1. Enter the
CAL
mode as previously described and step through the instructions until
CAL1
appears.
2. Press
^
and
v
together, the display will show a value with
CAL1
flashing every few seconds.
Allow time for this reading to stabilise (typically 20 seconds).
3. Press and release
F
, the display will show a value with
SCL1
flashing every few seconds.
4. Adjust the value displayed to the known solution value using the
^
and
v
pushbuttons.
5. Press and release
F
, the display will show
CAL
End followed by
CAL2
. If any other message
is seen (see “Error Messages” appendix) then the calibration will need to be repeated. If
required a second point,
CAL2
may now be taken. The second calibration point is normally
used only to compensate for head resistance when long cell cables are used or to improve
linearity when measuring over a wide conductivity range. In many installations the second
point is not require. If the second point is required move on to step 6, if this is not required
simply press and release
F
until the
FUNC End
message is seen or press
P
to escape to
normal measurement mode.
6. Clean the probe in pure water then insert into a second solution of known conductiv-
ity/resistivity/ ppm (the second solution must be at least 500uS/cm higher (or 10x lower
for resistivity or 500 ppm higher) in value from the first solution, see note below if it is not
possible to have a 500uS/cm difference (or 10x difference for resistivity or 500 ppm) in the
process you are using).
7. Press
^
and
v
together, the display will show a value with
CAL2
flashing every few seconds.
Allow time for this reading to stabilise (typically 20 seconds).
8. Press and release
F
, the display will show a value with
SCL2
flashing every few seconds.
9. Adjust the value displayed to the known solution value using the
^
and
v
pushbuttons.
10. Press and release
F
, the display will show
CALEnd
to indicate that calibration is complete.
Note: If the range you are using does not allow for a 500uS/cm difference (or 10x difference for
resistivity or 500 ppm) between
CAL1
and
CAL2
then you should use the Null Calibration
and
CAL1
only. The solution used for
CAL1
should be as close as possible to the highest
value you will be using.
PM4COMAN-2.2-1
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