407910 Datasheet, PDF (5/7 Pages) Extech Instruments Corporation. – Heavy Duty Differential Pressure Manometer

Basic Operation
Meter Power
This device uses a 9V battery for power. If the meter does not switch on when the POWER
button is pressed or if the display shows LBT, replace the battery (refer to the Battery
Replacement section later in this manual).
In order to conserve battery life, the meter has an automatic power off feature (after 10
minutes). To defeat this feature, access the RECORD mode by pressing the
RECORD/RECALL button. In the RECORD mode, the meter will remain on until the user
turns it off or until the battery weakens.
Unit of measure
Press the UNIT button to select the unit of measure. This meter offers eight (8) units of
measure as listed below, in the specifications chart earlier in this manual, and on the face-
plate of the meter.
Units
MBAR
Kg/cm2
mm of Hg
m H₂O
Atmospheres
PSI
Inches of Hg
Inches of H₂O
Displayed Symbol
"m" at bottom of the LCD and "Bar" at the top
Kg /cm²
mm /Hg
m H₂O
ATP
PSI
in/Hg
inch H₂O
Zero Adjust and Offset function
Before use and without fittings attached to the meter, press the ZERO button to calibrate
the meter’s circuitry. The display should then indicate zero.
If it is desired to offset the meter’s display, press the ZERO button while taking a
measurement. Subsequent readings will be the difference between the current
measurement and the measurement that was on the display when the ZERO button was
pressed.
Fittings Connection
Connect tubing to the quick-disconnect fittings and then snap the supplied quick-
disconnect fitting(s) to the P1, P2 (or both) input port(s). If both inputs are used (differential
mode), the meter displays a positive pressure reading if the P1 pressure is greater than P2
and a negative reading if P2 is greater than P1.
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Model 407910 - Version 2.0 - March 2005