Xylem LF213T_LF213T-ID - Handbuch (Seite 16)

What to do if... LF213T
10 ba75694e02 10/2009
Outside cleaning We recommend to clean the sensor thoroughly, especially prior to measuring
low conductivity values. If necessary, unscrew the outside electrode from the
shaft.
After cleaning, thoroughly rinse with deionized water and recalibrate if
necessary.
Aging of the
conductivity
measuring cell
Normally, the conductivity measuring cell does not age. Special measuring
media (e.g. strong acids and lyes, organic solvents) or too high temperatures
shorten the operational lifetime considerably or damage the measuring cell.
The warranty does not cover cases where such conditions cause failure or
mechanical damage.
4 What to do if...
Contamination Cleaning procedure
Lime sediments Immerse in acetic acid for 5 minutes (volume
share = 10 %)
Fat/oil Clean with warm water that contains
washing-up liquid
Error symptom Cause Remedy
No temperature or
conductivity display – Connection meter - conductivity
measuring cell interrupted
– Cable defective
– Check connection meter -
conductivity measuring cell
Measurement delivers
implausible conductivity
values – Cell constant incorrectly set at the
measuring instrument
– Measuring range exceeded
– Outside electrode not completely
screwed on
– Dirt in electrode area
– Air bubbles in electrode area
– Electrodes damaged
– Check / correct the setting
– Observe the application range
– Tighten outside electrode by
hand as far as it will go
– Clean the conductivity measuring
cell (see section 3).
– Remove air bubbles by knocking
laterally
– Return the sensor
Incorrect temperature
display – The temperature sensor is not
immersed deep enough in the
measuring solution
– Temperature sensor defective
– Observe the minimum immersion
depth
– Return conductivity measuring
cell