Great Lakes Instruments 692P, Руководство пользователя

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PART THREE - OPERATION SECTION 6 - pH CALIBRATION
Rev. 9-898 Model 692P -35-
6.4 “Two-Key”
Two-Point Method
NOTE: Entry value must be between 0.00 and 10.00 pH
and at least 1.00 pH lower than the value of the
higher calibration point.
5. Press ENTER key to enter value (display flashes “OK” to
confirm entry and returns to pH measuring mode).
NOTE: If display indicates “Err 1” diagnostic message,
ignore it and proceed with step 6. This message
indicates that the new LO CAL VALUE entry is
significantly different than the previously entered
calibration values. After the HI CAL VALUE is
entered (step 10), the “Err 1” message will cancel
and the display will return to normal indication.
6. Remove sensor from lower value buffer. Rinse sensor in
clean water and place in higher value buffer. Allow sen-
sor to attain temperature equilibrium with the buffer.
7. Press EXAM/CANCEL key to place display in “examina-
tion” mode.
8. Press NEXT key twice to make display indicate pH “HI
CAL VALUE.”
9. Use
ï ï
and
ñ ñ
keys to make display indicate the value
of the higher pH buffer (from table on buffer bottle).
NOTE: Entry value must be between 2.00 and 12.00 pH
and at least 1.00 pH higher than the value of the
lower calibration point.
10. Press ENTER key to enter value (display flashes “OK” to
confirm entry and returns to pH measuring mode).
“VALUE ERROR” flashes if the difference between entry
values is less than 1.00 pH.
This completes the conventional two-point pH calibration.
Use the conventional two-point method (Section 6.3) to ini-
tially calibrate the instrument, including when the pH sensor
has been replaced. Thereafter, you can use the “two-key”
two-point method, but first a qualified person must:
n
Set the instrument for this method.