Meriam M2110P SMART PRESSURE GAUGE - Manual (Page 25)

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User’s Manual Dwg No 9R141-IR
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.
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, however, the gauge’s display is blanked and the outputs
are frozen (for example, awaiting input while editing a register). 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.
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. The “X” menu item
will include this message as appropriate, when refreshed.)
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 as appropriate
(SET1 ON, SET2 ON, or the 4-20 mA value). Note that this status indication is the internal calculated
value, as there is no feedback hardware on the gauge. Finally, “Over Pressure!” is indicated if the
input pressure exceeds 120% of the full scale sensor range (this indication acts immediately, regardless
of the damp rate setting).
If the gauge is taken out of 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.
LOCKOUT
If the lockout feature is active (see register P0), the serial menu will prompt for the lockout code when
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.