Introduction to common errors and maintenance measures of polarimeters

Introduction to common errors and maintenance measures of polarimeters Polarimeters generally work through the conversion of photoelectric signals.
It is an instrument for measuring the optical rotation of substances
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By measuring the optical rotation of the sample, the concentration, content and purity of the substance can be analyzed and determined, and it is used in the fields of food, organic chemical industry and so on
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After the polarimeter works for a long time, the change of the working state of the optical, mechanical and electrical parts causes the change of the measurement performance.
There are several obvious manifestations: ① The reading is low: the 220V AC power supply is low, which exceeds the range of the regulated power supply in the machine , the sodium lamp is dimmed
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The sodium lamp is used for a long time and the light is insufficient due to aging
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The filter is dirty, displaced, and the main optical path is not correct, which will reduce the luminous flux
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The aging sensitivity of the photomultiplier tube decreases, and the performance of electronic components weakens the output, which will cause reading errors
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②Indication is too high: the filter is displaced or damaged, the sodium lamp power supply current is too large, and the voltage is too high, which will cause a negative error in the measurement
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Excessive luminescence of sodium lamps also reduces their service life
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③ Large variation in indication and poor repeatability: improper coordination of mechanical parts, loose or displaced fasteners, and sliding of the quartz modulating sheet or modulating motor
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The photoelectric counting mechanism of the digital polarimeter is not coordinated, the performance difference between the two photocells is too large, the position of the penetration slit is not good, and so on
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The maintenance measures of the polarimeter are as follows: (1) The polarimeter should be placed in a ventilated and dry place with suitable temperature to avoid damp and mildew
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(2) The polarimeter should not be used continuously for more than 4 hours
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If it is used for a long time, it should be turned off for 10 to 15 minutes in the middle, and the sodium lamp should be cooled before continuing to use it, or blow it with an electric fan to reduce the heating degree of the lamp, so as to avoid the decrease of brightness and life
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(3) After the test tube is used, the solution should be poured out in time, washed with distilled water, dried and stored
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All lenses cannot be wiped directly by hand, but should be wiped with a soft flannel
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(4) When the polarimeter is out of use, the plastic sleeve should be put on
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When packing, it should be put into the box according to the fixed position and pressed tightly
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The above is the introduction of common errors and maintenance measures of polarimeter.
I believe that everyone has a corresponding understanding of this after reading, and everyone can use it as a reference.
I hope you can help
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