UNITED PRODUCTS & INSTRUMENTS INC. UNICO 1100, Руководство по обслуживанию

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Normally the UNICO 1100 Series spectrophotometer retains its wavelength calibration
indefinitely. However if the instrument receives a severe shock or is abused, use the
following methods to check wavelength calibration. Please note that this test requires the
UNICO Didymium filter, p/n 1100-110, or the Holmium Oxide filter, p/n 1100-109.
In the filter method, the didymium filter has two distinct absorbance peaks at 529nm
and 807nm. The Holmium filter has a distinct peak at 361nm. When the instrument is
calibrated properly you will find minimum Transmittance (maximum Absorbance) at the range
+2nm from these peaks. Note that the specific Transmittance values are not important as you
are only looking for the wavelength where the minimum transmittance (maximum
Absorbance) occurs.
Holmium Oxide Filter Method:
1. Turn instrument on and allow it to warm up for 15 minutes.
2. Select the Absorbance operating mode.
1. Set the wavelength to 350nm.
2. Make sure the cuvette holder is empty and place it in the sample compartment. Close
the sample compartment lid.
3. Set zero Absorbance by pressing the 0A/100%T. Wait a few seconds while the display
flashes ‘BLA’. The reading should then be 0.000A. If not, repeat step 5.
4. Remove the cuvette holder and insert the Holmium filter into it. Place it in the sample
compartment and close the lid.
5. Record the Absorbance reading on the digital display.
6. Advance the wavelength setting by 1nm and repeat steps 4 to 7.
7. Repeat step 8 until the wavelength setting reaches 370nm.
8.
Look for the maximum absorbance reading obtained, and this should be found between
359 and 363nm. The wavelength accuracy of the 1100/1100RS is + 2nm.
Didymium Filter Method:
1. Set the Wavelength to 800 nm.
2. Make sure the cuvette holder is empty and place it in the sample compartment. Close
the sample compartment lid.
3. Set zero Abs by pressing the 0A/100%T. Wait a few seconds while the display flashes
‘BLA’. The reading should then be 0.000A. If not, repeat step 3.
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