Why is the Pocket Colorimeter II™ flashing 0.0 or 2.2?

Document ID

Document ID TE550


Version 3.0


Status Published

Published Date

Published Date 25/01/2018
Why is the Pocket Colorimeter II™ flashing 0.0 or 2.2?
Pocket Colorimeter II™ flashing 0.0 or 2.2
Flashing 0.0 or 2.2 readings indicate that the sample is either under or over measuring range. 

Depending on which Pocket Colorimeter II™ is in use, and the range that is selected, a number other than 2.2 that is the the high end of the selected range may flash. In either case this most likely means that the sample concentration is above the upper limit of the selected range.

If the instrument flashes 0, 0.0, or 0.00 most likely the sample concentration is zero or below the detection limit of the instrument.

Things to check:
-Verify that the range selected is the correct range to use for the sample in question.
-If possible, switch the range and analyze the sample again. (Note: the different range's method may require a different sample cell and different reagent).
-At very low concentrations, any optical differences in the sample cells become significant. Try using one sample cell for both zeroing the instrument and reading the sample to minimize these optical differences.
-If that isn't possible try to measure a sample with a known concentration, such as a SpecCheck or standard.
-Verify the correct sample cell is being used.  Different chemistries and ranges will use different sample cells.
-Verify the sample cell compartment is clean and the sample cell is clean and not scratched.
-When using SpecCheck Standards, be sure to zero the instrument with the blank vial that comes in the SpecCheck set and not with water.
-When testing a parameter where the blank is darker than the sample, such as fluoride or ozone, be sure to zeroing the instrument with the darker blank and reading the lighter sample. Some SpecCheck Standards, such as for fluoride and ozone, require zeroing with one of the standard vials and reading the clear blank. This is opposite from how samples are measured, but in each case the instrument is zeroed with a dark color, and the lighter color is then read.

Contact technical support if these suggestions don't resolve the issue.