Meriam M202 Precision Absolute Manometer - Manual (Page 15)

M2 Series Instruction Manual 9R68-A
Mar, 2008
www.meriam.com
page 15 of 36
Pressure Corrected to Sea Level
Pressure reduction to Sea Level is required so that barometric
readings can be compared at different elevations. The correction to
sea level is done using a “hypsometric equation”. This equation
simulates a “fictitious column of air” which extends downward
from the instruments location to sea level. This fictitious column is
assumed to be similar to the actual air column over nearby lower
elevations. Some properties are related to observed conditions
while others must be assumed. Barometric pressures given by the
National Weather Service and used at airports are always corrected
to sea level.
To set the unit to display pressure corrected to sea level:
Keystroke Display
1. Determine the elevation of
the instrument above sea
level, in meters. 700 meters
will be used as an example.
2. From Measure Mode press
the PRGM key. Top line reads “PROGRAM
MODE”. Bottom line reads
“UNITS SELECT”.
3. Press the key 4
times.
Top line reads “PROGRAM
MODE”. Bottom line reads
“SEA LEVEL SELECT”.
4. Press the PRGM key. Top line reads “SEA LEVEL
SELECT”. Bottom line reads
either “ENABLE” or
“DISABLED”.
5. Press the or key
to indicate the correction
to sea level status.
Bottom line toggles between
“ENABLE” and
“DISABLED”.
6. To turn on the correction,
set ENABLED on the 2
nd
line & press the PRGM key.
-OR-
To turn off the correction, set
DISABLED on the 2
nd line
and skip ahead to step 12 .
Top line reads “VALUE=:
00000000”. Bottom line reads
“CHANGE?: NO”.