Hach-Lange FILTERTRAK FT 660 sc Basic User Manual - Manual (Page 17)

Maintenance schedule
N O T I C E
The laser module and detector system are not user-servicable items. Contact
Technical Support for replacement.
Clean the instrument at least once a month. The instrument may need to
be cleaned more frequently depending on water quality.
Clean the instrument
W A R N I N G
Do not remove the bottom plate of the instrument or drain plug when
the head assembly is installed and the instrument is in operation. Risk
of exposure to Class 3B Radiation will result.
W A R N I N G
Personal injury hazard. Never remove covers from the instrument. This is a laser-
based instrument and the user risks injury if exposed to the laser.
Sediment of the size that passes through with filter effluent is difficult to
see. Reading accuracy may be affected if the instrument is not cleaned
at regular intervals. Noise (fluctuation) in the reading may indicate the
need to clean the instrument.
Refer to the illustrated steps to clean the instrument.
Make sure to remove debris from internal corners and other internal
areas that are difficult to access.
Do a calibration verification after this procedure is complete if a
calibration will not be done immediately.
Required tools and materials:
• Soft brush
• Test tube brush
• Cleaning solution (25 mL of household bleach in 3.78 L of water or
1 mL laboratory detergent (i.e., Liqui-nox) in 1L of water)
• Water that is less than 50 mNTU (0.05 NTU)
Note: Put the cleaning solution in a container that can hold all of the bubble trap.
English 17