Used scientific instruments and equipment, laboratory instruments, liquid chromatographs, gas chromatographs.

Nanjing Acon Scientific Instrument Co., Ltd. works closely with instrument brands such as Agilent, Waters, Shimadzu, Thermo, and Sciex, carefully selecting and introducing their second-hand liquid chromatographs, gas chromatographs, liquid chromatography-mass spectrometers, gas chromatography-mass spectrometers, and other analytical instruments. Although these instruments are second-hand, they all undergo strict quality testing and refurbishment processes to ensure stable performance and reliable data, meeting the stringent requirements of scientific research. The company provides comprehensive technical services, including single repairs, annual maintenance, instrument certification, and relocation services. Whether it's instrument installation and debugging, daily maintenance, or rapid response to complex malfunctions, Nanjing Acon Instrument's professional team can act quickly to ensure smooth laboratory operations. Additionally, the company offers instrument certification services to safeguard the accuracy and authority of scientific research data.

Main Performance Indicators of Analytical Instruments: Use and Maintenance of Laboratory Analytical Instruments

Abstract: After the installation of analytical instruments is completed, testing must be conducted item by item according to technical parameters. The main testing indicators for analytical instruments include accuracy, repeatability, sensitivity, response time, zero drift, and span drift. During the use of analytical instruments, to ensure accurate and reliable analysis results, it is essential to properly use, maintain, and manage these detection instruments and equipment. Below, we will introduce the knowledge of using and maintaining laboratory analytical instruments.

1. Main Performance Indicators of Analytical Instruments

The quality of measuring instruments can be reflected by indicators such as accuracy, repeatability, sensitivity, response time, zero drift, and span drift.

1. Accuracy

Also known as precision, it refers to how closely the measurement results of an instrument approach the true value. It can be expressed in terms of absolute error or relative error.

(1) Absolute error = Measured value - True value

(2) Relative error = Absolute error / True value

No instrument can measure the true value of a parameter with absolute accuracy; it can only strive to make the measured value as close as possible to the true value. In practical applications, the indication value of a high-accuracy standard instrument is used as the true value of the measured parameter, and the difference between the indication value of the measuring instrument and that of the standard instrument is the measurement error. The smaller the error value, the higher the reliability of the measuring instrument.

2. Repeatability

Refers to the percentage, relative to the maximum scale range, of the difference between each measured value and the average value when the same instrument is used to repeatedly measure a parameter under unchanged measurement conditions. This is an important indicator of the stability of instruments and meters and generally needs to be checked during commissioning and routine calibration.

3. Sensitivity

Refers to the sensitivity of the instrument's measurement. It is commonly expressed as the ratio of the change in the instrument's output to the change in the measured parameter that caused it.

4. Response Time

When the measured parameter changes, the instrument's indication of the measured value always takes some time to accurately represent it. This lag time between the change in the measured parameter and its representation is the instrument's response time. Some instruments express this using time constants (e.g., thermistor temperature measurement), while others use damping time (e.g., ammeter resistance measurement).

5. Zero Drift and Span Drift

Refers to the percentage, relative to the span, of the average change value after multiple measurements of the confirmed relative zero and maximum span of the instrument.

Use and Maintenance of Laboratory Analytical Instruments: To accurately detect various analytical data and promptly monitor each detection step, all instruments must always be in normal and完好 working condition. Even if minor or major faults occur, the cause must be identified in the shortest time possible, the malfunction排除, and normal operation restored. To achieve this, not only do professional maintenance personnel need to handle issues promptly, but users and maintenance personnel must also take measures to prevent faults from occurring.

1. Equipment Management

(1) Establish a management file for each instrument: original data, maintenance records, etc.

(2) Establish three major procedures: daily usage procedures, safety usage procedures, and daily maintenance procedures.

(3) Establish a comprehensive system of instrument responsibility and巡检 systems for large key equipment, and细化 the various专职 personnel for instruments: users must undergo pre-job theoretical and operational training and can only operate after passing exams. They must perform daily checks on the instrument's working condition. Responsible personnel must master the instrument's working principles, structure, key components, and other professional knowledge, and be responsible for formulating detection methods, daily usage management, maintenance, and instrument development.巡检 personnel must conduct instrument inspections, communicate with responsible personnel, promptly identify abnormalities and hidden dangers, and perform regular maintenance. They must possess relevant electrical and mechanical knowledge.

(4) Timely procurement of instrument spare parts and易损 spare parts.

(5) Regular instrument calibration and期间核查.

(6) Improvement and supplementation of detection instruments.

Normal instrument operation mainly encompasses the following aspects:

(1) Daily usage

(2) Daily maintenance

(3) Instrument verification and calibration

(4) Repair

Although the first three items are mainly completed by equipment users or responsible personnel, and the last item is completed by maintenance personnel, only by combining these four tasks and integrating all work and systems into the daily work of each individual can good results be achieved. Below, we further discuss these four aspects:

2. Daily Usage

In daily detection, users and instrument responsible personnel have the most contact with instruments. The working condition of the instrument is directly related to the user's operation. During instrument use, not only must operators strictly follow safety操作规程, but they must also be meticulous and careful, ensuring:

(1) Before use, carefully check whether various conditions meet requirements and whether there are any abnormalities.

(2) During use, pay attention to观察 whether the instrument's various states are good and normal, make timely adjustments as needed, and keep the instrument working in the best condition.

(3) After use, perform收尾, cleaning, or吹扫 as required, and turn off the instrument.

Only in this way can the stability, reliability, authenticity, and科学性 of detection data be ensured.

In daily use, operators may encounter some异常 conditions they are not fully familiar with. In such cases, users should not operate blindly but should promptly notify the responsible personnel or maintenance personnel to make correct judgments and handle the situation, thereby preventing faults from occurring or expanding.

3. Daily Maintenance

Instrument maintenance is divided into定期 maintenance and daily maintenance, both aimed at identifying potential faults and taking preventive measures in time to avoid malfunctions.定期 maintenance involves maintaining and servicing large key equipment at fixed intervals. This work is generally completed jointly by maintenance personnel and instrument responsible personnel. The main tasks include checking and optimizing the working condition of internal components of each instrument unit,核对 and calibrating various action parameters, checking whether易损 parts are intact, replacing defective and suspicious components, and cleaning accumulated dust inside the instrument.

Daily maintenance involves daily inspection and maintenance of instruments, including shift checks and daily巡检. Since the working requirements of each instrument differ, the check content and items for each instrument also vary. Shift operators should strictly follow the check card to carefully inspect each item of the instrument they use.

4. Instrument Verification, Calibration, and期间核查

Before an instrument is put into use, all its indicators must meet standards, which is determined through calibration. Instrument calibration has detailed procedures and requires定期 calibration. After each repair, especially of the measurement system, calibration must be performed. This work is mandatory; only after passing calibration can the instrument be used. Now, the National Accreditation Board requires the establishment of期间核查 for large analytical instruments. This work aims to check the instrument's working condition during the long calibration interval to ensure its normal operation. Responsible personnel must complete this work promptly and meticulously. If any abnormalities are found, they must be promptly addressed.

5. Repair Work

Instruments may inevitably experience some abnormal phenomena during use. If the issue is due to incorrect instrument working condition settings, the responsible personnel should promptly check and make adjustments. If it is an instrument故障, professional maintenance personnel or the instrument company's after-sales personnel should be notified as soon as possible.

During repairs, although maintenance personnel perform the operations, the cooperation of responsible personnel is still needed to jointly explore whether "habitual违规 operations" in daily use led to the fault.

Nanjing Acon Scientific Instrument Co., Ltd., with its professional attitude and优质 services, helps your scientific research reach new heights. Whether you need high-quality second-hand analytical instruments or professional technical services, we are your trusted choice. Let us work together to create new辉煌 in scientific research!