Great Lakes Instruments 692P, Руководство пользователя

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PART THREE - OPERATION SECTION 6 - pH CALIBRATION
Rev. 9-898 Model 692P -39-
Selecting
This Method
Entering Calibration Points
(by qualified person)
1. With display in pH measuring mode, press EXAM/
CANCEL key to place display in “examination” mode.
2. Press NEXT key until display indicates “BUFFER CAL.”
3. Press
ï ï
key to make display indicate “tAbL.”
4. Press ENTER key to select “two-key” table method
(“OK” flashes to confirm entry).
# # #
1. The following table lists the selection of pH values and
their buffer formulations. Choose and note one or two
table pH values for use as the calibration point(s).
NOTE: When two calibration point values are selected,
they must be at least one table value apart from
each other (non-adjacent values).
Table E

BUFFER VALUES FOR
“TWO-KEY” TABLE METHOD
pH Buffer Value Buffer Formulation
1.09 HCl (DIN 19267)
1.68 Tetraoxalate (NBS 260-53)
3.56 Tartrate (NBS 260-53)
3.78 Citric acid (DIN 19266)
4.00* Pthalate (DIN 19266)
4.01 Pthalate (NBS 260-53)
4.65 Acetate (DIN 19267)
6.87 Phosphate (DIN 19266)
7.00 Phosphate
7.41 Phosphate (DIN 19266)
9.18 Borax (NBS 260-53)
10.00 (10 A on display)* Carbonate/bicarbonate
(0.5 Molar)
10.00 (10 b on display) Glycol
12.45 Calcium hydroxide (DIN 19266)
*Indicates default values for LO and HI BUFFER VALUES.
2. Press NEXT key until display indicates “LO BUFFER
VALUE.”
3. Use
ï ï
and
ñ ñ
keys to make display indicate the de-
sired value for the single or lower calibration point.