Adjustments of the controller – KROHNE OPTISENS AAC 050 EN User Manual

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Manual OPTISENS AAC 050

OPTISENS AAC 050

4.4

Automatic Sensor Cleaning ASR (option)

Main menu

Basic settings

Cleaning

1 / day

Turn-on delay

6.0 h

The patented Automatic Sensor Cleaning ASR prevents staining and passivating coatings and keeps the
surface of metal sensors clean throughout the measurement.

The cleaning is an electrochemical one: in adjustable intervals the instrument applies a strong voltage to the
electrode to produce Hydrogen and Oxygen from the surrounding water. This method needs no addition of
chemicals. Both Hydrogen and Oxygen are ORP active substances that will destroy inorganic coatings such
as rust, manganese oxide, or lime, and organic coatings such as fat or grease.

Activate the cleaning after completing the set-up to conserve the clean metal surface of the new sensor
during subsequent measurements.

The cleaning process takes about 30 seconds. During this time measurement is not possible, and after
cleaning the sensor needs some time for polarisation. Therefore the display and the analog output will show
the last measured value for five minutes, and the message „cleaning in progress“ is displayed. As a safety
measure, attempts to calibrate within these five minutes are ignored.

Activation and timing
The cleaning is activated by setting the cleaning function from 0/day (never) to 1/day (every 24h) or 2/day
(every 12 h). The first cleaning starts as soon as the function is activated, and subsequent cleanings are
carried out after 24h, or 12h, according to settings.

NOTE

Often it is convenient to carry out the cleaning during the night. Therefore we have added a delay function
that enables you to set the time for the cleaning to a later hour. If, for example, you select 1 cleaning per day
at 10am and set the delay time to 12h, cleaning takes place every day at 10pm.

NOTE

The device does not contain a real-time clock. Therefore all time settings have to be repeated after power
failure or disconnection of the power supply.

NOTE

Whenever the instrument indicates „no water“, cleaning is not carried out.

Adjustments of the controller

Main menu

Set points

Selection of ON/OFF, P or PI controller, adjustment of P ranges and I
functions for 2 set points.

Basic settings

Contr. settings

Adjustment of frequencies and pulse/pause
times, hysteresis, direction of the control
action, delay