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4.7 TDS Calibration
Before attempting a TDS calibration, ensure that the
smart
CHEM
-C
has been set up correctly
according to sections 4.1 to 4.6. The calibration procedure detailed below uses the sample
configurations shown in sections 4.1 to 4.6.
Automatic Temperature Compensation can be done via a temperature sensor inside the TDS sensor,
or via the separate stainless steel temperature probe. Using the TDS sensor for ATC is more
convenient, but the separate temperature probe has a faster response. If the separate temperature
probe is plugged in, the
smart
CHEM
-C
always uses this for temperature readout and ATC. To use
the TDS sensor for Temperature readout and ATC, the separate temperature sensor must be
disconnected. Please choose one or the other according to your preference.
Ensure that Temperature has been correctly calibrated (see section 7.1). A “
∗∗
” in the Temperature
readout in place of the decimal point indicates that Temperature is NOT calibrated.
1. Plug the TDS sensor into the
Cond / TDS
socket. If required, plug the separate Temperature
sensor into the
Temperature
socket.
2. Rinse the sensor(s) in distilled water. Shake off as much water as possible. Blot the outside of
the sensor(s) dry. DO NOT BLOT THE TDS ELECTRODE PLATES.
Zero Calibration
3. Let the sensor dry in air.
4. Select TDS Calibration (
→
→
F1:Calibrate
→
→
F1:TDS
).
5. The
smart
CHEM
-C
will recognise the low TDS signal and attempt a Zero calibration. For
example…
TDS 0*01ppM
ZERO
Calibration
Press Enter
6. Press
to calibrate. The Automatic Stability Function will now show a and highlight the
reading while it is unstable…
TDS
0*01
ppM
ZERO
Calibration
Waiting to Stabilise
When the TDS reading has stabilised, the unit will calibrate itself.
To calibrate immediately without waiting for complete stability, press
to disable the
Automatic Stability Function.
The “
∗
” will not be removed after a zero calibration.
Continued over the page…