Extech Instruments 407910 User manual

User's Guide
Heavy Duty
Differential Pressure Manometer
Model 407910

Model 407910 - Version 2.0 - March 2005
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Warranty
EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects
in parts and workmanship for one year from date of shipment (a six month limited warranty
applies to sensors and cables). If it should become necessary to return the instrument for
service during or beyond the warranty period, contact the Customer Service Department at
[phone] ext. 210 for authorization or visit our website www.extech.com for contact
information. A Return Authorization (RA) number must be issued before any product is
returned to Extech. The sender is responsible for shipping charges, freight, insurance and

Model 407910 - Version 2.0 - March 2005
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Specifications
General Specifications
Circuit Custom one-chip LSI microprocessor circuit
Display 0.6" (16mm) 2000 count LCD with function indicators
Units of Measure mBAR, psi, kg/cm2, mm Hg, inches Hg, meter H2O, inches H2O
and Atmospheres
Input circuit Differential inputs (P1 and P2)
Data Hold Freezes displayed reading
Sensor Built-in piezoelectric sensors
Zero Adjust Front panel push-button
Sample rate 0.8 sec. (approx.)
Compatibility Air or non-corrosive and non-ionized gas
Auto Power OFF Meter turns off after approx. 10 minutes to conserve energy
Data Output RS-232 PC serial interface
Ambient conditions 32 to 122oF (0 to 50oC); < 80% RH
Battery power 9V alkaline battery
Power Consumption 6mA DC (approx.)
Dimensions 7.1 x 2.8 x1.3" (180 x 72 x 32 mm)
Weight 0.76 lbs (345 g)
Accessories Quick-disconnect fittings (2), rubber jacket, and 9V battery
Range Specifications
Range/Units (Max.) Resolution Accuracy
± 2000 mbar 1
± 29 psi 0.02

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Meter Description
1. LCD Display – Indicates the measurement data, unit of measure, and user alert
symbols as described in this manual
2. Push-buttons:
•POWER – Press to turn the meter ON or OFF
•HOLD – Press to freeze the displayed reading
•ZERO – Press to null the display (with fittings disconnected)
•RECORD/RECALL – Press to access the MIN/MAX recording mode as described
later in this manual
•UNIT – Press to select the unit of measure
3. 0.16” (4mm) Quick-disconnect fittings (supplied)
4. P1 Input – 0.16” (4mm) accepts quick disconnect connector
5. RS-232 PC interface jack (3.5mm) – For use with data acquisition software/hardware
interface kit model 407001
6. P2 input – 0.16” (4mm) accepts quick disconnect connector
7. Rubber protective holster (removable)
8. Battery compartment (on rear) – Remove rubber jacket to access compartment
456
1
2
3
7
8

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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 Displayed Symbol
MBAR "m" at bottom of the LCD and "Bar" at the top
Kg/cm2 Kg /cm2
mm of Hg mm /Hg
m H2O m H2O
Atmospheres ATP
PSI PSI
Inches of Hg in/Hg
Inches of H2O 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.

Model 407910 - Version 2.0 - March 2005
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MIN/MAX Record/Recall Mode
The Record/Recall function tracks the maximum and minimum readings for recall at any
time.
1. Press the RECORD/RECALL button once. The REC indicator will appear on the
display.
2. Press the RECORD/RECALL button again to view the highest (MAX) reading taken
since the RECORD/RECALL button was first pressed. The MAX indicator and
maximum reading will appear on the display.
3. Press the RECORD/RECALL button again, the MIN indicator and the minimum value
will appear on the display.
4. To return to normal operation, press and hold the RECORD/RECALL button until the
display indicators REC, MAX, and MIN disappear.
RS-232 PC Interface
The meter has a built-in RS-232 serial port for use with the optional PC Interface Data
Acquisition Software/Hardware kit Model 407001.

Support line [phone]
Technical support: Extension 200; E-mail: [e-mail]
Repair & Returns: Extension 210; E-mail: [e-mail]
Product specifications subject to change without notice
For the latest version of this User’s Guide, Software updates, and other
up-to-the-minute product information, visit our website: www.extech.com
Extech Instruments Corporation, 285 Bear Hill Rd., Waltham, MA 02451
Battery Replacement
When the low battery indicator LBT appears on the display or if the meter does not switch
on when the POWER button is pressed, it is necessary to replace the battery.
To replace the battery:
1. Remove the meter's rubber protective jacket by stretching it over the bottom of the
meter.
2. Pry open the battery compartment located on the back of the meter using a small coin
or screwdriver.
3. Replace the 9V alkaline battery
4. Replace the battery compartment cover and the protective jacket.
Useful Conversions
Useful conversion Factors
reilpitluMoTmorF
In of H255370.0gHfonIO
In of H245.2gHfomCO
mm of Hg In of H273930.0O
Calibration and Repair Services
Extech offers repair and calibration services for the products we sell. Extech also
provides NIST certification for most products. Call the Customer Service Department for
information on calibration services available for this product. Extech recommends that
annual calibrations be performed to verify meter performance and accuracy.
Copyright ©2005 Extech Instruments Corporation
All rights reserved including the right of reproduction in whole or in part in any form.
more infor for Extech 407910
Phone: [phone]
Email: [e-mail]
Web. www.airconcern.co.uk
Air Concern Ltd, Building 173 Curie Avenue Harvell Didcot, Oxfordshire