ST217A Pharmaceutical Testing Instruments Based on Third Method of Oscillating Densitometer for Accurate Density Measurement

ST217A Pharmaceutical Testing Instruments Based on Third Method of Oscillating Densitometer for Accurate Density Measurement

The ST217A automatic drug relative density meter is designed and manufactured based on the third method of oscillating densitometer in the 2020 Chinese Pharmacopoeia 0601 relative density measurement method. The oscillating densitometer mainly consists of (usually made of glass material, used for placing samples), electromagnetic excitation system (making the oscillating tube oscillate), frequency meter (used for measuring oscillation period), and temperature control system

The principle of measuring liquid density with a U-shaped oscillating tube

The oscillation tube method is used to measure the density of substances, which uses electromagnetic waves to induce oscillations in a U-shaped glass tube. The vibration frequency of the substance is related to the density. The actual density of the substance is calculated by comparing the frequency difference between the measured substance and the reference standard substance. The oscillation tube method is used, and the measurement accuracy is high.

Performance characteristics

l Constant temperature control: As liquid density is greatly affected by temperature, it is necessary to convert the liquid density detected at real-time temperature to the liquid density at 20 ℃. This instrument adopts a constant temperature bath control, which seals the sensor, its components, and sample solution inside the constant temperature bath. The temperature of the oscillation tube (sample solution) is detected by the temperature sensor, and the electronic components are controlled by the microcontroller for cooling or heating, ensuring that the temperature inside the constant temperature bath is stable within the range of 20 ℃± 0.1 ℃. This not only solves the troubles and errors caused by conversion, but also ensures the measurement accuracy, stability, and repeatability of the instrument (constant temperature values can be customized according to user requirements)

l Directly display the density value of the liquid at 20 ℃, with temperature display: detect the oscillation frequency of the sensor through the microcontroller, use the mathematical model of the relationship between sensor frequency and liquid density to calculate the density value of the liquid, and then perform floating-point operation to ensure the accuracy of the measurement results without additional errors caused by insufficient operation bits during the operation process. The density value calculated by the microcontroller is displayed in five digits and has a temperature display window.

l Automatic sampling: Using a microcontroller to control the stepper motor to drive the peristaltic pump for sample suction, improving the automation level of the product.

l Acid and alkali resistant pipelines: The pipelines that come into direct contact with the liquid are all imported acid and alkali resistant pipelines, ensuring that the instrument can measure acid and alkali solutions.

l Data storage and transmission: Built in memory chip, capable of storing 80 sets of detection data, and can be recalled and deleted.

l Calibration function: When the instrument is not used for a long time, drift may occur. This instrument can be calibrated using 20 ℃ pure water as the standard, which is a function that glass density meters cannot achieve.

Main technical parameters

l Measurement range of density: 0.001~1.999g/cm3

l Density measurement accuracy: ± 0 001g/cm3

l Density value resolution: ± 0 001g/cm3

l Constant temperature control: 20 ℃± 0.1 ℃

l Sampling volume: 2ml/time

l Data storage: 80 sets

l Environmental temperature requirements: 5 ℃~35 ℃

l Power supply: 220V ± 22V, 50Hz ± 1 Hz, 50W

l External dimensions: 206mm x 205mm x 200mm

l Instrument weight: 3.2Kg

l Packaging size: 236 x 235 x 240mm

l Weight: 3.5kg

Packing list