Varian ProStar 340, Operation Manual

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AUFS are provided. This switch does not affect the fixed
1V/AU output of the rear panel integrator output.
4. Wavelength Indicator: A mechanical three-digit indicator
displays operating wavelength.
5. Wavelength Selector: A mechanical continuous turn control
selects wavelengths from 190 to 800 nm. Rotating this
control clockwise decreases wavelength; counter-clockwise
rotation increases wavelength. The arrow shows the
direction of rotation to increase wavelength.
CAUTION
Do not force the wavelength control below 180 nm or over 820 nm. Damage to the
wavelength drive may result.
6. Autozero Switch: A momentary switch activates an
autozezro circuit capable of zeroing greater than 1.5 AU.
After pushing this button, the Wait Light will turn on and the
recorder output will be shunted to zero volts. Within three
seconds a new zero value will be calculated and the Wait
Light will turn off. The Over-Range Light will illuminate when
the total absorbance within the flowcell exceeds the capacity
of the circuit.
7. Over Range Light: A green LED indicates a total
absorbance in the flowcell which exceeds the autozezro
circuit capacity. The unit will continue to output voltages
proportional to absorbance upon both recorder and
integrator outputs. There will be an offset proportional to
difference of the new baseline to that of a true zero baseline.
For instance, if the autozero circuit functions to set the new
zero value to 0.002 AU, all output absorbance values will
contain an offset of 0.002.
8. Wait Indicator Light: A green LED indicates a fixed, zero volt
recorder output. This occurs when:
•
Powering up the unit. After the lamp has ignited, it is
necessary to press Switch 6 – autozero. The Wait
Indicator will then shut off and the recorder outputs will
become active.