2.
Press "CAL" [22] key for a few seconds, until the ORP display [20] blinks and indicates "470".
3.
Shake the sensor smoothly so that any water drops that may be adhered to the plastic body are removed and introduce it to the
calibration solution (470 mV). Shake smoothly for a few seconds and press "CAL" [22] key. If the process has concluded
satisfactorily, a long "beep" will be listened and the controller will be calibrated and ready to operate.
ERROR MESSAGES:
If the calibration process is interrupted for whatever reason, the ORP controller will automatically leave the
calibration mode if the intervention of the user is not detected in a few seconds. In this case, "E1" indication in
display [20] will appear.
If the ORP value during the calibration process is very different from the expected one, (e.g., defective sensor,
etc.), display [20] will indicate "E2", not allowing calibration.
If the ORP measure is unstable during the calibration process, code "E3" will appear in display [20]. In addition,
the sensor calibration will not be allowed.
6.4. Maintenance of the pH/ORP sensors
1.
Ensure that the sensor membrane remains moist at all times.
2.
If the sensor is not going to be used for a long period, keep it submerged in a conservation solution at pH=4.0.
3.
To clean the sensor of possible dirt, avoid the use of abrasive materials that can scratch the sensor surface. Use an acid based
sensor-cleaning solution to clean the sensor.
4.
The pH/ORP sensors are a consumable part and will need to be replaced over a period of time.
Fig. 35
22