YL Instruments YL9100 HPLC, User Manual

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YL9170 RI Detector
4-1. Adjusting the optical system
To perform the adjustment the sample and reference chamber of the flow cell have to be purged with
distilled water. When both chambers contain the same liquid theoretically the same light intensity should
reach the sample and reference side of the light sensor. In this case the optical balance should be zero.
The adjustment of the optical system is performed manually. During this procedure the position of the light
beam on the photo sensor is changed by adjusting the mirror.
During the procedure you can follow the changes by observing the change of the detector signal or more
detailed by observing the difference and sum voltage.
To adjust the optical system follow the steps listed below.
-
Switch to purge mode, make sure the red purge LED is on.
-
Flush both chambers of the flow cell with clean mobile phase for several minutes.
-
Switch back to measuring mode, make sure the red purge LED is off.
- Put the hex-wrench into one of the opened hole on the rear side.
-
Adjust the screws until the optical balance reaches a value of 0
±
20 %.
There are two adjustment screws for the mirror. Keep in mind that you might have to turn the
other screw. Anyway you should turn the screws not more that 1/2 or 3/4 turns.
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