Hanna Instruments ph 301 ユーザーズマニュアル

e. Alkaline slope calibra-

tion value expressed
in mV/pH and dis-
played on the primary
LCD with the 3

buffer used to cali-
brate the offset on the secondary LCD.

For pH 302:

See program #3 (page 66).

TAKING REDOX MEASUREMENTS

pH300, pH 301 and pH302 have the capabil-
ity to take ORP measurements. An optional
ORP electrode must be used to perform these
measurements (see page 105).

For pH 300 or pH 302:

To get into the mV mode (ORP),
press RANGE.

For pH 301:

To get into the mV mode, press
mV.

To measure the mV of a so-
lution simply submerge the
ORP electrode tip (4 cm/1½")
into the sample to be tested.
Allow a few minutes for the
reading to stabilize.
The display will indicate the absolute mV value
(positive or negative).

For pH 300 and pH 302 only:

When values are less
than ±400 mV, tenths of
mV are displayed; for
values greater than
±400 mV, the decimal
digit disappears.

CAL

Rel mV

°C

RANGE

4 cm

Press UP or DOWN to get this information in
the following sequence:

a. Date of the last pH

calibration (month,
day and year)

b. Time when the last

pH calibration was
completed (hour and
minutes).

c. Offset calibration

value expressed in
mV and displayed on
the primary LCD
with the buffer used
to calibrate the off-
set on the secondary LCD.

The offset pH value should be between
±30 mV. For values between ±30 and
±60 mV change the reference electrolyte
and repeat the calibration procedure. For
values higher than +60 mV or lower than
-60 mV the electrode is no longer reliable.
See the electrode maintenance section
on page 84.

d. Acid slope calibra-

tion value expressed
in mV/pH and dis-
played on the pri-
mary LCD with the
2

buffer used to

calibrate the offset on the secondary LCD.

°C

DATE

CAL

TIME

CAL