YSI IFL 700 IQ - Manual (Page 31)

IFL 70x IQ What to do if...
6 - 1 ba76129e01 10/2012
6 What to do if...
Mechanical damage to
the sensor
Display "----"
(no valid measured
value)
Cause Remedy
– Return the sensor
Cause Remedy
Sensor is permanently in the air Immerse the sensor in water
(see section 3.3.2)
There are too many air bubbles in
the water or on the ultrasonic trans-
ducer Select a measurement location
free of air bubbles
Sensor is dirty – Clean the sensor and/or its
environment
– Check the function of the
wiper (see section 3.5)
Thread algae floating in front of the
sensor Remove the thread algae from
the sensor or its environment
In the selected Evaluation range,
no echo is available that meets all
settings – Check whether there is a
sludge blanket in the
selected Evaluation range
– Check whether the settings
are suitable for the applica-
tion.
Defective sensor Contact the service department