Jenway 6305 - Manual (Page 18)

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SECTION 4 – PHOTOMETRICS MEASUREMENTS
The 6305 can perform simple measurements of % transmittance or absorbance. The sample is
measured at one wavelength and at one point in time.
4.1 TRANSMISSION MEASUREMENT MODE
To select % Transmittance use the LEFT or RIGHT arrow keys to move the cursor to the %T
indicator on the menu bar (refer to figure 2.3.1). The primary display will show the transmittance
with %T units. To adjust the wavelength use the UP and DOWN arrow keys.
The calibration must be performed at the same wavelength at which the sample will be measured.
Insert a cuvette containing the blank (clear) solution into the sample chamber and close the
instrument lid. Press the CAL key. The instrument will perform a zero % transmission calibration
followed by a 100% transmission calibration. An internal shutter is automatically activated to
perform the zero % setting and this part of the routine is therefore independent of the solution in
the light path).
Once the calibration has been performed a sample can be measured. Remove the cuvette
containing the blank solution and place a cuvette containing the sample to be measured in the
sample holder. Close the instrument lid and the % transmittance result will be shown on the
screen.
Subsequent samples can be measured in the same way. If the wavelength is adjusted between
sample measurements then the instrument must be calibrated again before more samples can be
measured.
4.2 ABSORBANCE MEASUREMENT MODE
To select absorbance use the LEFT or RIGHT arrow keys to move the cursor to the ABS indicator
on the menu bar (refer to figure 2.3.1). The primary display will show the absorbance with ABS
units. To adjust the wavelength use the UP and DOWN arrow keys.
The calibration must be performed at the same wavelength at which the sample will be measured.
Insert a cuvette containing the blank (clear) solution into the sample chamber and close the
instrument lid. Press the CAL key. The instrument will perform a zero % transmission calibration
followed by a 0.000 Absorbance calibration. An internal shutter is automatically activated to
perform the zero % setting and this part of the routine is therefore independent of the solution in
the light path.
Once the calibration has been performed a sample can be measured. Remove the cuvette
containing the blank solution and place a cuvette containing the sample to be measured in the
sample holder. Close the instrument lid and the absorbance result will be shown on the screen.
Subsequent samples can be measured in the same way. If the wavelength is adjusted between
sample measurements then the instrument must be calibrated again before more samples can be
measured.