A scalding prevention method using a magnetic stirrer double-control temperature scalding prevention system

Abstract

The present application relates to a kind of magnetic stirrer double-control temperature anti-scald system and method, belong to the field of electronic devices.The system includes AC-DC switching power supply circuit, DC-DC power supply circuit, microprocessor, data acquisition circuit, liquid crystal drive circuit, photoelectric encoder input circuit, RS485 communication interface circuit, on-off signal switch input circuit, heating wire heating output control circuit, heating wire cut-off heating loop protection circuit, brushless motor control output circuit, three-phase direct-current brushless motor driving circuit and three-phase direct-current brushless motor;When the magnetic stirrer works, when the temperature of heating disc is higher than the highest temperature tM parameter setting value allowed for heating wire, stop heating signal and automatically cut off heating loop, when the temperature of heating disc is lower than the highest temperature tM parameter setting value allowed for heating wire, start heating again.The purpose is to protect heating wire from being burnt due to too high temperature, greatly prolong the life of heating wire.

Description

Technical Field

[0001] This invention belongs to the field of electronic devices and relates to a method for preventing burns using a magnetic stirrer with dual temperature control system. Background Technology

[0002] Magnetic stirrers are primarily used for stirring or simultaneously heating and stirring low-viscosity liquids or solid-liquid mixtures. Their basic principle is based on the repulsion and attraction of like poles in a magnetic field. The magnetic field drives a magnetic stir bar placed in the container to rotate in a circular motion, thus achieving the purpose of stirring the liquid. Combined with a heating and temperature control system, the sample temperature can be heated and controlled according to specific experimental requirements, maintaining the necessary temperature conditions and ensuring the liquid is mixed to the required consistency. Magnetic stirrers have two main functions: first, to ensure uniform mixing and temperature of reactants; second, to accelerate reaction rates or evaporation rates, shortening the reaction time. Therefore, they are widely used in laboratories. However, since the heating plates of magnetic stirrers are made of stainless steel, which has excellent thermal conductivity, they may remain very hot during or after heating, even after the stirrer has been turned off. If laboratory personnel do not follow the prescribed procedures, accidental skin contact with the heated surface can easily cause burns. Furthermore, when the magnetic stirrer controls the beaker temperature, there is a significant lag in the temperature transfer from the heating wire to the beaker. This can cause the heating wire to operate at a very high temperature for an extended period during the heating process, potentially leading to its burnout. Additionally, the beaker temperature sensor is typically inserted externally and exposed, making it susceptible to human error, oxidation of the insertion port, or poor contact, which can cause the sensor to malfunction.

[0003] Currently, magnetic stirrers typically use light indicators to prevent burns. When the stirrer is working, the anti-scalding LED indicator flashes or lights up completely when the heating plate temperature exceeds a certain level, indicating that the heating plate is too hot. However, after the magnetic stirrer is turned off, the anti-scalding LED indicator goes out due to power failure. If the heating plate temperature is still too high at this time, and the skin accidentally comes into contact with the heating plate, it can lead to burns.

[0004] Most current magnetic stirrers lack heating wire protection and stop working when the beaker temperature is abnormal. Some can switch to heating plate control, but this has a significant impact on the beaker temperature because they lack automatic heating plate target temperature recognition and are not dual-temperature control dual-PID systems. The objects controlling the beaker temperature and the objects controlling the heating plate temperature are completely different, with a very large difference.

[0005] Therefore, there is an urgent need for a method that allows users to continue to warn others of overheating even after the magnetic stirrer has been turned off. If the heating plate temperature is too high, the anti-scalding LED indicator will light up or flash to indicate this, and the stirrer's LCD screen will continue to display the heating plate temperature directly and flash, along with the character code "Hot." This provides a more intuitive warning that the heating plate temperature is too high and that the heated surface should not be touched by skin. The anti-scalding LED indicator and LCD screen will only be turned off once the heating plate temperature is below a safe level, allowing the magnetic stirrer to enter standby sleep mode. At this point, the heating plate temperature is below a safe level, and skin contact with the heating plate is safe.

[0006] Therefore, another method is needed to ensure that when the beaker temperature detection is abnormal, it can automatically switch to controlling the heating plate temperature to ensure that the beaker temperature continues to be accurate and constant without being affected; on the other hand, it is necessary to ensure the life of the heating wire so that it does not burn out due to excessive temperature. Summary of the Invention

[0007] In view of this, the purpose of the present invention is to provide a method for preventing burns using a magnetic stirrer dual temperature control system.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A dual-temperature control anti-scalding system for a magnetic stirrer includes an AC-DC switching power supply circuit, a DC-DC power supply circuit, a microprocessor, a data acquisition circuit, an LCD driving circuit, a photoelectric encoder input circuit, an RS485 communication interface circuit, an on / off signal switch input circuit, a heating wire heating output control circuit, a heating wire heating circuit cut-off protection circuit, a brushless motor control output circuit, a three-phase DC brushless motor drive circuit, and a three-phase DC brushless motor.

[0010] The microprocessor is electrically connected to the data acquisition circuit, the liquid crystal display driving circuit, the photoelectric encoder input circuit, the RS485 communication interface circuit, the on / off signal switch circuit, the heating wire heating output control circuit, the heating wire cutting off heating circuit protection circuit, the brushless motor control output circuit and the DC-DC power supply circuit.

[0011] The data acquisition circuit is electrically connected to the heating plate sensor and the beaker sensor, respectively.

[0012] The brushless motor control output circuit is electrically connected to the three-phase DC brushless motor drive circuit; the three-phase DC brushless motor drive circuit controls the speed of the three-phase DC brushless motor and is powered by an AC-DC switching power supply circuit.

[0013] The liquid crystal display driving circuit is electrically connected to the liquid crystal display module and is used for liquid crystal display.

[0014] The DC-DC power supply circuit is electrically connected to the AC-DC switching power supply circuit.

[0015] The heating output control circuit of the heating wire is also electrically connected to the heating wire of the heating plate;

[0016] The RS485 communication interface circuit is mainly used for data exchange between the magnetic stirrer and external devices, such as connecting to a host computer, printing data, or storing data on a USB flash drive.

[0017] The photoelectric encoder input circuit is used for the operation of the magnetic stirrer.

[0018] The system also includes a double-pole switch. One pole is connected to the heating control circuit of the heating plate. When it is on, it provides heating power to the heating wire of the heating plate. When it is off, it cuts off the heating circuit of the heating wire of the heating plate. The other pole is connected to an on / off signal switch. The on / off switch signal is connected to the external interrupt input I / O port of the microprocessor. When it is on, the microprocessor determines that the system is powered on. When it is off, the microprocessor determines that the system is powered off.

[0019] A method for preventing burns using a magnetic stirrer with dual temperature control based on the aforementioned system includes the following steps:

[0020] S11: When the magnetic stirrer is working, turn on the double-blade switch;

[0021] S12: After the double-blade switch is turned on, one blade provides power to the heating wire wound on the heating plate of the magnetic stirrer, supplying 220V AC power to the heating wire. The other blade provides an on / off signal to the microprocessor of the magnetic stirrer. Upon receiving the closed signal, the microprocessor determines that the magnetic stirrer is powered on, and the magnetic stirrer starts working. After starting by pressing the encoder, the stirring motor starts stirring, and the heating plate starts heating. If the beaker sensor is connected, the magnetic stirrer controls the beaker temperature to the target temperature. If the beaker sensor is not connected, the magnetic stirrer controls the heating plate temperature to the target temperature. When the temperature of the heating plate exceeds the upper limit of the safe temperature by 50 degrees Celsius, the anti-scalding LED lights up, indicating that the heating plate temperature is too high and should not be touched by skin. When the temperature of the heating plate is below the lower limit of the safe temperature by 45 degrees Celsius, the anti-scalding LED turns off, indicating that the heating plate temperature is safe and skin contact is permitted. When the temperature of the heating plate is between 45 and 50 degrees Celsius, it is in the insensitive zone. When the heating plate temperature rises, the anti-scalding LED turns off, and when the heating plate temperature falls, the anti-scalding LED lights up.

[0022] S13: After the magnetic stirrer has finished working, turn off the double-blade switch to shut down the machine;

[0023] S14: After the double-pole switch is turned off, one pole cuts off the power to the heating wire to prevent the heating actuator from malfunctioning and causing the heating wire to continue heating; the other pole disconnects the signal. Upon receiving the disconnect signal, the magnetic stirrer microprocessor determines that the magnetic stirrer is off, stops heating output, stops stirring output, and then continuously monitors the heating plate temperature. When the heating plate temperature exceeds the upper limit of the safe temperature by 50 degrees Celsius, the LCD continues to display the heating plate temperature and flashes, displaying the character code "Hot," and the anti-scalding LED lights up, indicating that the heating plate temperature is too high and should not be touched by skin; when the heating plate temperature falls below the lower limit of the safe temperature by 45 degrees Celsius, the LCD and anti-scalding LED turn off, indicating that the magnetic stirrer is off and the anti-scalding process is over, the magnetic stirrer stops all work, and enters standby sleep mode;

[0024] S15: Power off. This disconnects the power supply to the heating element and the input signal, putting the magnetic stirrer into standby sleep mode. In this state, skin contact with the heating plate will not result in burns.

[0025] A method for preventing burns using a magnetic stirrer with dual temperature control based on the aforementioned system includes the following steps:

[0026] S21: When the beaker temperature is normal, first control the beaker temperature using the PID control parameters of the beaker object. Once the beaker temperature is controlled to a constant temperature, automatically record the temperature of the heating plate as the target temperature for controlling the heating plate.

[0027] S22: If the beaker temperature is lower than the lower limit of the allowable beaker measurement temperature Lt or higher than the upper limit of the allowable beaker measurement temperature Ht within three sampling cycles, it is determined that the beaker temperature detection is abnormal and the system will automatically switch to controlling the heating plate temperature.

[0028] S23: When controlling the heating plate temperature, the PID control parameters of the heating plate object are used. The target temperature of the heating plate is the heating plate measured temperature recorded in S21. When the heating plate temperature is controlled to a constant temperature, the corresponding beaker temperature is also controlled to a constant temperature, which is the required temperature, realizing automatic temperature control switching from beaker temperature control to heating plate temperature control.

[0029] S24: When controlling the heating plate temperature, manually modify the target temperature of the heating plate to achieve any beaker temperature required for constant temperature.

[0030] S25: If the heating plate temperature exceeds the maximum allowable temperature tM parameter setting value of the heating wire, heating will stop and the heating circuit will be automatically cut off; if the heating plate temperature is lower than the maximum allowable temperature tM parameter setting value of the heating wire, heating will resume.

[0031] The beneficial effects of this invention are as follows:

[0032] (1) When the magnetic stirrer is working, if the temperature of the heating plate is too high, the anti-scalding LED will flash to remind you not to touch the heating plate to prevent burns.

[0033] (2) When the magnetic stirrer is working, if the temperature of the heating plate is higher than the maximum allowable temperature tM parameter setting value of the heating wire, the heating signal will be stopped and the heating circuit will be automatically cut off. If the temperature of the heating plate is lower than the maximum allowable temperature tM parameter setting value of the heating wire, the heating will restart. The purpose of this is to protect the heating wire from burning out due to excessive temperature and greatly extend the life of the heating wire.

[0034] (3) When the magnetic stirrer is working, if the beaker temperature sensor malfunctions, it automatically switches to controlling the heating plate temperature. By setting the heating plate's set temperature and maintaining it at a constant temperature, it effectively controls the temperature inside the beaker. The set temperature of the heating plate needs to be determined based on the required temperature of the beaker. Therefore, even if the beaker temperature sensor malfunctions, it will not affect the temperature inside the beaker.

[0035] (4) After the work is finished and the machine is turned off, if the heating plate temperature is too high, the anti-scalding LED will continue to flash and the LCD screen will continue to display the heating plate temperature too high warning. This will prevent personnel from accidentally being scalded by touching the heating plate that is too hot after the work switch is turned off.

[0036] (5) After the heating plate temperature drops to a safe temperature, the magnetic stirrer is in standby sleep mode, which is very safe and in low power consumption mode.

[0037] (6) When the magnetic stirrer is in standby sleep mode, the double-pole switch is turned off, cutting off the power supply to the heating wire of the heating plate. Therefore, it will not cause the heater actuator, such as the thyristor, to short-circuit and continue heating after shutdown.

[0038] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0039] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0040] Figure 1 This is a circuit diagram of the system of the present invention;

[0041] Figure 2 This is a software flowchart of the method of the present invention during its first power-on.

[0042] Figure 3 This is a flowchart of the software for shutting down the device by disconnecting the switch during operation, as described in the present invention.

[0043] Figure 4 This is a software flowchart of the method of the present invention for entering the working state after waking up from the standby sleep state;

[0044] Figure 5 This is a software flowchart illustrating the method of the present invention for waking up from a standby sleep state via an external interrupt;

[0045] Figure 6 This is a software flowchart of the dual temperature control system of the present invention. Detailed Implementation

[0046] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0047] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0048] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0049] (1) In a preferred embodiment of the present invention, a dual temperature control system for the BMS-09A5 magnetic stirrer is provided to prevent burns after the machine is turned off.

[0050] according to Figure 1The system includes an AC-DC switching power supply circuit, a DC-DC power supply circuit, a microprocessor, a data acquisition circuit, an LCD driving circuit, a photoelectric encoder input circuit, an RS485 communication interface circuit, an on / off signal switch input circuit, a heating wire heating output control circuit, a heating wire cutting off heating circuit protection circuit, a brushless motor control output circuit, a three-phase DC brushless motor drive circuit, and a three-phase DC brushless motor.

[0051] The microprocessor is electrically connected to the data acquisition circuit, the liquid crystal display driving circuit, the photoelectric encoder input circuit, the RS485 communication interface circuit, the on / off signal switch circuit, the heating wire heating output control circuit, the heating wire cutting off heating circuit protection circuit, the brushless motor control output circuit and the DC-DC power supply circuit.

[0052] The data acquisition circuit is electrically connected to the heating plate sensor and the beaker sensor, respectively.

[0053] The brushless motor control output circuit is electrically connected to the three-phase DC brushless motor drive circuit; the three-phase DC brushless motor drive circuit controls the speed of the three-phase DC brushless motor and is powered by an AC-DC switching power supply circuit.

[0054] The liquid crystal display driving circuit is electrically connected to the liquid crystal display module and is used for liquid crystal display.

[0055] The DC-DC power supply circuit is electrically connected to the AC-DC switching power supply circuit.

[0056] The heating output control circuit of the heating wire is also electrically connected to the heating wire of the heating plate;

[0057] The RS485 communication interface circuit is mainly used for data exchange between the magnetic stirrer and external devices, such as connecting to a host computer, printing data, or storing data on a USB flash drive.

[0058] The photoelectric encoder input circuit is used for the operation of the magnetic stirrer.

[0059] The system also includes a double-pole switch. One pole is connected to the heating control circuit of the heating plate. When it is on, it provides heating power to the heating wire of the heating plate. When it is off, it cuts off the heating circuit of the heating wire of the heating plate. The other pole is connected to an on / off signal switch. The on / off switch signal is connected to the external interrupt input I / O port of the microprocessor. When it is on, the microprocessor determines that the system is powered on. When it is off, the microprocessor determines that the system is powered off.

[0060] The system has two temperature control channels: heating plate temperature control and beaker temperature control. When the beaker temperature sensor fails, it automatically switches to control the heating plate temperature. When the beaker temperature sensor is normal, it controls the beaker temperature. The heating plate and beaker are controlled by different PID control parameters. If the temperature of the heating plate is too high, the heating circuit will be automatically cut off to prevent the heating wire of the heating plate from burning out due to excessive temperature.

[0061] The system features a three-phase DC brushless motor control to regulate the stirring speed.

[0062] The system features an LCD display, a scalding LED display, and a photoelectric encoder input circuit for display and operation. The LCD displays measured temperature, measured rotation speed, running time, parameter codes, parameter values, and a scalding indicator after shutdown; the scalding LED flashes when the heating plate temperature is too high; the photoelectric encoder input is used to start and stop the magnetic stirrer and set parameters.

[0063] The system uses a double-pole switch as the power-on and power-off switch. Closing the switch powers on the heating element and opening it powers off the system. Closing the switch connects the heating element to the power supply and the control input signal; opening the switch disconnects the heating element from the heating circuit and the control input signal.

[0064] (2) In a preferred embodiment of the present invention, a method for preventing burns when turning off the BMS-09A5 magnetic stirrer is provided.

[0065] according to Figure 2 When the magnetic stirrer is powered on for the first time, it first checks whether the magnetic stirrer switch is closed or open. If the power-on signal is off, it checks whether the heating plate temperature is below the safe temperature. If it is below the safe temperature, it enters standby sleep mode; otherwise, the anti-scalding LED flashes, and the heating plate temperature and "HOT" are displayed alternately on the LCD to indicate that the heating plate temperature is too hot. It will enter standby sleep mode again until the heating plate temperature is below the safe temperature.

[0066] according to Figure 2 When the magnetic stirrer is powered on for the first time, it first determines whether the magnetic stirrer switch is closed or open. If the power-on signal is closed, it will directly enter the working state.

[0067] according to Figure 3During operation, the magnetic stirrer continuously monitors the power on / off signal. If a power-off signal is detected, it stops running and checks if the heating plate temperature is below the safe temperature limit. If it is below the safe lower limit of 45 degrees Celsius, it directly enters standby sleep mode; otherwise, the anti-scalding LED flashes, and the LCD displays the heating plate temperature and "HOT" alternately, indicating that the heating plate temperature is overheating, until the heating plate temperature drops below the safe lower limit of 45 degrees Celsius, at which point it enters standby sleep mode. If a power-on signal is detected during operation, and the heating plate temperature is above the safe upper limit of 50 degrees Celsius, the anti-scalding LED flashes; if the heating plate temperature is below the safe lower limit of 45 degrees Celsius, the anti-scalding LED turns off. The heating plate or beaker temperature is kept constant; the stirring speed is kept constant.

[0068] according to Figure 4 , Figure 5 The magnetic stirrer is in standby sleep mode, waiting for the on / off signal to close. When the on / off signal closes, the microprocessor generates an external interrupt signal, which wakes the magnetic stirrer from standby sleep mode and puts it into working mode.

[0069] (3) In a preferred embodiment of the present invention, a method is provided for the BMS-09A5 magnetic stirrer to switch from controlling the temperature of the beaker to controlling the temperature of the heating plate.

[0070] according to Figure 5 As shown, if the beaker temperature detection of the magnetic stirrer is normal, the beaker temperature is controlled. Once the beaker temperature is constant, the detected heating plate temperature is assigned to the target temperature control of the heating plate. If the beaker temperature detection of the magnetic stirrer is abnormal, the beaker temperature control is stopped, and the heating plate temperature is automatically controlled. During the temperature control process, if the heating plate temperature exceeds the maximum allowable temperature of the heating wire, the heating signal is automatically stopped and the heating circuit of the heating wire is cut off.

[0071] Figure 6 This is a software flowchart of the dual temperature control system of the present invention.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for preventing burns using a magnetic stirrer with dual temperature control and burn prevention system, characterized in that: The system includes AC-DC converter, switching power supply circuit, DC-DC power supply circuit, microprocessor, data acquisition circuit, LCD driver circuit, photoelectric encoder input circuit, RS485 communication interface circuit, on / off signal switch input circuit, heating wire heating output control circuit, heating wire cutting off heating circuit protection circuit, brushless motor control output circuit, three-phase DC brushless motor drive circuit and three-phase DC brushless motor; The microprocessor is electrically connected to the data acquisition circuit, the liquid crystal display driving circuit, the photoelectric encoder input circuit, the RS485 communication interface circuit, the on / off signal switch circuit, the heating wire heating output control circuit, the heating wire cutting off heating circuit protection circuit, the brushless motor control output circuit and the DC-DC power supply circuit. The data acquisition circuit is electrically connected to the heating plate sensor and the beaker sensor, respectively. The brushless motor control output circuit is electrically connected to the three-phase DC brushless motor drive circuit; the three-phase DC brushless motor drive circuit controls the speed of the three-phase DC brushless motor and is powered by an AC-DC switching power supply circuit. The liquid crystal display driving circuit is electrically connected to the liquid crystal display module and is used for liquid crystal display. The DC-DC power supply circuit is electrically connected to the AC-DC switching power supply circuit. The heating output control circuit of the heating wire is also electrically connected to the heating wire of the heating plate; The RS485 communication interface circuit is used for data exchange between the magnetic stirrer and external devices. The photoelectric encoder input circuit is used for the operation of the magnetic stirrer; The system also includes a double-pole switch. One pole is connected to the heating control circuit of the heating plate. When it is on, it provides heating power to the heating wire of the heating plate. When it is off, it cuts off the heating circuit of the heating wire of the heating plate. The other pole is connected to an on / off signal switch. The on / off switch signal is connected to the external interrupt input I / O port of the microprocessor. When it is on, the microprocessor determines that the system is powered on. When it is off, the microprocessor determines that the system is powered off. The method includes the following steps: S11: When the magnetic stirrer is working, turn on the double-blade switch; S12: After the double-blade switch is turned on, one blade provides power to the heating wire wound on the heating plate of the magnetic stirrer, supplying 220V AC power to the heating wire. The other blade provides an on / off signal to the microprocessor of the magnetic stirrer. Upon receiving the closed signal, the microprocessor determines that the magnetic stirrer is powered on, and the magnetic stirrer starts working. After starting by pressing the encoder, the stirring motor starts stirring, and the heating plate starts heating. If the beaker sensor is connected, the magnetic stirrer controls the beaker temperature to the target temperature. If the beaker sensor is not connected, the magnetic stirrer controls the heating plate temperature to the target temperature. When the temperature of the heating plate exceeds the upper limit of the safe temperature by 50 degrees Celsius, the anti-scalding LED lights up, indicating that the heating plate temperature is too high and should not be touched by skin. When the temperature of the heating plate is below the lower limit of the safe temperature by 45 degrees Celsius, the anti-scalding LED turns off, indicating that the heating plate temperature is safe and skin contact is permitted. When the temperature of the heating plate is between 45 and 50 degrees Celsius, it is in the insensitive zone. When the heating plate temperature rises, the anti-scalding LED turns off, and when the heating plate temperature falls, the anti-scalding LED lights up. S13: After the magnetic stirrer has finished working, turn off the double-blade switch to shut down the machine; S14: After the double-pole switch is turned off, one pole cuts off the power to the heating wire to prevent the heating actuator from malfunctioning and causing the heating wire to continue heating; the other pole disconnects the signal. Upon receiving the disconnect signal, the magnetic stirrer microprocessor determines that the magnetic stirrer is off, stops heating output, stops stirring output, and then continuously monitors the heating plate temperature. When the heating plate temperature exceeds the upper limit of the safe temperature by 50 degrees Celsius, the LCD continues to display the heating plate temperature and flashes, displaying the character code "Hot," and the anti-scalding LED lights up, indicating that the heating plate temperature is too high and should not be touched by skin; when the heating plate temperature falls below the lower limit of the safe temperature by 45 degrees Celsius, the LCD and anti-scalding LED turn off, indicating that the magnetic stirrer is off and the anti-scalding process is over, the magnetic stirrer stops all work, and enters standby sleep mode; S15: Power off. This disconnects the power supply to the heating element and the input signal, putting the magnetic stirrer into standby sleep mode. In this state, skin contact with the heating plate will not result in burns.

2. The scalding prevention method using a magnetic stirrer dual-temperature control scalding prevention system according to claim 1, characterized in that: The method for preventing burns also includes: S21: When the beaker temperature is normal, first control the beaker temperature using the PID control parameters of the beaker object. Once the beaker temperature is controlled to a constant temperature, automatically record the temperature of the heating plate as the target temperature for controlling the heating plate. S22: If the beaker temperature is lower than the lower limit of the allowable beaker measurement temperature Lt or higher than the upper limit of the allowable beaker measurement temperature Ht within three sampling cycles, it is determined that the beaker temperature detection is abnormal and the system will automatically switch to controlling the heating plate temperature. S23: When controlling the heating plate temperature, the PID control parameters of the heating plate object are used. The target temperature of the heating plate is the heating plate measured temperature recorded in S21. When the heating plate temperature is controlled to a constant temperature, the corresponding beaker temperature is also controlled to a constant temperature, which is the required temperature, realizing automatic temperature control switching from beaker temperature control to heating plate temperature control. S24: When controlling the heating plate temperature, manually modify the target temperature of the heating plate to achieve any beaker temperature required for constant temperature. S25: If the heating plate temperature exceeds the maximum allowable temperature tM parameter setting value of the heating wire, heating will stop and the heating circuit will be automatically cut off; if the heating plate temperature is lower than the maximum allowable temperature tM parameter setting value of the heating wire, heating will resume.

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