Instruction manual
18
5.4 ORP -% Calibration
If controller is configured for ORP-% measuring you can perform a calibration
at two points using a low concentration sample (20%) and a high
concentration sample (80%). To calibrate the controller for ORP %:
CAL
CAL
meas
59.0
%
CAL
HOLD
SETUP
HOLD
CAL
HOLD
1. Enter Calibration mode as described in section 5.1. The display should
read “CAL ORP”.
Note: If the display reads “CAL PH”, see section 6.9 for procedures on
how to switch from pH to ORP-% readings.
2. Press the ENT key to start calibration. The display prompts you to place
the sensor in the high concentration sample (relative value of 80%).
3. Place sensor in the high concentration sample, then press the ENT key.
The electrode and CAL indicators flash. The unit automatically adjusts its
reading to match the solution value.
4. The display prompts you to place the sensor in the low concentration
sample (relative value of 20%). Remove the electrode from the first
standard, wash it well and then immerse it in the 20% standard.
5. When the display stabilizes press the ENT key. The “CAL” indicator
flashes and the controller adjusts its display to the 20% relative value and
exits to the Measurement mode.
Note: If there is a calibration error, the transmitter displays “ERR”. In
this case press the ▲ and ▼ keys simultaneously (escape) to
restart the calibration, beginning from step 1.
Note: If you stop calibration after entering the first value, or if
calibration is defective, the controller will use its original calibration
data.