Hanna Instruments HI 98202 User Manual

pNa

HI 98202

Soft Water Tester

GENERAL INFORMATION

The pNa tester utilizes a sodium ion-selective
electrode to determine the activity of free sodium
in solution (pNa = -log aNa).

In dilute solutions, the activity coefficient is nearly
1 and in such solutions pNa is a good indicator
of the sodium ion concentration. The relationship
between the pNa scale and the g/L Na+ scale is
explained in the chart below.

A double junction reference is used to ensure a
highly stable reading. If you suspect that the
calibration has drifted, you can recalibrate the
meter by using a solution of known concentration.
Adjust the reading with the calibration trimmer.

HOW TO USE THE CHART

• Locate the pNa reading on the horizontal axis
of the chart.

• Move vertically upwards to intersect with the
45º line.

• Move horizontally and read the g/L Na value.
E.g. pNa = 1.4

g/L = 0.9

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OPERATION

• Remove the protective cap and
turn the pNa on, by sliding the
ON/OFF switch located on the top
of the meter.

• Immerse it into the solution to be
tested without exceeding the maxi­mum immersion level.

• Stir gently and wait for stable reading.

• Measurements are displayd in pNa unit. Use
the chart included in this instruction manual
to calculate g/L value.

• After use, switch the meter off, rinse the
electrode with water to minimize contamina­tion and replace the protective cap.

• Large differences in pNa readings (±0.5 pNa)
could be due to a dry electrode or lack in
calibration.

• To improve the performance of your tester,
immerse it in HI 7080 solution up to the
maximum immersion level at least once a
week.

CALIBRATION

• Immerse the tester in HI 7080 calibration
solution, without exceeding the maximum im­mersion level.

• Allow the reading to sta­bilize and with a small
screwdriver turn the cali­bration trimmer until the
display shows "1.0" pNa.

MAINTENANCE

In case of erroneous reading even after an
accurate calibration, the reference junction can
be contaminated or clogged.

Pull out 2 mm (1/8'') of the cloth junction to
renew the electrode reference (it is recommended
to cut the cloth leaving always at least 2 mm ­1/8'' over the reference compartment) and re­calibrate the meter.

The cloth junction can be pulled out approxi­mately 20 times. After that, the electrode should
be replaced.

ELECTRODE REPLACEMENT

For replacing the electrode contact your Dealer or
the nearest Hanna Service Center.

BATTERY REPLACEMENT

If display fades or the pNa switches off, the
batteries must be replaced.

Slide off the battery compartment cover and
replace all four 1.5V alkaline batteries while
paying attention to the correct polarity.

Batteries should only be replaced in a non­hazardous area using the battery type specified
in this instruction manual.

SPECIFICATIONS
Range 0.0 to 3.0 pNa

(23 to 0.023 g/L Na+)

Resolution 0.1 pNa
Accuracy (@20°C/68°F) ±0.2 pNa
Typical EMC Deviation ±0.1 pNa
Calibration Manual, 1 point
Environment 0 to 50°C (32 to 122°F);

RH max 95% RH

Battery Type 4 x 1.5V alkaline
Battery Life approx. 800 hours of use
Dimensions 175 x 41 x 23 mm

(6.9 x 1.6 x 0.9")

Weight 95 g (3.4 oz.)

ACCESSORIES
HI 7080L 2.3 g/L Na+ solution, 500 mL

bottle

HI 7080M 2.3 g/L Na+ solution, 230 mL

bottle

HI 7061M Cleaning solution, 230 mL bottle
HI 73202 Spare electrode
HI 731326 Calibration screwdriver (20 pcs)

WARRANTY

These meters are guaranteed for one year against defects
in workmanship and materials when used for their intended
purpose and maintained according to instructions. Probes
are guaranteed for six months. This warranty is limited to
repair or replacement free of charge. Damages due to acci­dent, misuse, tampering or lack of prescribed maintenance
are not covered. If service is required, contact the dealer
from whom you purchased the instrument. If under war­ranty, report the model number, date of purchase, serial
number and the nature of the failure. If the repair is not
covered by the warranty, you will be notified of the charges
incurred. If the instrument is to be returned to Hanna Instru­ments, first obtain a Returned Goods Authorization Number
from the Customer Service department and then send it
with shipment costs prepaid. When shipping any instru­ment, make sure it is properly packaged for complete
protection.

The pNa is in compliance with the CE directives.

IST98202 R5 05/05