Filter
Top Products
Procedure
1. Set Two-Phase Flow Low Limit to the lowest density value that is considered normal in
your process.
Values below this will cause the transmitter to post Alert A105 ().
Tip
Gas entrainment can cause your process density to drop temporarily. To reduce the
occurrence of two-phase flow alerts that are not significant to your process, set Two-Phase Flow
Low Limit slightly below your expected lowest process density.
You must enter Two-Phase Flow Low Limit in g/cm³, even if you configured another unit
for density measurement.
2. Set Two-Phase Flow High Limit to the highest density value that is considered normal in
your process.
Values above this will cause the transmitter to post Alert A105 (Two-Phase Flow).
Tip
To reduce the occurrence of two-phase flow alerts that are not significant to your process, set
Two-Phase Flow High Limit slightly above your expected highest process density.
You must enter Two-Phase Flow High Limit in g/cm³, even if you configured another
unit for density measurement.
3. Set Two-Phase Flow Timeout to the number of seconds that the transmitter will wait for
a two-phase flow condition to clear before posting the alert.
The default value for Two-Phase Flow Timeout is 0.0 seconds, meaning that the alert
will be posted immediately. The range is 0.0 to 60.0 seconds.
Detecting and reporting two-phase flow
Two-phase flow (gas in a liquid process or liquid in a gas process) can cause a variety of
process control issues. By configuring the two-phase flow parameters appropriately for
your application, you can detect process conditions that require correction.
Tip
To decrease the occurrence of two-phase flow alerts, lower Two-Phase Flow Low Limit or raise Two-Phase
Flow High Limit.
A two-phase flow condition occurs whenever the measured density goes below Two-Phase
Flow Low Limit or above Two-Phase Flow High Limit. If this occurs:
• A two-phase flow alert is posted to the active alert log.
• Line density is held at its last pre‐alert value for the number of seconds configured in
Two-Phase Flow Timeout.
If the two-phase flow condition clears before Two-Phase Flow Timeout expires:
Configure process measurement
Configuration and Use Manual 25