Download Configuration and Use Manual
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Configure process measurement You must enter Two-Phase Flow Low Limit in g/cm³, even if you configured another unit for density measurement. The default value for Two-Phase Flow Low Limit is 0.0 g/cm³. The range is 0.0 to 3.0 g/cm³. 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/cm, even if you configured another unit for density measurement. The default value for Two-Phase Flow Low Limit is 3.0 g/cm³. The range is 0.0 to 3.0 g/cm³. 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: • Line density reverts to actual process density. • The two-phase flow alert is deactivated, but remains in the active alert log until it is acknowledged. If the two-phase flow condition does not clear before Two-Phase Flow Timeout expires, line density reverts to actual process density, but the two-phase flow alert remains active. Configuration and Use Manual 27