Method for counting time utilization rate of gas chromatograph-mass spectrometer

Abstract

The invention discloses a method for counting the time utilization rate of a gas chromatograph-mass spectrometer, which comprises the following steps of: acquiring the working current of a gas chromatograph or a mass spectrometer or the working current of the gas chromatograph and the working current of the mass spectrometer to obtain a current spectrum, and identifying the starting and ending time of each test state through an algorithm; and the actual working time of the combination instrument is judged and the time utilization rate of the combination instrument is calculated. According to the method, the feasibility of judging the working state of the combination instrument through the working current of a single device and calculating the utilization rate of the combination instrument is verified, automatic collection of the working state of key detection equipment in a laboratory is achieved, an enterprise is helped to know the operation law and trend of the equipment, a scientific basis is provided for production plans and resource allocation of the enterprise, and the working efficiency of the laboratory is improved. The method has a remarkable application value.

Description

Technical Field

[0001] The invention belongs to the technical field of equipment working status collection and utilization rate statistics, and in particular relates to a method for counting the time utilization rate of a gas chromatograph-mass spectrometer (GCMS). Background Art

[0002] In today's rapidly developing manufacturing environment, enterprises have increasing requirements for production efficiency and management efficiency. As one of the important indicators to measure enterprise production efficiency, equipment utilization rate directly reflects the efficiency of enterprise resource utilization and production capacity. Utilization rate refers to the proportion of time that equipment takes up to create value within the time available. Traditional equipment utilization rate statistics usually rely on manual records and regular summaries. This method has many limitations, such as low efficiency, poor data accuracy, susceptibility to interference from human factors, and high labor costs.

[0003] Regarding the automatic statistical method of utilization rate, after searching, the following prior art is found:

[0004] 1. A Chinese patent application with publication number CN112784217A and invention name “Industrial Equipment Utilization Rate Statistics Method, Device, Computer Equipment and Storage Medium” discloses an industrial equipment utilization rate statistics method. The method determines the current actual operating condition of the equipment to be tested based on the acquired equipment current energy consumption data of the equipment to be tested based on a preset standard current upper limit and a standard current lower limit, and calculates the current equipment real-time utilization rate based on the determined current actual operating condition based on a preset standard processing cycle.

[0005] 2. A Chinese patent application with publication number CN104808587A and invention name "A method for calculating utilization rate statistics based on the operating status of machining equipment" also discloses a method for calculating utilization rate statistics. The method identifies the operating status of machining equipment based on a power characteristic model combined with a KNN classification algorithm, records the start and end time of each operating status, and calculates the time utilization rate and performance utilization rate of the machining equipment.

[0006] Regarding the above-mentioned prior art one, it collects device current data and determines whether the device is working through the current threshold. This method cannot cover all device situations. Some devices cannot be determined whether they are working through a simple current threshold. For example, the gas chromatograph-mass spectrometer, which is a device often involved in the field of chemical detection in the TIC industry in the present invention, has a regular characteristic curve when it is working, and some current values ​​will be in the standby current range, so the working time of the device cannot be determined by the method of the above-mentioned prior art one.

[0007] Regarding the above-mentioned prior art 2, it identifies the operating status of the processing equipment based on the power characteristic model combined with the KNN classification algorithm. It targets a single device, and the collection object is the total input power of the device. In addition, a specific power characteristic model must be trained for each different model of equipment from each manufacturer.

[0008] As for the gas chromatograph-mass spectrometer (GCMS) of the present invention, on the one hand, it is a device composed of two instruments working together, including a gas chromatograph and a mass spectrometer. On the other hand, a GCMS can flexibly configure a variety of analysis methods, covering the parameter settings of the two instruments, the gas chromatograph (GC) and the mass spectrometer (MS). Theoretically, the GCMS can be configured with thousands of test and analysis methods. Under different analysis methods, there are significant differences in key parameters such as the starting temperature of the column oven, the injection port temperature, the transmission line temperature, and the ion source temperature. Moreover, when switching the analysis method, a long waiting time is often required to allow the state of the equipment to stabilize. This brings difficulties to the application of the above-mentioned two prior art methods to calculate the GCMS utilization rate. Summary of the invention

[0009] The purpose of the present invention is to provide a method for calculating the time utilization rate of a gas chromatography-mass spectrometer.

[0010] The object of the present invention is achieved by the following technical solution: a method for counting the time utilization rate of a gas chromatograph-mass spectrometer, wherein the gas chromatograph-mass spectrometer comprises a gas chromatograph and a mass spectrometer, and wherein the method comprises the following steps:

[0011] Collect the working current of the gas chromatograph or the mass spectrometer to obtain its current spectrum, identify the start and end time of its test state through an algorithm, and use this to determine the actual working time of the combined instrument and calculate its time utilization rate. If the selected object is a mass spectrometer or it is a gas chromatograph but ends the test state before the mass spectrometer, then when determining the actual working time of the combined instrument, pay attention to correcting the actual working time of the combined instrument according to the mass spectrum acquisition time (which can be obtained by querying the instrument control software); or

[0012] The working currents of the gas chromatograph and mass spectrometer are collected to obtain their current spectra, and the start and end times of their respective test states are identified through algorithms. The actual working time of the combined instrument is jointly determined and its time utilization rate is calculated.

[0013] The experiment proved that the current information obtained from the gas chromatograph or mass spectrometer can clearly depict the state change trend of the GCMS during operation, indicating that it is effective and reliable to monitor the operating status and changes of the combined instrument through the instrument's separate current acquisition data.

[0014] In addition, after research, it was found that, generally speaking, the gas chromatograph enters the test state before the mass spectrometer, and ends the test state together with the mass spectrometer or lags behind the mass spectrometer in ending the test state. Some manufacturers' instruments can be set to end the gas chromatograph earlier than the mass spectrometer. Based on the above different situations, the test state start and end time of the gas chromatograph and mass spectrometer can be combined to determine the actual working time of the combined instrument, or the test state start and end time of the gas chromatograph or mass spectrometer can be used alone to determine. However, in this case, pay attention to introducing correction parameters to correct the results when necessary.

[0015] Generally speaking, the start and end times of their respective test states can be well identified through their respective current data, so the joint judgment method can save the need to consider the correction issue. If only the data of a single instrument is selected, since the current change of the gas chromatograph in different working states is more obvious, it is recommended to select its current spectrum for working state identification. For some test analysis methods where the current spectrum of the chromatograph does not change obviously, the current spectrum of the mass spectrometer can be used for analysis and judgment.

[0016] The present invention adopts a data acquisition module to collect the working current. In order not to damage the existing laboratory circuit structure, the data acquisition module adopted by the present invention includes a power strip, and the power output ports of the power strip are respectively connected in parallel with its power input ports through wires. The data acquisition module also includes a data collector and a plurality of (more than two) current transformers. The current transformers are connected to each parallel branch to collect the current on each parallel branch and output it to the data collector.

[0017] By adopting the data acquisition module of the present invention, it is only necessary to normally plug the gas chromatograph and the mass spectrometer into the sockets of the power strip to realize the collection of their respective working current data, which greatly reduces the cost of modifying the existing laboratory circuit for collecting the working current of the equipment, and does not need to damage the power supply lines of precision instruments such as the gas chromatograph and the mass spectrometer, which can reduce the impact on the operating status of the equipment and has strong application reliability.

[0018] The structure of the communication system on which the method of the present invention is based is as follows:

[0019] Using the Modbus RTU communication protocol, the server sends a collection instruction to the data collector at the terminal location through the LoRa communication gateway and the wireless LoRa communication module, controls the collector to collect the working current data of the gas chromatograph and the mass spectrometer respectively, and the server analyzes and processes the spectrum of the collected current data and calculates the actual working time of the combined instrument and its time utilization rate.

[0020] The above algorithm can use machine learning algorithms, such as KNN classification algorithm, CNN algorithm, etc., but it will inevitably require a large number of training samples and a long training cycle. As an improvement plan:

[0021] The present invention adopts the following algorithm to identify the start and end time of the test state of the gas chromatograph and mass spectrometer:

[0022] Step 1) According to the current trend change characteristics of the configured test analysis method, define the test start current threshold I1, the start judgment current threshold I2, the duration coefficient n, the difference judgment value D, the test end judgment current I3 and the end current threshold I4, and obtain the current acquisition frequency F and the test analysis time period T of the gas chromatograph set in the instrument control software; here I3 <I4≦I1<I2;

[0023] Step 2) Determine the time when the instrument starts working

[0024] When the working current of the instrument exceeds I1, the current time point is recorded in the cache and regarded as a pending state to determine whether it is effective;

[0025] Read the working current of a time period T. When the working current of the instrument exceeds I2 for more than three times within the period and the interval between the first reaching time and the last reaching time is greater than nT, the time point recorded above is determined to be valid and stored as the time point when the instrument starts working. Otherwise, the time point recorded in the cache is cleared.

[0026] Step 3) Determine the time point when the instrument ends working

[0027] After the instrument is judged to enter the test state, when the working current of the instrument is less than I3, the last current value collected is subtracted from the current current value. If the significant difference is greater than D, the current time point is cached and recorded, and it is regarded as a pending effective state to enter the effective determination;

[0028] Read the working current of a time period T. If the working current of the instrument is always less than I4 within the time period T, this time point is determined to be valid and stored as the time point when the instrument ends working. Otherwise, the cache record of this time point is cleared.

[0029] Beneficial effects:

[0030] 1) The present invention verifies the feasibility of judging the working status of the combined instrument and calculating its utilization rate by the working current of a single device, solves the problem of automatic collection of the working status of key laboratory testing equipment, helps enterprises understand the operating laws and trends of equipment, and provides a scientific basis for the production planning and resource allocation of enterprises, which has significant application value;

[0031] 2) The current data collection method of the present invention can realize the collection of the working current data of each instrument by simply plugging the gas chromatograph and the mass spectrometer into the socket of the power strip normally, which greatly reduces the cost of modifying the existing laboratory circuit for collecting the working current of the equipment, and does not need to damage the power supply line of precision instruments such as the gas chromatograph and the mass spectrometer, which can reduce the impact on the operating state of the equipment and has strong application reliability;

[0032] 3) For devices such as GCMS, the present invention designs a unified algorithm, which only needs to collect a round of current data of the GCMS device for a short time to analyze the current curve characteristics, and obtain several related parameters that meet the characteristics of the device and the test analysis method. Each device can call the algorithm with specific parameters passed in to determine the start and end time of the test, which not only ensures the accuracy of determining the working status of the device, but also can be quickly reused, greatly shortening the time cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Schematic diagram of the structure of the communication system based on the time utilization rate statistics method of this embodiment;

[0034] Figure 2 A schematic diagram of the structure of the data acquisition module used in this embodiment;

[0035] Figure 3 The characteristics of the current data of four different operating states of GCMS;

[0036] Figure 4 The current data of GCMS when running method A (phthalate analysis method in toy materials), the blue curve is GC, and the red curve is MS;

[0037] Figure 5 The current data of GCMS when running the test analysis method B, the blue curve is GC, and the red curve is MS;

[0038] Figure 6 The blue curve is for GC and the red curve is for MS. DETAILED DESCRIPTION

[0039] In this embodiment, the time utilization rate of the gas chromatography-mass spectrometer is calculated in the following manner:

[0040] Figure 1 This is a schematic diagram of the structure of the communication system based on the time utilization rate statistics method of this embodiment, as shown in the figure:

[0041] Using the Modbus RTU communication protocol, the server sends a collection instruction to the data collector at the terminal location through the LoRa communication gateway and the wireless LoRa communication module, and controls the collector to collect the working current data of the gas chromatograph and the mass spectrometer. Then the server analyzes and processes the collected current data and determines the working status of the gas chromatograph-mass spectrometer, especially identifying the start and end time of its test status, and finally calculates the time utilization rate of the gas chromatograph-mass spectrometer. The experiment proves that the current information of GC and MS obtained can clearly depict the state change trend of GCMS during operation, indicating that it is effective and reliable to monitor the operating status and changes of the gas chromatograph-mass spectrometer through the instrument's separate current collection data.

[0042] In order not to damage the existing laboratory circuit structure, the data acquisition module structure used in this embodiment is as follows Figure 2 As shown, it includes a power strip, which includes a shell, a power access port and two power output ports arranged on the shell, the two power output ports are respectively connected in parallel with the power input port through wires, and the data acquisition module also includes a data collector and two current transformers, the two current transformers are respectively used to collect currents on two parallel branches and output them to the data collector.

[0043] By adopting the data acquisition module of this embodiment, the GC and MS devices only need to be normally plugged into the sockets of the power strip to realize the collection of their respective working current data, which greatly reduces the cost of modifying the existing laboratory circuits for collecting the working current of the equipment, and does not need to damage the power supply lines of precision instruments such as GC and MS, which can reduce the impact on the operating status of the equipment and has strong application reliability.

[0044] Regarding the characterization of the start and end time of the gas chromatography-mass spectrometry test status:

[0045] Research has found that, generally speaking, the gas chromatograph enters the test state before the mass spectrometer, and ends the test state together with the mass spectrometer or lags behind the mass spectrometer in ending the test state. Some manufacturers' instruments can also be set to have the gas chromatograph end the test state earlier than the mass spectrometer.

[0046] That is, the start and end time of the gas chromatograph test state can usually directly represent the actual working time of the coupled instrument, unless the gas chromatograph ends the test state before the mass spectrometer. However, the start and end time of the mass spectrometer test state cannot usually directly represent the actual working time of the coupled instrument. The reason why they cannot be "directly" represented is that there is a parameter in the instrument control software: the mass spectrometer acquisition time, which reflects the actual test time of the mass spectrometer compared to the test analysis time cycle of the gas chromatograph. It can be seen that this data can be used to correct the above-mentioned situation that cannot directly reflect the actual working time of the coupled instrument, so that the start and end time monitored by them can be used. Of course, it is also possible to use the current spectra of the gas chromatograph and the mass spectrometer to identify the start and end time of the test state respectively and then obtain the union. Users can choose the best one according to the actual application scenario. For example, under normal circumstances, the changes in the current of a gas chromatograph in different working states are more obvious, so it is recommended to use its current spectrum to identify the working state. For some test analysis methods where the current spectrum of the chromatograph does not change obviously, the current spectrum of the mass spectrometer can be used for analysis and judgment. If there are no special circumstances, that is, the current spectra of both the gas chromatograph and the mass spectrometer can be used to identify the working state, and you do not want to consider the correction problem, you can use the identification results of the two to make a joint judgment.

[0047] In summary, we can determine the start and end time of the combined instrument test state by analyzing the current spectra of each of the two devices, such as through a trained KNN classification algorithm or a machine learning algorithm such as a CNN algorithm. However, according to the introduction of this type of equipment in the background technology section, a large number of training samples and a long training cycle are bound to be required.

[0048] To solve this problem, the applicant conducted the following research: the parameters that need to be loaded into the gas chromatography-mass spectrometry instrument include the initial column oven temperature, injection port temperature, flow rate, transmission line temperature, ion source temperature, etc., and its working process generally includes the following steps:

[0049] S1: Initial parameters for loading analytical methods into gas chromatograph and mass spectrometer

[0050] If the initial parameters of this analysis method are different from the parameters loaded on the instrument for the original analysis method, the chromatograph mass spectrometer will start the corresponding module to adjust the instrument to meet the new parameter loading requirements, mainly by enabling the heating and air cooling functions.

[0051] S2: After the initial parameter loading process of the instrument analysis method is completed, the gas chromatograph-mass spectrometer will enter the equipment ready state. At this time, its power value is related to its own performance and the initial parameters of the loaded analysis method, and the power fluctuates within a certain range. Then, the automatic sampler of the gas chromatograph is started, each drive motor is started, the mechanical arm starts to rotate to grab the sample bottle, and the injection needle starts to clean and absorb the sample. After the sampler injects the sample into the injection port of the gas chromatograph, the gas chromatograph and mass spectrometer receive the injection signal and start running the test method.

[0052] S3: After the analysis method is completed, the gas chromatograph will cool the column temperature and restore the flow rate to the initial state, and the filament, quadrupole, detector, etc. of the mass spectrometer will also enter the equipment ready state.

[0053] The above process usually corresponds to the initial state of loading the instrument analysis method, standby, injection, analysis, recovery to the initial state, standby and other states of the combined instrument. The current trend curves of the two instruments reflect their power characteristics and energy consumption characteristics in different states, and are finally divided into four operating states, including shutdown state, standby state, equipment ready state, and test state. Figure 3 As shown, the yellow box represents the shutdown state (being shut down or has been shut down), the blue box represents the device ready state, the orange box represents the test state, and the green box represents the standby state.

[0054] After a lot of observations and tests, it was found that the working currents of the two devices in the combined instrument have the following changing rules:

[0055] Except when turning on the device after power failure, loading the instrument analysis method, entering the test state, and executing shutdown, the current curve will fluctuate to a certain extent, and the amplitude and duration of the fluctuations will be significantly different. During the rest of the time, such as when the device is in standby or ready to go, the current will fluctuate steadily within a certain current range, and the current value will be staggered from the current value when it first enters the test state. When the device enters the test state, that is, when the analysis method is executed for testing, its current spectrum will change periodically, and the length of the cycle and the number of cycle changes are related to the settings of the instrument control software, and to be precise, they are consistent. In addition, in the test state, when the device starts and ends work, the current value will change significantly in a short period of time.

[0056] Based on the above findings, the applicant has summarized the following method to identify the starting point and end point of the gas chromatograph and mass spectrometer test status:

[0057] Step 1) According to the current trend change characteristics of each test analysis method, define the test start current threshold I1, the start judgment current threshold I2, the duration coefficient n, the difference judgment value D, the test end judgment current I3 and the end current threshold I4, and obtain the current acquisition frequency F of the device and the test analysis time period T of the SC set in the device control software; here I3 <I4≦I1<I2;

[0058] Step 2) Determine the time when the instrument starts working

[0059] When the current collected by the instrument, i.e., its working current, exceeds I1, the current time point is recorded in the cache and regarded as a pending effective state, and the determination of whether it is effective is entered;

[0060] Read the working current of a time period T. When the working current of the instrument exceeds I2 for more than three times within the period and the interval between the first reaching time and the last reaching time is greater than nT (obviously n here is less than or equal to 1), determine that the time point of the above record is valid and store it as the time point when the instrument starts working. Otherwise, clear the time point of the above cache record and determine the time point of other cache records.

[0061] Step 3) Determine the time point when the instrument ends working

[0062] After the instrument starts working, that is, enters the test state, when the working current of the instrument is less than I3, take the last current value collected minus the current current value. If the significant difference is greater than D, cache and record the current time point, regard it as a pending effective state, and enter the effective determination;

[0063] Read the working current of a time period T. If the instrument working current is always less than I4 within the time period T, this time point is determined to be valid and stored as the time point when the instrument ends working. Otherwise, the cached time point is cleared and the time points of other cached records are determined.

[0064] Taking the combined instrument running test analysis method A (phthalate analysis method in toy materials) as an example, the feasibility of the above method is verified.

[0065] Table 1 below shows the parameter settings of test analysis method A in the instrument control software.

[0066] Table 1 Parameters of test analysis method A

[0067]

[0068] Figure 4 The current data of GCMS when running the above method A, the blue curve is GC, and the red curve is MS. Figure 4The data table corresponding to the GC and MS current curves. The acquisition frequency of this experiment is once every 30 seconds, and the data in the table above only shows part of the data for one-to-one correspondence Figure 4 The horizontal axis displayed in .

[0069] like Figure 4 As shown in Table 2, the current data acquisition frequency F is 30s / time (affected by the graphic display, the time coordinate is compressed). When the GC is in the standby state, its working current basically fluctuates steadily between 0.5A and 1.5A. When the equipment is ready, its working current basically fluctuates steadily between 1.95A and 2.3A. When the GC enters the working state, its current value will rise rapidly and fluctuate in a periodic cycle. Suppose the time period required for each execution of the test analysis method is T. It can be queried from the instrument software that T = 10min (GC test cycle), so only two current thresholds need to be formulated, which are recorded as the test start current threshold I1 and the start judgment current I2. In method A, I1 is 2.5A and I2 is 5A. When the collected working current (set When the current threshold I1 of the test start current exceeds the test start current threshold I1, the current time point is recorded in the cache and set to the pending state. The working current of a time period T is read. When the GC working current exceeds the starting judgment current I2 for more than three times within the time period and the interval between the first exceeding time and the last exceeding time is greater than nT, the parameter n in method A is taken as 0.5, that is, when the GC working current exceeds the starting judgment current I2 for more than three times within the time period and the interval between the first exceeding time and the last exceeding time is greater than 0.5T, the current time point recorded this time is determined to be valid and stored as the starting working time point of the GC device. Otherwise, the time point recorded in the cache will be cleared and the time points of other cache records will be determined. In this way, the starting working time point of the GC can be determined.

[0070] After entering the test state, the program for determining the end of work will be executed. When the GC working current is less than the end determination current I3, the value in method A is 0.7A. The last current value collected is subtracted from the current current value, and the difference determination value is set to D. The value in method A is 3. When the difference is greater than the set difference determination value D, the current time point is recorded in the cache, and the time point is set to the pending state to enter the effective state to determine whether it is valid. Then read the working current of a time period T. When the GC working current is always less than the end threshold current I4 within the time period T, the value in method A is 2.5A. Then this time point is determined to be valid and stored as the end time point of the GC device. Otherwise, the cached time point will be cleared and the time points of other cached records will be determined. In this way, the end time point of the GC can be determined.

[0071] The judgment principle of MS equipment is the same as that of GC equipment.

[0072] Combined with the working mode of GCMS, it can be known that the start time of MS equipment lags behind that of GC equipment. The 2.9min in the mass spectrometer acquisition time in the parameter table of Method A in Table 1 means that when the MS equipment runs a test analysis method, it starts working at the 2.9th minute in the cycle T and ends at 10 minutes. That is, in Method A, GC and MS end their work at the same time (the test time cycle T of Method A is 10 minutes). Figure 4 In the GCMS current curve graph, it can be clearly seen that MS starts working after GC and ends working together with GC.

[0073] Table 2 GCMS time-working current data relationship table

[0074]

[0075]

[0076] This time, the working time recorded by the instrument software log information is compared with the working time determined by the method of this embodiment to verify the accuracy of the determination method of this embodiment.

[0077] The instrument software log information shows that the instrument loaded the test method at 10:27 on June 7, 2024, performed instrument tuning and status confirmation at 10:47:27 on June 7, 2024, ended at 10:50:27 on June 7, 2024, and started running the test method at 10:58:28 on June 7, 2024. It ran a total of 12 times and completed the run at 13:55:10 on June 7, 2024.

[0078] By looking at the current data and related spectra collected by the device of this embodiment, that is, Table 2 and Figure 4 , it can be clearly seen that the trend change of the current is consistent with the action status executed in the instrument log.

[0079] The collected current data is analyzed and processed using the method of this embodiment, and the determined working time period is compared with the working time points recorded in the instrument log as shown in Table 3.

[0080] Table 3 Instrument log - comparison table of the start and end time of the device determined by the method of this embodiment

[0081]

[0082]

[0083] As can be seen from the table above, the method of this embodiment can accurately identify the start and end time points of the GCMS test state regardless of whether the current data of GC or MS is used (note that the delayed test time of 2.9 min in Table 1 is added when using MS data). In addition, compared with the machine learning method, the method of this embodiment can save a lot of training time.

[0084] In order to continue to verify whether current acquisition can accurately reflect the state changes of the instrument operation method, the applicant further adopted the following test plan:

[0085] The measurement of method B was performed five times in succession using a gas chromatograph-mass spectrometer (GCMS), followed by five times in succession by the measurement of method C. During this process, the relevant current data was continuously captured and recorded.

[0086] The experimental results show that the acquired current information not only clearly depicts the state change trend of the GCMS during operation, but also accurately shows its periodic change characteristics. This result strongly proves the effectiveness and reliability of monitoring the operating status and changes of the instrument through current acquisition.

[0087] Figure 5 The blue curve is GC and the red curve is MS when running the test analysis method B. Table 4 is the parameter table of the test analysis method B.

[0088] Table 4 Parameters of test analysis method B (GC cycle T = 27 min)

[0089]

[0090]

[0091] Figure 6 The current data of GCMS when running the test analysis method C, the blue curve is GC, and the red curve is MS. Table 5 is the parameter table of the test analysis method C.

[0092] Table 5 Method C parameter table (GC cycle T = 36min)

[0093]

[0094]

[0095] Utilization rate refers to the proportion of time that equipment takes up to create value within the time available. In the field of chemical testing in the TIC industry, since each test must determine the test method to be selected based on the test requirements of the sample, different test methods will have different test cycles, and the theoretical processing cycle cannot be fixed. In addition, the TIC industry is different from the manufacturing industry, and there is no such thing as the number of unqualified products, that is, there is no way to calculate the performance utilization rate and yield rate. Therefore, the equipment utilization rate described in this invention only refers to the time utilization rate, and the formula is:

[0096]

[0097] For a gas chromatograph-mass spectrometer, its operating status includes four states: shutdown, standby, equipment ready, and test. Among them, the actual working time = the time the equipment is in the test state, and the average downtime for maintenance is 1 hour per day, that is, the planned working time per day is 23 hours (Note: the equipment does not have downtime for maintenance every day, this downtime for maintenance is obtained based on the average of the total maintenance time per month). The time utilization rate of the instrument can be calculated according to the above formula.

[0098] Regarding the above log information reading behavior, it should be stated that most brands are unwilling to open communication protocols and encrypt historical storage data on instrument software, so it is necessary to find another way to determine the start and end time of the device's working status.

[0099] GCMS is too flexible, and thousands of test analysis methods can be configured. When different test analysis methods are selected, the current curve characteristics will be different, and the equipment of different manufacturers also affects the current curve characteristics. If the method of establishing a power characteristic model or a current characteristic model is adopted, it is necessary to establish a power or current characteristic model for each different model of machine of each manufacturer, which is time-consuming and laborious, and cannot be quickly reused or expanded to GCMS equipment of other manufacturers or other models. However, the method of the present invention, for GCMS and other equipment, by designing a set of unified algorithms, only needs to collect the current data of a round of GCMS equipment in a short time to analyze the current curve characteristics, and obtain seven parameters that meet the characteristics of the equipment and the characteristics of the test analysis method, namely, the current acquisition frequency F, the test analysis method time cycle T, the test start current threshold I1, the start judgment current threshold I2, the duration coefficient n, the difference judgment value D, the test end judgment current I3, and the end current threshold I4, so that each device can call the algorithm with specific parameters passed in to determine the start and end time of the test, which not only ensures the accuracy of determining the working state of the equipment, but also can be quickly reused, greatly shortening the time cost.

Claims

1. A method for counting the time utilization rate of a gas chromatography-mass spectrometer, wherein the gas chromatography-mass spectrometer comprises a gas chromatograph and a mass spectrometer, characterized in that: The method comprises the following steps: The working current of the gas chromatograph or the mass spectrometer is collected to obtain its current spectrum, and the start and end time of its test state is identified through an algorithm, and the actual working time of the combined instrument is determined based on this and its time utilization rate is calculated. If the selected object is a mass spectrometer or it is a gas chromatograph but the test state ends before the mass spectrometer, when determining the actual working time of the combined instrument, it is important to correct the actual working time of the combined instrument according to the mass spectrum acquisition time; or The working currents of the gas chromatograph and mass spectrometer are collected to obtain their current spectra, and the start and end times of their respective test states are identified through algorithms. The actual working time of the combined instrument is jointly determined and its time utilization rate is calculated.

2. The method according to claim 1, characterized in that It uses a data acquisition module with the following structure to collect the working current. The data acquisition module includes a power strip, and the power output ports of the power strip are connected in parallel with its power input ports through wires. The data acquisition module also includes a data collector and several current transformers. The current transformers are connected to each parallel branch to collect the current on each parallel branch and output it to the data collector.

3. The method according to claim 2, characterized in that The communication system it is based on is structured as follows: Using the Modbus RTU communication protocol, the server sends a collection instruction to the data collector at the terminal location through the LoRa communication gateway and the wireless LoRa communication module, controls the collector to collect the working current data of the gas chromatograph and the mass spectrometer respectively, and the server analyzes and processes the spectrum of the collected current data and calculates the actual working time of the combined instrument and its time utilization rate.

4. The method according to any one of claims 1 to 3, characterized in that: The following algorithm is used to identify the start and end time of the gas chromatograph and mass spectrometer test status: Step 1) According to the current trend change characteristics of the configured test analysis method, define the test start current threshold I1, the start judgment current threshold I2, the duration coefficient n, the difference judgment value D, the test end judgment current I3 and the end current threshold I4, and obtain the current acquisition frequency F and the test analysis time period T of the gas chromatograph set in the instrument control software; here I3 <I4≦I1<I2; Step 2) Determine the time when the instrument starts working When the working current of the instrument exceeds I1, the current time point is recorded in the cache and regarded as a pending state to determine whether it is effective; Read the working current of a time period T. When the working current of the instrument exceeds I2 for more than three times within the period and the interval between the first reaching time and the last reaching time is greater than nT, the time point recorded above is determined to be valid and stored as the time point when the instrument starts working. Otherwise, the time point recorded in the cache is cleared. Step 3) Determine the time point when the instrument ends working After the instrument is judged to enter the test state, when the working current of the instrument is less than I3, the last current value collected is subtracted from the current current value. If the significant difference is greater than D, the current time point is cached and recorded, and it is regarded as a pending effective state to enter the effective determination; Read the working current of a time period T. If the working current of the instrument is always less than I4 within the time period T, this time point is determined to be valid and stored as the time point when the instrument ends working. Otherwise, the cache record of this time point is cleared.

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