Hanna Instruments HI 4013 User Manual

Page 15

XIII

XIII. pH and Interferents

pH and Interferents

HI 4013/ HI4113 Nitrate electrodes can operate over a pH
range of 3 to 8 but better results are found if pH is kept
constant throughout calibration and test. Sulfuric acid or
NaOH can be used for pH adjustment or use ISISA to surpress
interferences and buffer pH. Limiting the length of time of
exposure to samples containing interferences will prolong
useful life of your electrode. If sensor has been exposed to
ions above recommended levels, soaking in pure nitrate
solutions without ISA will aid recovery of function.

XIV.

XIV. Storage and Care of the HI 4013 and

Storage and Care of the HI 4013 and

HI 4113 electrodes

The HI 4013 sensor can be stored in standards that do not
contain ISA for short time periods. For long term storage,
unscrew sensing module from sensor handle and store dry
in the shipping vial.
The model HI 4113 combination electrode can be left in
dilute standards that do not contain ISA for short time
periods. If the electrode will be used frequently and needs
to be ready for use, take measures to prevent evaporation of
fill solution. Top off fill solution, replace o-ring, fill hole
cover on the fill hole opening, and place sensor in dilute
nitrate solution that does not contain ISA. Store electrode
upright. Prior to use, drain electolyte chamber and refill
with fresh HI 7078 fill solution.
For long term storage, the electrode should be drained,
disassembled and washed of salts with deionized water.
Wrap the ceramic junction in Parafilm® or other sealing
wrap. Unscrew the module and store dry in the shipping
vial. Refrigeration of module will extend its life. Store dis-
assembled electrode in storage box provided with electrode.

XV.

XV. Conversion tables

Conversion tables

For NO

33333

-----

Multiply by

Moles/L (M) NO

to ppm NO

(mg/L)

62000

ppm (mg/L) to M (moles/L)

1.61 X 10

-5

This manual is related to the following products:

HI 4113