Bio-Rad Model EM-1 Econo™ UV Monitor User Manual
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Avoid letting the flow cell become dry, as dissolved solids may pre-
cipitate and attach to the walls. This will result in baseline drift and pos-
sibly a noisy signal.
If the flow cell becomes dirty, it should be cleaned with an appropriate
solvent. (SDS, 1M HCl, 1M NaOH, ethanol, acetone, and methylene chlo-
ride will not harm Model EM-1 Econo UV Monitor flow cells.) If NaOH
is used, it should not be left in the flow cell for more than 20 minutes.
The control unit may be left on continually (power consumption is
negligible).
Section 8
Troubleshooting
Problem
Possible cause
Solution
Base line drift
Bubbles in flow cell
Clear by using pump
or
purge mode, and inter-
noisy signal
mittently pinching the
outlet tubing, holding
momentarily, and
releasing.
Insure that flow
direction is correct.
Use degassed buffers.
Lamp not warmed up
Wait 20 minutes
before use.
Filter tray is loose
Adjust fixture screws;
Flow cell is loose
these components
Case screws are loose
should be snug, not
tight.
Dirty flow cell
Clean flow cell; insure
that buffers are free of
particulate material.
Aging lamp
Replace lamp (see
Appendix B). Note:
When using the 254 nm
filter, the lamp LED will
blink before baseline
becomes noisy.
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