Contech CDP-001 User manual

DIGITAL POLARIMETER
Model CDP ‐ 001
Where innovation never stops.....
AN ISO 9001,14001 & OHSAS 18001 COMPANY

CONTENTS
1. INTRODUCTION 1
2. SPECIFICATIONS 1
3. OPERATIONS 2
a. KEYBOARD DESCRIPTION 2
b. DISPLAY DESCRIPTION 2-3
c. MEASUREMENT PARAMETERS 3
d. MEASUREMENT 4
e. MEASUREMENT CALCULATIONS 4
4. WARRANTY 5

Monochromatic rays from Infrared LED with 589.44nm wavelength travels through condenser,
lens, polarizer, modulator and collinator to form a plane polarized light. The plane of polarization
caused by the alternating current which flows through the Faraday coil at a particular frequency.
This polarized light then passes through the sample tube containing the solution to be measured
and then through the analyzer, lens, filter and an aperture before falling on the photomultiplier
detector.
The light falling on the analyzer deviates from the optical zero position (with reference to the
polarized light) to the extent of optical rotation of the sample and the photomultiplier detector
output will produce an electrical signal with the frequency corresponding to the optical rotation
of the sample. This signal after passing through the selective frequency amplifier and power
amplifier drives the servo‐motor & in turn the analyzer through a mechanical gear assembly until
the optical zero position is regained.
After switching 'ON' the polarimeter, without the sample in the compartment the analyzer will
stabilize at a position (optical zero position). When the sample with the optical rotation  is
placed in the sample compartment, the light falling on the analyzer deviates by angle  from the
optical zero position and hence the analyzer is rotated by angle  through the servo motor
coupled mechanism to get a new optical zero position. This rotation  is measured through an
encoder and is displayed on the digital readout.
The high voltage supplied to the photomultiplier tube varies in proportional to the intensity of
light falling on it and hence this instrument is able to measure dark samples with transmittance
upto 1%.
INTRODUCTION
SPECIFICATIONS
Light Source : Infrared LED.
Wave length : 589.44nm
Modulator : Faraday magneto optical modular.
Measuring range
o o
Optical Rotation : ‐45 ~ +45
o o
International Sugar Scale : ‐120 ~ +120 Z
Accuracy
o
Optical Rotation : +(0.01 + measuring value x 0.05%)
o
International Sugar Scale : +(0.03 Z+ measuring value x 0.05%Z)
Minimum transmittance of sample : 1%
Power Supply : 230V, +10% AC, 50/60 Hz
Dimensions : 600mmx320mmx240mm
Weight : 30kg
1

DISPLAY DESCRIPTION
MODE : There are 4 modes of measurement corresponding to different measuring units.
MODE 1 : Optical Rotation
MODE 2 : Specific Rotation
MODE 3 : Concentration
MODE 4: International Sugar Scale
L is the length of sample tube in decimeter. There are 2 sizes of tubes available L = 1 dm(10 cm)
& L = 2 dm(20 cm)
C is concentration of solution in gms/100ml.
N is number of measurements.
SET : For setting parameters by pressing ENTER key with display SET highlighted.
OK : OK of parameters when ENTER Key is pressed with OK highlighted
0~9 : Numeric keys for entry of all parameters
AUTO : For Automatic measurement of parameters (measurement for the number of times
automatically as per parameter N.
MANUAL : For manual measurement of the parameter
SET UP / ◄ : Setting the parameters, Stopping the test, Back entry of parameters.
ENTER : Forwarding of parameters in the entry mode, starting of test.
CLEAR : Clearing the screen.
ZERO : Zeroing the reading.
KEYBOARD DESCRIPTION
Polarimeter should be placed on a stable, vibration free surface in a dry & clean room with
o
good ventilation & temperature around 20 .
Power supply to the instrument is 230V and should be sourced through voltage stabilizer 1KVA
with a proper earthing.
Turn on the power supply switch (Allow sufficient warm up time ‐ 20 min. after and before
testing to use the instruments.)
OPERATIONS
2

Optical Rotation :
MODE : 1
L : Length of the tube in decimeters
C : 0.0000
N : Number of measurements required
Specific Rotation  :
MODE : 2
L : Length of the tube in decimeters
C : Concentration in gms/100ml
N : Number of measurements required
Concentration C
MODE : 3
L : Length of the tube in decimeters
[] : Specific Rotation
N : Number of measurements required
Sugar Scale Z
MODE 4
L : Length of the tube in decimeters
C : Concentration in gms/100ml
N : Number of measurements required
MEASUREMENT PARAMETERS
: Optical rotation of a substance
 bar : Average optical rotation
[] : Specific Rotation
[] bar: Average Specific Rotation
C : Concentration in gms/100ml
C bar : Average concentration
Z : Sugar Scale
Z bar: Average sugar scale
 : Standard deviation of parameters.
3

Keep the sample tube containing distilled water or any other blank solvent into the sample
chamber and close the cover. Press ZERO key to display reading equal to '0'.
Make sure that there are no air bubbles in the sample tube by tilting the tube to make the air
bubbles float on the protruded tube neck. The vapour drops on both the ends of sample tube
should be wiped dry. The screw nuts on both ends of the sample tube should not be tightened
too much to avoid stress on the end pieces or else the readings may get affected because of the
stress.
If there is any marking of position and direction in the tube care should be taken while placing
the tube.
Remove the sample tube, inject the solution to be measured into the tube and place it in the
chamber and close the cover. Instrument will read the optical rotation.
The instrument will repeat the measurement for N number of times automatically & all
readings are displayed along with average value and standard deviation f readings.
o o
If the optical rotation of the sample exceeds +45 the motor oscillates at +45 the sample has
to be diluted and tried again.
After the measurement, light source switch and power supply switch should be turned OFF
in the same sequence.
MEASUREMENT
MEASUREMENT CALCULATIONS
Specific Rotation [ ] = 100 x  / LC
Where  is the measured optical rotation, L is the length of the tube in dm and C is the
concentration of solution in gms/100ml.
Purity = Measured specific rotation as per instrument / theoretical specific rotation as per the
above formula.
Measurement of International sugar concentration : While 26g of pure sugar is made upto
100ml of solution by adding distilled water and a 200mm test tube is used in a polarimeter
o
using sodium light source of 589.44 nm wavelength at 20 C, the optical rotation should be
o
+34.626 and international sugar scale should be 100 Z.
4

Corporate Office: 301, Punit Indl. Premises, Turbhe Naka, Navi Mumbai - 400 705.
Tel. :[phone] / 77 / 78 / 79 / 80, 2761 8431, 3245 9901 / 02 / 06 / 18
Fax :[phone] E-mail: [email protected] / [email protected]
Website: www.contechindia.com Customer Care No. : 9322201201 / 9324201201
Email ID : [email protected]
Factory: Plot No. EL-221 TTC Indl. Area, MIDC (Electronic Zone), Mhape,
Navi Mumbai-400 701. Tel. :[phone] Fax: [phone]
service centre in Mumbai
service centre
Dealer’s Name / Branch Office Address :
5

Corporate Office : 301, Punit Indl. Premises, Turbhe, Navi Mumbai – 400 705.
Tel: [phone] (100 lines) Fax: [phone]
E‐mail : [e-mail] / [e-mail]
Website : www.contechindia.com
Customer Care No. : 9322201201 / 9324201201
Email ID : [email protected]
www.contechindia.com M/ORP/08
Where innovation never stops.....
AN ISO 9001,14001 & OHSAS 18001 COMPANY