An expected value between 600-1,000 is considered normal for both sample and reference material. If the cell is dirty, or water and air are mixed in the cell, the value of sample may get lower to 100 or 200, and this case is not normal.

The ENO-30 lamp can be tested by

5-3. Detector Readings
The display can also show the current readings from the detector, such as Absorbance. Press the Arrow and Enter keys and the same time to display the Absorbance value. Remember, the “absorbance” is calculated by using the difference between the reference light which does not pass through the sample and the light intensity after passing through the sample. To see the individual Reference and Sample light signals press the Arrow and Enter keys again for the Sample value and one more time for the Reference value. These values are helpful for confirming if the detector is working properly.

The ENO-20 lamp can be tested by pressing "Check"