Low sample energy on 2487/2489 detector - WKB2756

SYMPTOMS

• Sample energy is very low, but reference energy is good
• Washing the flow cell in 6N Nitric acid does not resolve issue
• Flushed unit in 100% methanol at 1 mL/min for 30 minutes but didn't resolve the problem.

ENVIRONMENT

• 2487 Dual Wavelength Absorbance Detector
• 2489 UV/Vis Detector

CAUSE

Wrong solvent like THF suspected to have been used for the testing hence causing low sample energy due to high absorbance of THF 

FIX or WORKAROUND

1.  Replace the flow cell

ADDITIONAL INFORMATION

Similar issue can also be caused by the presence of bubble in the flow cell