horiba twinno3 Procedure

1
When using the meter for the first time, change the sensor cover.
Replace the existing sensor cover with
the filter paper holder cover provided.
4
Take the measurement.
Insert a filter paper.
Place the filter paper in the sensor unit, and close
the filter paper holder cover.
Drop the sampled fluid onto
the filter paper.
Guideline: 4 or 5 drops.
• Soil Measurement (Supplementary Information)
• The measurement procedure printed is just an example.
Soil with a moisture content of 25% has a soil-to-water ratio of
about 1:5. Measurement results are affected by the actual soil
moisture concentration.
• To eliminate the effect of the soil's moisture concentration, allow
the soil to air-dry, mix it with water in a ratio of 1 part soil to 5 parts
water, and sample the water from the top after the mixture has
settled.
• Accurate measurements can't be obtained from measuring fluid soil
suspensions (turbid samples). Use the dedicated filter paper to
perform measurement. You don't need the dedicated filter paper
when you have created your own method of removing suspended
particles using equipment such as a centrifugal separator or
general-purpose filter paper.
• The sensor is affected by light, so avoid direct sunlight.
• Measurement may be impeded in soil with significantly high electrical
conductivity, chloride ion (Cl - ) concentration or oil concentration.
• Using the Onguard Ag chloride ion removal precolumn sold by
Dionex is an effective way to remove chloride ions (Cl - ).
• Consumable parts (supplies)
Name
Replacement sensor
Dedicated filter papers
Filter paper holder cover
30 ppm dedicated standard solution (Y044)
300 ppm dedicated standard solution (Y042)
Measurement Procedure
Model B-342
2
Turn the power ON.
Press the ON/OFF switch.
Add the soil sample to water.
Add enough of the sample to 60 mL of water
to bring the total volume to 70 mL.
Press the MEAS switch.
Press
MEAS MEAS
MEAS
ON ON
/
OFF OFF
-
ppm NO
CAL CAL
3
Wait until the stability icon ( ) lights before
pressing the switch.
Part No.
90880009000
90880015000
90880016000
90880013000
90880011000
3
Calibrate the sensor to ensure correct measurement.
* Always calibrate the sensor at least once per day.
Add the standard
solution.
MEAS MEAS
ON
/ Press
OFF OFF
CAL CAL
300 ppm standard solution
Shake the soil-water mixture
for 1 minute.
5
Always rinse the sensor after use.
Rinse off the sensor with water.
• Procedure for Two Calibrations
(For More Accurate Measurement)
Select the two-calibration mode from the special setting modes.
Perform two calibrations when you want higher-precision measurement.
1. 1. Follow the steps below to set the two-calibration mode.
① Press and hold the MEAS switch for at least
5 seconds to enter the special setting modes.
All the LCD segments light, then the display
on the right appears.
② Press and hold the CAL switch until the
icon and the number 3 appear.
③ Press the MEAS switch once (0.5 second) to
display the number of calibrations currently set.
When one calibration is set, the number 1
appears.
④ Press the CAL switch to display the number 2.
⑤ Press the MEAS switch.
The two-calibration mode is now set, and the meter returns to the
standard measurement mode.
2. 2. Add some drops of the 30 ppm standard solution to the
sensor, and close the light shield cover.
3. 3. Press the CAL switch for at least 2 seconds.
The
4. 4. When the
the first calibration has been finalized.
The first calibration must be finalized before you can
perform the second calibration.
5. 5. Add some drops of the 300 ppm standard solution to the
sensor, and perform the second calibration by the same
procedure used for the first.
CODE: GZ0000096111
October, 2007
Press the CAL switch.
CAL CAL
Sample the clear fluid on top.
Sample the fluid after allowing the mixture
to settle for several minutes.
Note: Read the Instruction Manual in
addition to this procedure.
icon flashes.
icon changes from flashing to steadily lit,
© 2007 HORIBA, Ltd.
MEAS MEAS
ON ON
/
OFF OFF
-
ppm NO
3 CAL CAL
Press