WZZ- 3AUTOMATIC POLARIMETER
OPERATING INSTRUCTION
Please read through these operrating instructions before using
CONTENTS
I.
INTRODUCTION……………………………………………… 1
II.
SPECIFICATIONS………………………………………………1
III.
PRINCIPLE AND STRUCTURE……………………………… 2
IV.
OPERATION…………………………………………………… 2
V.
MAINTENANCE……………………………………………… 4
VI.
COMMON BREAKDOWN AND HANDING………………… 5
I.
INTRODUCTION
The polarimeter is an instrument used for determining the Optical Rotation of substances.In this
way,the concentration,content ,purity,ect of certain substances can be found out.Therefore,the
polarimeter has become one of the most useful instruments in laboratories of sugar
industry,pharmaceutical industry,oil refining,foodstuff industry,chemical industry,universities and
scientific research field.
II.
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SPECIFCATIONS
Principle: digital polarimeter based on Optical Null Principle
Modulator:Faraday magneto-optical modulator
Light source: monochromater sodium lamp,wavelength 589.44nm
Minimum sample transmittance: 1%
Range of measurement: ±45º (±120ºZ)
Minimum value in reading: 0.001º(0.001ºZ)
Accuracy: ±(0.01º+measuring value×0.05%)
±(0.03ºZ+measuring value×0.05%Z)
Repeatability:sample transmittance>1% ≤0.002º(0.02ºZ)
Available minimum sample transmittance: 10%
RS232 interface
Sample tube:100mm,200mm
Power supply:220V±22V,50Hz±1Hz
Dimensions:600mm×320mm×220mm
Weight(net):30kg
1.Incandescence Lamp
5.Modulator
9.Lens
13.Auto H.V
17.Non-Linear control
21.Coder
2.Condenser
6.Collimator
3.Lens
7.Sample Tube
10.Filter
11.Aperture
14.Pre-AMP
15.FREQ-Selection
18.Speed-Feedback
19.Servo Motor
22.Display
Fig.1 Block Diagram
4.Polarizer
8.Analyzer
12.Detector
16.Power-AMP
20.Drive Gear
III.
PRINCIPLE AND STRUCTURE
Monochromatic rays(wavelength 589.44nm)from the Incandescence lamp plus interfered filter travel
successively through the condenser,lens,polarizer,modulator,collimator and then change into a
plane-polarized light.The plane of polarization is in swinging caused by the alternating current which
flows in the Faraday coil and with the frequency F.Passing through the sample tube containing
solution to be measured and the analyzer,another lens,an aperture,the light falls onto the
photomultiplier.Now the optical Signal turns into an electric signal and is magnified by the
Pre-Amplifier.
If the analyzer deviates from the Optical Zero Position(with reference to the polarizer),an alternation
optical signal with a frequency F will produce an electric signal with the same frequency F.The
electric signal processed by the Selective Frequency Amplifier and the power Amplifier drives the
servo-motor and by means of a mechanical gear it turns the analyzer until the Optical Zero Position
is regained.At the moment,the electric signal with the frequency F disappears and the servo-motor
stops running.
As soon as the polarimeter is put into operation,the analyzer will run to stop at the Optical Zero
Position.Now we should clear the display(Zero Set).If a sample with the Optical Rotation αis
placed into the sample chamber,the analyzer will deviates from the Optical Null Position by angle
α.As we stated above,the analyzer will be driven throughα angle to get a new Optical Null
Position.Theα value is displayed on a digital readout and so the Optical Rotation of the sample is
determined.
The auto H.V system serves to change the high-voltage supplied to the photomultiplier according to
the density of light fell on it and thus to meet the needs of measuring those dark-colored sample with
transmittance near than 1%.
IV.
OPERATION
i. The polarimeter should be placed in a dry place with good ventilation and kept from
corrosion.It had better been used under the temperture of 20℃.The instrument should be
handled with care and vibration is not allowed.
ii. Insert the power plug of the intrument into the 220V power source.(It is required to use an
AC electronic voltage regulation(1kVA).)And connect the grounding terminal to the earth
reliably.
iii. Turn on the power supply switch (in the left). Wait for 15-minute, turn on the Direct Current
key
iv. L C D o p e r a t e s a n d d i s p l a y . A f t e r 6 s e c o n d s , t h e L C D display ”MODE-model,C-c
oncentration,L-tube length,n-time of measurement ;Default:MODE:1,L:2.0,C:0,n:6)
v. Display model shift
a. Display model classification
MODE1-optical rotation; MODE2-specific rotation;
MODE3-concentration; MODE4-sugar degree;
b. If you need not shift display model,press “  ” button,display “0.000”.
c.
If you need shift,modify the value of “MODE,L,C,n”,After input,should press “  ”
button.When input “n”,press “  ” button，display “0.000”,this means you
can measure.When input “C”,if find input error,can press “←”,cursor can
be moved,then modify.
d. When measuring,need shift model,please press “←”.
vi. Display form
a. Measure optical rotation-MODE:1
Need input “n”
α-value of optical rotation, αAV –average value
b. Measure specific rotation-MODE:2
Need input “L(dm),C,n”
[α]-value of specific rotation,[αAV]- average value
c. Measure concentration-MODE:3
Need input “L, [α],n”
C-value of concentration,CAV-average value
d. Measure sugar degree-MODE:4
Need input “n”
Z-value of sugar degree,[Z] AV- average value
Sn-1-standard error of n=6,reflect discreteness of sample preparation and instrument
measuring result.Low discreteness,high credence of measuring result.
e. Put the test tube containing distilled water or other blank solvent into the sample
chamber,and close the cover.Press the “clear” button,display “0”.(If there are air
bubbles in the test tube,the first thing should be done is to make the air bubbles float
on the protruded tube-neck.The atomized water drops on the both ends of test tube
should be wiped dry.The screw-nut of the test tube should not be screwed down too
tightly,so as to avoid stress,otherwise,the readings may be affected.When placing the
test tube,care should be taken for the marked position and direction.)
f. Take out the test tube,then,inject the sample to be measured into the test
tube.According to the same position and direction,put the test tube into the sample
chamber,then,close the cover.Now the instrument will indicate the optical rotation of
the sample.
g. The instrument will do repetition measurement for n times automatically,and display
the value(when n=6, Sn-1 is effective).If n=1,press “repetition-measurement” button to
reset.If n>1,press “repetition-measurement” button,the instrument will measure
repeatedly for n times.
h. If the polarized angle of the sample exceeds the measuring range,the instrument will
be oscillating at ±45º,at this time,the test tube should be taken out,then the
instrument will reset to zero automatically.After diluting the sample,measure again.
i. Turn off the light source switch,power supply switch step by step when the measuring
process is over.
j. Please press “zero” button before measurement every time.
k. If the zero error<0.01º,no matter how much n is,only return to zero one time.
l. You can use RS232 cable to connect the instrument with computer.But first you
should install the supplied software.
Remark:
1. Calculate the specific rotatory power according to the formula following:
[α]=100α/LC
Where, α is the measured optical rotation;
C is the concentration of solution (g/ml);
L is the length of test tube(dm).
2. Calculate the purity of the sample according to the formula following:
Purity=Measured specific rotation/Theoretical specific rotation
3. Measurement of the international saccharic concentration
According to the international standard of saccharic concentration,it is specified to
use 26grams of pure sugar to make up 100ml of solution,to use a 200mm test
tube,and to use the sodium light to perform the measurement at 20℃.Its optical
rotation is +34.626,and its saccharic concentration is 100ºZ.
V.
MAINTENANCE
i.
ii.
iii.
VI.
Keeping
The instrument should be kept away from excess moisture,corrosive gases and violent
shock.
Correction
The instrument was calibrated before leaving our factory.If test values deviate from the
correct ones,the instrument should be regulated with our standard quartz test
tube(available to customer’s order)or with the sample whose Optical Rotation is
accurately known.If the procedure above doesn’t succeed somehow,send the instrument
back to our factory for a thorough inspection.
Replacing the Incandescence lamp(12V,35W)
For replacement,move off the ventilation louver on the left side of instrument loosen the
screw under the lamp,then the lamp can be pulled out.
COMMON BREAKDOWN AND HANDING
Breakdown Appearance
Analyses for Reason
Handling method
After turning on the power
supply switch,the lamp doesn’t
light up.
The switch is broken.
Lamp is broken.
Fuse 1.6A is broken.
Change the parts.
Or send to our repair department.
Press the “CLR” key,no display
Contact not well.
The display board is broken.
The display board is broken.
Press again.
Change.
Having display,not count.
The digital board is broken.
The photoelectric system is
broken.
Change.
Send to our repair department.
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