Xylem FDO 925 - Manual (Page 13)

FDO
®
925 What to do if...
29 ba75898s01 04/2010
4 What to do if...
Error symptom Cause Remedy
No temperature value or
D.O. value – No connection between meter
and D.O. sensor
– Establish connection between
meter and D.O. sensor
– Cable defective – Return the D.O. sensor
Measured value too
high or too low
or
error message,
Error – Coating on sensor cap – Clean the outside of the sensor
(see section 3.3.1)
– Membrane damaged – Exchange the sensor cap
– Service life of the sensor cap
over
– Check the sensor
– Replace the sensor cap as
necessary (see section 3.2)
– Dirt inside the sensor cap and
sensor head
– Fixing ring not properly tightened
– Sensor cap untight or defective
– Dismantle the sensor cap
– Clean the insides of the sensor
cap and sensor head (see
section 3.3.2)
– Mount the sensor cap correctly
and tighten the fixing ring as far
as it will go (see section 3.2)
– Replace a defective sensor cap
as necessary
Incorrect temperature
display – The temperature sensor is not
immersed deep enough in the
measuring solution
– Observe the minimum immersion
depth
– Temperature sensor defective – Return the D.O. sensor
Error message,
no cap – No sensor cap put on – Clean the sensor head and
sensor cap
– Sensor cap not recognized – Return the D.O. sensor
– Sensor cap defective – Replace the sensor cap