Meriam M2110L SMART LEVEL GAUGE - Manual (Page 3)

9R143 Dated 3/2011
1
LEVEL DISPLAY
Indicators
During normal operation, the gauge displays the level value in large numerals, and the bottom of the
display shows the current Engineering Unit. The top of the display will show PRGM when the gauge is in
Program Mode (flashing when “view only”). For SetPoint models, the top of the display will show
SET1/SET2 to indicate activated outputs (or corresponding register opened in Program Mode). For
Current Loop models, the top of the display will show 4-20mA when the output is enabled (or
corresponding register opened in Program Mode).
Performance
The M2110L Smart Level Gauge retrieves analog data from its pressure sensor, and performs an analog-to-
digital (A/D) conversion for microprocessor-based data handling. The rate of A/D conversion will
typically be between 9 to 13 conversions per second, depending on the various operating conditions.
To make the display easier to read, only every fourth sample is updated on the display. (This results in a
display update rate of about 3 updates per second.) The internal calculations, outputs, and serial interface
are updated at the full conversion rate.
Resolution
The Smart Gauge has a 4½ digit display. The resolution of the data (decimal point positioning) is defined
by the range and sampling process. The resultant full scale display and data resolution is summarized in
the table below. Note that since the Smart Level Gauge display is primarily user-scaled to level units, the
full scale and resolution depends on the scale. If a specific value will not fit on the 4½ digit display,
however, the auto-range feature will decrease the resolution to allow the value to fit the display (for
example, increasing past 199.99 becomes 200.0). The auto-range feature restores the decimal resolution
with a built-in deadband of 5 display counts (for example, 200.0 must drop to 199.95 before the two-digit
decimal resolution is restored).
Note that the full scale display indication during power-up will not necessarily have the same decimal
resolution found during actual level monitoring.