User Manual
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The
becomes an “ACCEPT” key. At each point, pressing
accepts the new calibration value and steps you to the next adjustment
(or out of CAL mode if there are no more steps).
To bypass a calibration step, just press to accept the present
value as is.
b. Leaving Calibration
Calibration is complete when the “CAL” icon goes out. Pressing any
measurement key cancels changes not yet accepted and exits calibration
mode.
Leaving pH after the 2nd buffer results in the same gain being entered
in place of the 3rd buffer.
2. Calibration Limits
There are calibration limits. A nominal “FAC” value is an ideal value
stored by the factory. Attempts to calibrate too far, up or down, from
there will cause the displayed value to be replaced with “FAC”. If you
accept it (press the “Cal” key), you will have the original default factory
calibration for this measurement. The need to calibrate so far out that
“FAC” appears indicates a procedural problem, wrong standard solution,
a very dirty cell cup or an aging pH/ORP sensor (ref. Troubleshooting
Chart, pg. 34).
C. Calibration Procedures
1. Conductivity, MIN/SALT or TDS Calibration
a. Rinse conductivity cell three times with proper standard (KCl,
NaCl, or 442) (ref. Cond/TDS Standard Solutions, pg. 36).
b. Rell conductivity cell with same standard. NACL-7500 shown.
c. Press
,
MIN
SALT
or
, then
press
, “CAL” icon will
appear on the display
(see Figure 4).
d. Press or to
or
to step the displayed value toward the standard’s value (7582
Figure 4
°C
NaCl
COND
CAL
µS
7582
23.8