YSI pHotoFlex STD Colorimeter - Manual (Page 66)

What to do if... pHotoFlex
®
STD
66 ba76122e01 02/2013
6.2 Photometry
Measuring range
undercut or exceeded
Obviously incorrect
measured values
Cause Remedy
– Program not suitable – Select program with suitable
measuring range
– Dilute the sample
Cause Remedy
– Measurement disturbed by
external light
– Close the external light cover.
– Cell not correctly inserted – Insert the cell so that it is
positioned on the bottom of
the cell shaft.
– Cell contaminated – Clean the cell
– Cell shaft contaminated – Clean the cell shaft
– Dilution set incorrectly – Set the dilution
– Selected program unsuitable – Select other program
– Zero measurement incorrect – Perform zero measurement
– Blank value incorrect – Remeasure the blank value