Meriam M2110F SMART FLOW GAUGE - Manual (Page 27)

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While the serial port is transferring data, the other functions of the gauge are paused to allow this task to complete.
In this paused state, the display is frozen and the outputs are not updating. Typically, the data transfers are very
short and thus the interruption is minimal. However, selecting a register for edit will completely stop normal gauge
operation, because the gauge is awaiting the operator’s input. During this state, the display is blanked and as soon as
the operator selection or entry is complete, the gauge resumes normal operation.
Warning
The Notice of “PAUSE Gauge Operation” near the top of the menu is a reminder about this explanation. It is
particularly important when a gauge is in service as an in-process instrument, since the gauge will not respond to
process conditions while it is paused.
11.4 TIMEOUT
When the menu is displayed, it has no impact on gauge operation or performance. Therefore, the menu will remain
displayed indefinitely, or until the operator takes action or the gauge is reset. When the gauge is stopped awaiting
operator input the gauge’s display is blanked and the outputs are frozen. In this state, if there is no terminal
keyboard activity for approximately one-minute, the operation will time-out and the gauge is returned to its
operating mode.
11.5 DATA MONITORING
Selecting “X” from the menu will EXIT the menu and begin data monitoring. If the gauge was in Program Mode,
it will be returned to Measure Mode to allow data monitoring.
During data monitoring, every analog-to-digital conversion from the pressure sensor is displayed on the terminal.
The additional load of the continuous serial communication will slightly reduce the overall performance of the
gauge. The resulting data rate will typically be about ten (10) conversions per second, depending on various
operating conditions. Note that the data sent to the terminal will be damped according to the damp rate set in
register P2.
The data includes the pressure value and Engineering Units, as well as the output status of either the relay SET1 ON,
SET2 ON or the 4-20 mA output value, if set. Note that this status indication is the internal calculated value, as
there is no feedback hardware on the gauge. "Over Pressure!” is indicated if the input pressure exceeds 120% of the
full-scale sensor range. This indication acts on the direct measurement of pressure regardless of the damp rate
setting.
If the gauge is taken out of serial Measure Mode the data monitoring function will pause with a message. The
menu is available at this time, as it is at any time, by hitting ENTER from the terminal. When the gauge is returned
to Measure Mode, if the menu was not activated, data monitoring will automatically resume.
Data logging can be accomplished be invoking the appropriate logging function of the terminal software.
To EXIT the data monitoring function, simply hit ENTER on the terminal to restore the menu.
11.6 LOCKOUT
If the lockout feature is active, see register P0, the serial menu will prompt for the lockout code if necessary. For
security purposes, an asterisk (*) is displayed instead of the character as it is typed. When entering a new lockout
code through the serial port, however the code is displayed as it is typed, since there is no confirmation step.