The fields within this section of the Flow Calculation tab display properties associated with the Turbine input for the calculation. The turbine section is displayed only if the AGA-7 flow calculation type is selected, (see The Type of Gas Flow Calculation).
You can configure these properties directly in ClearSCADA, or read the configuration into the ClearSCADA database (see Configure or Read the Flow Run Configuration).
- Input Type—you can select from one of the following input types:
- Telepace Long
- ISaGRAF integer
The availability of the fields in this section varies, depending on the Input Type.
-
Input Register—Define the address of the register that contains the input value. Valid register values are in the following ranges 30001 to 39998 and 40001 to 49998.
- Low Flow Pulse Limit—Set the number of pulses below which a low flow alarm will occur. When the number of pulses falls below the Low Flow Pulse Limit, pulses are not accumulated against volume or rate until the number of pulses rises above the low flow pulse limit again. Setting the low flow pulse limit to 0, disables low flow detect. The default value is 10.
- Low Flow Detect Time—Set the length of time the number of pulses needs to remain below the Low Flow Pulse Limit for a low flow alarm to occur. Valid values are from 1 to 60 seconds. The default value is 5.
The input alarms fields allow you to set the alarm limits for alarm types that have been enabled in the Input Properties section.
NOTE: The following fields are only available for use with RealFLO 6.79 and later.
Use the following to configure alarm limits:
- High-High Alarm—Set the high-high alarm value for the turbine pulse rate. A valid entry value is any value within the turbine pulse rate range that is higher than or equal to the value of High Alarm. This control is enabled if the High-High Alarm option is enabled on the Input Properties section.
- High Alarm—Set a high alarm value for the turbine pulse rate. A valid entry value is any value within the pulse rate range that is higher than the value of Low Alarm, and is lower than or equal to the value of High-High Alarm. This control is enabled if the High Alarm option is enabled on the Input Properties section.
- Low Alarm—Set a low alarm limit for the turbine pulse rate. A valid entry is any value in the pulse rate range that is lower than the value of High Alarm. This control is enabled if the Low Alarm option is enabled on the Input Properties section.
- Alarm Hysteresis—Set the hysteresis value for each configured alarm type. The hysteresis setting determines at what level alarms are cleared when the input variable reading returns to a non-alarm state. This setting reduces nuisance alarms around the alarm limit.
- Any value in the range 0 to 100 percent is valid when the Hysteresis Units are set for Percent, in the Input Properties section.
- Any value in the full-scale range of the input variable is valid when the Hysteresis Units is set to Engineering, on the Input Properties section.
- Default Value—Set the value for the input variable to use when alarms are enabled and the Values in Alarm option in the Input Properties section is set to Use Default Values.
Further Information
For more detailed information on these properties, see the documentation provided with the RealFLO application.