Delta HD2105.1, Operating Manual

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HD2105
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V2.3
5) To proceed with the calibration press ENTER. The electrode offset mV value (OFFS) is shown
on the display for few seconds.
After a few seconds the instrument shows the measurement again, corrected according to the
new calibration,
but remains in calibration mode .
Pressed repeatedly the ENTER key allows the calibration on the point to be repeated, for exam-
ple, in order to obtain a more stable value.
6) To end the electrode calibration, press pH/mV (ESC) to exit calibration, or continue the calibra-
tion for the second point.
7) Extract the electrode from the buffer, clean it carefully, and insert it in the following buffer.
8) Press MENU.
The instrument displays the value detected on the new buffer: continue by repeating the steps from
point 3.
NOTES:
•
After calibration, the instrument displays an electrode quality indication :
•
No signal: electrode functioning.
•
1 small square blinking on the lower right: electrode almost exhausted.
•
2 small squares blinking on the lower right: electrode exhausted to be replaced.
•
The 3 point calibration must always be carried out according to the fixed sequence:
NEUTRAL>>ACID>>BASIC
. The basic buffer must be the last in the sequence.
•
Without having pressed ENTER at all, the calibration is interrupted by pressing pH/mV
(ESC);
the previous values will continue to be used.
•
The buffers are always presented in the sequence set in the menu with the BUFR_1-BUFR_2-
BUFR_3 parameters. The 2 point calibration is possible using the sequence BUFR_1-BUFR_2
or BUFR_2-BUFR_3 or even BUFR_1-BUFR_3.
The 3 point calibration is only possible us-
ing the exactly described sequence BUFR_1-BUFR_2-BUFR_3.
Allowed calibration sequences:
Nu
m
b
er of
cal
ib
rat
ion
points
1 BUFR_1 BUFR_2 BUFR_3
2 BUFR_1 - BUFR_2 BUFR_2 - BUFR_3 BUFR_1 - BUFR_3
3 BUFR_1 - BUFR_2 - BUFR_3
•
A buffer can be disabled in the option selection phase (MENU mode) by choosing the NIL
value. In this case, the disabled buffer is excluded from the sequence and will not be proposed.
•
If no other buffer is expected after the first, as the BUFR_2 and BUFR_3 have been set to NIL,
the calibration mode is exited by pressing MENU.
•
In any case where no operation is performed, the calibration mode automatically stops af-
ter 60 seconds.
•
If the calibration is rejected by the instrument because it is considered to be excessively cor-
rupted, the
CAL ERR message will appear, followed by a long beep. The instrument remains in
calibration mode and maintains the previous calibration values: at this point, if the calibration is
interrupted using ESC, the instrument signals the anomaly through the CAL message blinking.