998-2821
Rev. D
Page 15
5. Maintenance and Warranty
The Little Dipper
2 Fluorometer is designed for light industrial monitoring applications that
require continuous measurements. It provides maximum performance and solid state reliability
with minimal maintenance.
A maintenance check should be made once per month to ensure the optical window is free from
any chemical or biological fouling. Frequency of maintenance checks are dependent on the
fouling rate of the system being monitored. Systems that have a higher fouling rate might
require more frequent maintenance checks.
5.1 Maintenance Check Using Standard Solutions
You may check if the unit is responding correctly simply by running standard solutions past
the optical window.
1) Make a standard solution (solution of known concentration of the fluorophore being
measured) that is less than the maximum concentration set for the Little Dipper
2.
2) Flow this solution past the optical window and record the mA reading
3) Calculate the solution concentration using your equation determined from Section 3.3
and compare to the actual solution concentration.
4) If the calculated concentration varies by more than 5% of the
actual solution’s
concentration, see Section 5.2 for visual inspection and cleaning.
Maintenance checks are important and will ensure the Little Dipper
2 is continuing
to provide maximum performance and measurement reliability.
5.2 Visual Inspection and Cleaning
To visually check if the optical window has been fouled:
1)
Remove the Little Dipper
2 from the mounting tee.
2)
If there is any noticeable fouling, use a soft bristle brush or non-abrasive cloth material
and soapy water to clean the optical window. Be sure to rinse thoroughly.
3)
If the fouled window is unable to be cleaned with soapy water and the soft bristle brush,
make a 10% HCL solution and use that solution, in place of the soapy water, with the
soft bristle brush to clean the window.
Note: Hydrochloric acid is a hazardous material and should only be handled by
qualified personnel.
4)
Once the optical window has been cleaned, re-install the mounting tee back onto the
Little Dipper
2.
Note: See Section 2.2 on how to properly install the mounting tee.
