Azbil JTD910S User Manual

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Chapter 3 Starting and Stopping this Device
(4) Checking the Settings
For information about setting the following descriptive parameters, see the operating manual for
the relevant communicator.
(i) Setting the alarm
Based on the results from the Preparation section, set the variables for the upper and lower limits of
the pressure frequency index.
Press Freq Index High Limit: The setting range is between 0.0 and 1.0.
Press Freq Index Low Limit: The setting range is between 0.0 and 1.0.
Next, set the operating mode of the pressure frequency index diagnostic alarm. Press Freq Index
Alarm Use: The possible settings are shown below.
Disabled: Alarm is not used.
Enabled (High): Upper limit only
Enabled (Low): Lower limit only
Enabled (High and Low): Upper and lower limits
(ii) Alarm detection
If a pressure frequency index alarm is detected, it is reported as the appropriate self-diagnostic
status. See section "4-4 Troubleshooting"
(iii) Sensor Selection and P Sampling Interval
The sensor and pressure sensor sampling interval can be set. Press Freq Index Sensor Selection:
The possible settings are shown below.
For a differential pressure (DP) gauge
DP, 120ms factory default
DP, 240ms
DP, 360ms
SP, 360ms
For a pressure gauge (GP) or absolute pressure gauge (AP)
DP, 120ms factory default
DP, 240ms
DP, 360ms
- Sensor selection
For a differential pressure gauge, an SP sensor can be selected in addition to a DP sensor. If an
SP sensor is selected, fluctuations in static pressure can be detected. Using the static pressure
fluctuations allows the monitoring of the state of the process or application in a perspective
different from that of differential pressure fluctuations.
For example, when the pressure frequency index is used to detect clogged connecting pipes, a
change in the pressure fluctuation frequency caused by clogging on one side may appear more
quickly in the static pressure than in the differential pressure. Therefore, the SP sensor has the
potential to detect clogging faster.
The pressure frequency index is calculated based on the data from the SP sensor, provided that
the pressure to be measured is sufficiently high and the SP sensor is capable of detecting pressure
fluctuations.

Azbil JTD910S Specifications

General

Brand	Azbil
Model	JTD910S
Category	Transmitter
Language	English