitter drives the output to configured
alarm value based on the position of the alarm switch. The Alarm and Saturation settings
allow the alarm settings (Hi or Low) and saturation values to be viewed and changed.
Failure mode alarm and saturation levels can be configured using a Field Communicator,
AMS Device Manager, and the LOI. The following limitations exist for custom levels:
• The low alarm value must be less than the Low Saturation level.
• The high alarm value 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.
See table below for the common alarm and saturation levels.
Table 2-4: Rosemount Alarm and Saturation Values
Units - mA
High alarm
Low alarm
High saturation
Low saturation
(1) Requires 0.1 mA gap between low alarm and low saturation values.
(2) Rail mount transmitters have a high saturation max of 0.1 mA less than the high alarm setting,
with a max value of 0.1 mA less than the high alarm max.
(3) Rail mount transmitters have a low saturation min of 0.1 mA greater than the low alarm setting,
with a minimum of 0.1 mA greater than the low alarm min.
36
(1)
(1)
Min Max
21 23
3.5 3.75
(2)
20.5 20.9
(3)
3.7 3.9
Reference Manual
00809-0200-4728
Rosemount NAMUR
21.75 21.0
3.75 3.6
20.5 20.5
3.9 3.8
Emerson.com/Rosemount