Xylem TB500 ONLINE TURBIDITY ANALYZERS - Manual (Page 33)

TB500 (2/07)
Rev. 1.0 29
10.0 Routine Maintenance
10.1 Cleaning the Flow Through Cuvette
Measurement cuvettes used for both grab sample and the flow through should be clean
and free of marks or scratches. Cleaning is accomplished by cleaning the interior and
exterior with a detergent solution and then rinsing several times with distilled or de-
ionized water. The cuvette can be replaced by first shutting off the flow using the provided
shutoff clamp; unscrewing the old cuvette and replacing with a fresh clean one.
10.2 Replacing or Installing the Desiccant Pouch
The TB500 continuously checks the condition of the desiccant. When the desiccant gets in
such a condition that it may cause problems, the instrument will display DESC on the
lower portion of the display to indicate the presence of humidity. See 7.14 Desiccant
Alarm.
Proper use of the supplied desiccant is essential in
maintaining the performance of the instrument. The
desiccant has been designed to have a long life; however,
replacement of the desiccant pouch will be required from
time to time.
It is essential that the enclosure seal on the instrument base
be maintained to ensure adequate desiccant life. Inspect the
seal each time the desiccant pouch is replaced. Replace or
reseat the seal if it is found to be defective.
The desiccant should be replaced when the instrument
displays DESC. A new sealed desiccant pouch and
indicator card are available from Global Water Model #
TB500-DR. To initially install or remove the old desiccant,
simply unscrew the four corner thumbscrews and remove
the electronics half of the instrument. Open the bag
protecting the new desiccant pouch and replace (or install
for a new instrument) in the desiccant tray assembly. To
speed up the recognition, by the instrument, of the new
desiccant, reset the instrument by disconnecting the sensor
interconnect cable for 2 seconds and then reconnecting it.
Note: Once the bag is opened, install the desiccant pouch immediately to prevent premature
degradation of the desiccant.
10.3 Replacing the Source Lamp
The source lamps in the TB500’s are designed for long life. The IR lamp is rated for 10
years and the white light version is rated for 7 years. If the lamp should need replacement,
we recommend calling GW Service Department for assistance.