Maintenance Schedule: Hydro EV

This document suggests a maintenance schedule for inspecting and cleaning the dispersion units and respective components. This list is a guide only; the exact frequency at which to perform tasks depends on many factors including:

• The samples being measured.
• The dispersant being used.
• The environmental conditions.

Inspect cell windows for dirt and scratches

The cell windows should be checked for general cleanliness every day, or if during a background measurement either of these is seen:

• One of the first few detectors displays a value above 100 light energy units.
• Background signal over 20 light energy units recorded by one of the detectors above detector 20.

Either of these situations would indicate a poor background; this will affect the quality of any measurements.

Check the window seals for damage

At least once a month. Always watch for signs of leaks, and rectify immediately.

Clean the covers.

Once a month.

Clean the sample flow path

Contamination by coarse particles or bubbles in the dispersant may cause fluctuations in the background. Clean the path using the cleaning function.

Clean the sample tank

If changing dispersant types, or if sample is seen to adhere to the sample tank and the normal flush routine fails to remove it.

Replace the dispersant tubing

If the tubing leaks or becomes discoloured. This may allow bubbles to enter, causing rapid fluctuations in the background.

Perform a Quality Audit Standard measurement

At least once a week or as internal quality procedures specify.