Extech Extech 407510 Manual

User's Manual

Heavy Duty Dissolved Oxygen Meter

Model 407510

Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176

FAX [phone] - TestEquipmentDepot.com

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
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.

oC/o

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
Cal key

16. O

2

17. Zero key

18. O

calibration key

2

19. % Salt key

F for

99 Washington Street
Melrose, MA 02176

Phone [phone]
Toll Free 1-800-517-8431

Visit us at www.TestEquipmentDepot.com

Back to the Extech 407510 Product Page

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407510 V7.0 10/06

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 O

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 display stabilizes.

7. Press the O

/DO selector to the O2 position.

2

Cal key and the display will indicate approx. 20.9 (typical O2 in air).

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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 O
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

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.

NOTE: 1% = 10 ppt (parts per thousand)

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

2. Press the Factor Adj. key once to add 100 meters, twice to add 200 meters, and so on.

3. Once the desired compensation is displayed, press the ALTITUDE key again to store

Taking Measurements

1. Immerse the probe in the solution under test. For best automatic temperature

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

4. Rinse the probe with clean water after each use.

/DO switch to the DO position. If the measured liquid is pure water or is known

2

display and S on the bottom portion of the LCD.

and an “H” on the lower portion of the LCD.

Maximum compensation is 3900 meters.

the value.

compensation, immerse the probe to a depth of at least 4" (10 cm).

ft/min (0.2 to 0.3 m/s). If the solution is standing, stir the solution with the probe or use
an agitator.

Oxygen in Air (O2) Measurements

Follow the same steps above for DO measurements except for the variations described below:

1. Slide the O

2. The display will indicate the oxygen air value in %.

/DO switch to the O2 position.

2

Temperature Measurements

The lower display will indicate the temperature of the measured solution. Press the oC/oF key to
change the temperature units.

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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 O

2. Turn the meter OFF and disconnect the DO probe.

3. Press and HOLD the O

4. Release the O

5. Connect the DO probe.

6. Wait several minutes for the reading to stabilize and then press the O2 CAL key.

/DO switch to the O2 position.

2

CAL key and then press the POWER key.

2

CAL key and then press the ZERO key.

2

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.

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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

Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176

FAX [phone] - TestEquipmentDepot.com

6

407510 V7.0 10/06

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.

Specifications

General Specifications

Circuit Custom one-chip LSI microprocessor circuit
Display Dual function 0.5" (13 mm) 1999 count LCD w/ contrast adjust
Measurements Dissolved O2: mg/l (milligrams per liter); Oxygen in air: %;

Data hold Data hold key freezes displayed reading
Sensor Structure Remote Polarographic Dissolved Oxygen Sensor

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: 32 to 122 °F (0 to 50 °C); Humidity: < 80% RH
Battery power 9V alkaline battery
Power Consumption Approx. 6.6 mA DC
Weight 0.74 lbs. / 335 g (including batteries & probe)
Dimensions Main instrument: 7.1 x 2.8 x1.3" (180 x 72 x 32mm)

Accessories Carrying case, 9V battery, and 5 membranes
Optional

accessories

Temperature: °C/°F

Temperature sensor: Precision thermistor

Probe: 4.9" x 0.8" length/diameter (125 x 20mm)

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% O2 0.1 % O2 + 0.7% O2
Temperature

(probe only)
Compensation

adjustments

32 to 122 oF

o

0 to 50

C

o

F/C ±1.5

0.1

Temperature (automatic) 32 to 122 oF (0 to 50oC)

Salt 0 to 39% (1% = ppt)

+

0.8 oC

o

F

Altitude 0 to 3900 meters

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