Extech Instruments 407510 User manual

User's Manual
Heavy Duty Dissolved Oxygen Meter
Model 407510

407510-EU-EN-V7.2-5/12
2
Introduction
Congratulations on your purchase of Extech's Heavy Duty Dissolved Oxygen / Temperature Meter
which simultaneously displays Dissolved Oxygen or Oxygen in air, and Temperature. Units of
measure are mg/l for Dissolved Oxygen, % for Oxygen in air, and oC/oF for temperature. Oxygen is
measured with a remote sensor that also contains a thermistor for measuring temperature.
Advanced features include RS 232 PC serial interface, data hold, auto shut off, and Min/Max/Avg
recording.
Meter Description
1. LCD Display
2. POWER ON/OFF key
3. Data HOLD key
4. °C/°F selection key
5. LCD Contrast Adjust
6. RECORD key
7. RECALL key
8. Factor adjust key
9. Probe head
10. Sensor body
11. Sensor plug
12. Sensor jack
13. RS-232 output jack
14. Battery cover (rear)
15. Altitude compensation key
16. O2Cal key
17. Zero key
18. O2calibration key
19. % Salt key

407510-EU-EN-V7.2-5/12
3
Getting Started
Note: The dissolved oxygen probe assembly may be shipped to you from the factory dry.
If the probe does not contain electrolyte solution, refer to the Electrolyte Replacement
section of this manual for the instructions for adding the electrolyte solution prior to
initial use.
Filling the Electrolyte Container Prior to Initial Use
1. Unscrew and remove the electrolyte container from the tip of the
probe.
2. Fill the electrolyte container with new electrolyte.
3. Screw the electrolyte container back onto the electrode holder
and probe handle. Excess Electrolyte may be forced out through
the threads. Wipe clean.
4. Lightly tap the probe to remove any air bubbles.
Calibration
For first time use or after long periods (several days) of non-use, calibrate the instrument using the
following steps. The procedure should be performed in an open, well-ventilated area.
1. Ensure that the sensor is DISCONNECTED from the meter.
2. Turn ON the meter.
3. Slide the O2/DO selector to the O2position.
4. Press the zero key to null the meter (the display should indicate "OO").
5. Connect the DO sensor to the top of the meter (remove the plastic probe head protective
cap).
6. Allow the meter to stand for at least five minutes until the most stable value is displayed.
7. Press the O2Cal key and the display will indicate approx. 20.9 (typical O2in air).

407510-EU-EN-V7.2-5/12
4
Dissolved Oxygen (DO) Measurements
Measurement Preparation
Before taking measurements, perform the calibration described above if necessary. In addition,
perform the % SALT and ALTITUDE compensation adjustments as described below:
% SALT Compensation
Slide the O2/DO switch to the DO position. If the measured liquid is pure water or is known not to
have a salt content, set the % Salt factor to 0%.
1. Press the % Salt key. The display will indicate 0% on the middle portion of the LCD display
and Son the bottom portion of the LCD.
2. Pressing the Factor Adj. key once will add 1% to the salt factor.
3. Press the Factor Adj. key until the correct factor is displayed.
4. Press the % Salt key to store the factor.
ALTITUDE Compensation
The meter has a default calibration for sea level operation (0 meters). Any significant deviation
from sea level requires a compensation adjustment. Perform the following steps to do so:
1. Press the ALTITUDE key and the display will indicate a “0” in the middle of the LCD and an
“H” on the lower portion of the LCD.
2. Press the Factor Adj. key once to add 100 meters, twice to add 200 meters, and so on.
Maximum compensation is 3900 meters.
3. Once the desired compensation is displayed, press the ALTITUDE key again to store the
value.
Taking Measurements
1. Immerse the probe in the solution under test. For best automatic temperature compensation,
immerse the probe to a depth of at least 4" (10 cm).
2. Wait until the display stabilizes.
3. The velocity of the liquid coming into contact with the probe must be at least 0.6 to 1 ft/min
(0.2 to 0.3 m/s). If the solution is standing, stir the solution with the probe or use an agitator.
4. Rinse the probe with clean water after each use.
Oxygen in Air (O2) Measurements
Follow the same steps above for DO measurements except for the variations described below:
1. Slide the O2/DO switch to the O2position.
2. The display will indicate the oxygen air value in %.
Temperature Measurements
The lower display will indicate the temperature of the measured solution. Press the oC/oF key to
change the temperature units.

407510-EU-EN-V7.2-5/12
5
Advanced Features
Data Hold
Press the Data Hold key to freeze the displayed value. The LCD will display DH for Data Hold mode
along with the held reading. Press the Hold key again to release the data hold function.
MIN/MAX/AVG Data Recording
When selected, the Data Recording function records the Min, Max, and Average readings. To start a
data recording session:
1. Press the RECORD key once. The REC indicator will appear on the display and the meter will
begin to record the lowest (min), highest (max), and average (avg) readings.
2. To recall the data, press the RECALL key once. The MAX indicator will appear along with the
highest reading recorded since the RECORD key was pressed.
3. Press the RECALL key again to view the MIN value.
4. Press the RECALL key again to view the AVG reading.
5. To exit the Record mode, press the RECORD key again. The display indicators REC, MIN,
MAX, and AVG will disappear.
Auto Power OFF
The meter includes an Auto shut off feature that preserves battery life. The meter will automatically
turn off if no function button is pressed in any 10 minute period. To disable this feature press the
RECORD key to engage the record function.
LCD Contrast Adjust
It may be necessary to adjust the display contrast due to a change in viewing angle or voltage drift.
Use the LCD Contrast adjustment located on the right side of the meter to set the preferred
contrast.
CPU Reset
Certain improper keystroke sequences can cause the meter to “hang” and become inoperable. The
following procedure will reset the meter.
1. Slide the O2/DO switch to the O2position.
2. Turn the meter OFF and disconnect the DO probe.
3. Press and HOLD the O2CAL key and then press the POWER key.
4. Release the O2CAL key and then press the ZERO key.
5. Connect the DO probe.
6. Wait several minutes for the reading to stabilize and then press the O2 CAL key.
RS-232 PC Interface
The meter includes a RS-232 serial data port. This interface was designed to operate with the
Extech Data Acquisition Software/Hardware kit Part No. 407001. This kit enables the user to
capture, store and display readings using a PC.

407510-EU-EN-V7.2-5/12
6
Probe Head Replacement
The probe head on the tip of the probe holds a thin Teflon® membrane and an electrolyte
container. Calibration or reading errors could indicate loss of electrolyte or a dirty/damaged
membrane. The membrane is very delicate and can easily be damaged if it comes in contact with
solid objects. Replacement probe heads are available from your local distributor.
Replacement procedure
1. Unscrew the probe head and electrolyte container from the probe handle and discard.
2. Fill the new probe head/electrolyte container with electrolyte.
3. Screw the probe head onto the probe handle. Excess electrolyte may be forced out through the
threads. Wipe clean.
4. Lightly tap the probe to remove any air bubbles.
1. Probe handle
2. Temperature sensor
3. Probe Head

407510-EU-EN-V7.2-5/12
7
Battery Replacement
The low battery indication LBT appears on the LCD when the battery runs low.
To replace the battery:
1. Remove the meter's rubber protective cover to access the rear battery compartment.
2. Remove the battery compartment cover using a small coin or screwdriver and remove the 9V battery.
3. Replace the 9V battery and reinstall the cover and holster.
You, as the end user, are legally bound (Battery ordinance) to return all used batteries and
accumulators; disposal in the household garbage is prohibited!
You can hand over your used batteries / accumulators at collection points in your community
or wherever batteries / accumulators are sold!
Disposal: Follow the valid legal stipulations in respect of the disposal of the device at the end
of its lifecycle
Specifications
General Specifications
Circuit Custom one-chip LSI microprocessor circuit
Display Dual function 13 mm (0.5") 1999 count LCD w/ contrast adjust
Measurements Dissolved O2: mg/l (milligrams per liter); Oxygen in air: %; Temperature:
°C/°F
Data hold Data hold key freezes displayed reading
Sensor Structure Remote Polarographic Dissolved Oxygen Sensor
Temperature sensor: Precision thermistor
Data recording Min/Max/Avg readings stored for later recall
Auto power off Meter turns off after 10 minutes
Sample rate 0.4 Sec (approx.)
Data Output RS 232 PC serial interface
Operating conditions Temperature: 0 to 50 °C (32 to 122 °F); Humidity: < 80% RH
Battery power 9V alkaline battery
Power Consumption Approx. 6.6 mA DC
Weight 335 g / 0.74 lbs.(including batteries & probe)
Dimensions Main instrument: 180 x 72 x 32mm (7.1 x 2.8 x1.3")
Probe: 125 x 20mm (4.9" x 0.8") length/diameter
Accessories Carrying case, 9V battery, and 5 membranes
Optional accessories Membranes, data acquisition software & RS232 interface cable
Electrical Specifications
Measurement Range Resolution Accuracy
Dissolved Oxygen 0.0 - 19.9 mg/L 0.1mg/L + 0.4 mg/L
Oxygen in air 0 - 100% O20.1 % O2+0.7% O2
Temperature (probe
only)
32 to 122 oF
0 to 50 oC
0.1oF/C ±1.5
oF
+0.8 oC
Temperature (automatic) 0 to 50oC (32 to 122 oF)
Salt 0 to 39%
Compensation
adjustments
Altitude 0 to 3900 meters
Copyright ©2012 Extech Instruments Corporation (a FLIR company)
All rights reserved including the right of reproduction in whole or in part in any form.
www.extech.com