Fault Analysis and Removal of Ultraviolet Illuminometer

Symptom 1

The visible area (ultraviolet area) of the instrument does not display 100.00, but only 0.000. The reasons for this kind of failure are 1. The position of the halogen tungsten lamp (atmosphere lamp) is shifted, so that the light spot cannot enter the shooting slit correctly. 2. The position of the cutoff filter is shifted.

For the former, check the position of the visible (ultraviolet light) spot on the slit and readjust the assembly position of the halogen tungsten lamp (neon lamp) to eliminate it! The latter can be eliminated by carefully adjusting the position of the light sheet.

Symptom 2

Close the sample chamber and turn on the instrument (the reference sample is air). The instrument displays 0.000 because the rotation position (offset) of the cut-off filter group is incorrect. When it is adjusted to be equal to 550nm, it is sufficient to have half and half spots of yellow and white on the concave mirror. 

Symptom Three

When the instrument is turned on, the full wavelength does not display 100.0, but only 0.000. The reasons are 1. The grating in the monochromator falls off 2. The position of the sample slot is not correct. The former can be replaced with a grating, and the latter readjusts the optical path in the monochromator so that the light spot enters the sample chamber correctly through the exit slit, and uses a slotted filter to eliminate it by point-by-point inspection of the wavelength.

1. The boot does not work and the power indicator light is off 

Check whether the power cord plug, 2A fuse and power switch are in good condition, and replace them if damaged.

2. The data display is unstable

Make sure that the warm-up time is over 30 minutes, the power supply voltage is 220 V and there is no sudden change. If the instrument vibrates too much, it should be relocated for installation and debugging.

3. The absorbance overflows and displays E2 or ∀∀∀∀

It is a normal phenomenon that the concentration of the measured solution is too high to cause the absorbance to overflow, and it will usually disappear automatically after restarting the machine.

Check that the sample chamber is closed at the absorbance stop, otherwise the sample chamber should be closed.

4. Insufficient energy and display E

Confirm that the position of the sample groove is fixed and there is no foreign matter in it, and then observe whether the tungsten lamp is on.

Readjust the position of the tungsten lamp so that its light spot is concentrated in the middle of the slit. Confirm by observation and replacement! After the 15 V power supply board and the preamplifier circuit board are in good condition, check whether the optical filter, reflector, grating, collimator, etc. in the optical path are dirty. If the above devices are contaminated, wear special gloves for weighing and carefully clean the surface. If the mirror is moldy, it needs to be replaced. When replacing, do not touch the mirror with your hands, and do not speak to the mirror, so as not to pollute the mirror with saliva. Use the replacement method to check whether the photocell is intact. Adjust the optical path manually, and test the commonly used wavelength points one by one. Put the filter paper in the light path of the sample chamber, and detect the various monochromatic lights output by the monochromator. The monochromatic light of each wavelength should correspond correctly, and it can be zeroed after closing the sample chamber.