Siemens SITRANS FUS1020, Manual, Page: 165 / 251

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1020NFM-1D
Section 6
To enter an Interface Vs alarm setpoint:
To activate numeric entry press the <Right Arrow>.
Use PC numeric keys or KeyPad to enter the Interface Vs value in meters-per second.
To store the data press <ENTER>.
Aeration %
The System 1020 surpasses all other transit-time systems in its ability to operate with substantial
aeration (caused by entrained gases, mixing condition or cavitation). Some applications may require
an alarm indication if aeration exceeds a particular level. The meter detects this aeration level and
provides this data as an output. The aeration percentage triggers the alarm relay whenever it meets or
exceeds the threshold you set in this menu cell. The aeration percentage (Vaer %) appears in the
Liquid Data section of the Diagnostic Menu. The digital display screen also shows the current aeration
percentage.
NOTE: Severely aerated conditions may induce flowmeter fault. The 50% default setting usu-
ally allows enough leeway for continued operation. For intermittent faults, see memory
interval in the Output Control menu.
To set the Aeration % alarm:
To move the cursor to activate numeric entry press the <Right Arrow>.
Use PC numeric keys or KeyPad to enter the Aeration percentage setpoint.
To store data press <ENTER>.
Makeup Latch
A fault condition (e.g., caused by an empty pipe or a transient loss of power, etc.) could temporarily
interrupt operation. After recovery from the fault, the meter executes an In-Process Makeup to restore
operating parameters. During the makeup the meter sets a Makeup Alarm flag, which clears upon
completion. Therefore, unless you were monitoring the unit continuously, you could miss the fact that
an In-process Makeup occurred.
The [Makeup Latch] alerts you that the system implemented a Makeup by holding the Makeup Alarm
active until you reset it manually by the simultaneous keystrokes: <Fn>6 (where “n” represents the
measurement channel). In addition, if the Datalogger is active with Status Alarms selected, generating
a Datalogger report will reset the Makeup Alarm Latch. This ensures that the alarm does not appear on
succeeding Datalogger reports. A Makeup Alarm appearing on a subsequent report indicates that an
In-Process Makeup must have occurred since the last Datalogger report.
To Enable (or Disable) the Makeup Latch:
To access the [Makeup Latch] option list press the <Right Arrow>.
Move the cursor to select either [On or Off] by pressing the <Up/Down Arrows>.
To turn Makeup Latch [On] or [Off] press <ENTER>.