M&C TechGroup LA 1.4 Operator's manual - Manual (Page 18)

18
Gas sampling and conditioning technology 5-5.1.1-ME
In case the read alarm LED is beaming, there is liquid on the sensor, or there is a line break, or you
must do an adjustment of the sensitivity (see chapter 14.3).
N O T E !
If the sensor is dry, the green LED indicates that the instrument is
in operating condition, the green LED is out when the red LED is on
and signalizes a liquid alarm.
14.2 FUNCTION TEST
The responsiveness of the sensors LA 1S and LA 25S should be examined before the first starting
and afterwards two times a year and is to be effected as follows:

Dismount the sensor LA 1S resp. LA 25S.

Make a short-circuit of the sensor electrodes by using a humid finger.

The electronic controller LA-1.1 resp. LA-1.4 indicates an alarm, i.e. the red LED is beaming.

After the function test, dry the electrodes with a cloth.

Remount the sensor into the receiver part.
For the sensors LA 1S and LA 25S, a parting of a cable can be simulated by disconnecting a
connection lead on the electronic controller. Also in this case, the electronic controller LA 1.1 resp.
LA1.4 must immediately indicate alarm, i.e. the red LED must beam.
N O T E !
If the alarm is not activated when executing the function test, the
sensor, the electronic controller and the connections must be
examined.
N O T E !
The sensor LA 1S is only able to detect condensate with a
conductance ration of min. 20 µS/cm.
Therefore, it is advisable to check the sensor function with the
eventually occuring condensate. For this purpose, dismount the
sensor and execute the above described function test with the
respective condensate.
W A R N I N G !
Aggressive condensate possible. Wear protective glasses and
protective clothes when dismounting, repairing or cleaning the
sensor!
14.3 ADJUSTMENT OF SENSITIVITY
At works, a standard adjustment of the electronic controllers LA-1.1 and LA-1.4 is executed for a
conducting capacity of 100µS/cm. Hereby, the length of the sensor’s connection cable does not
matter.
In case a permanent alarm is given and the red LED is permanently beaming after the initial starting in
spite of the fact that the sensor is dry, or in case the sensor is humid and no alarm is given, the
sensitivity of the sensor must be adjusted.