A monitoring system for a perovskite tunnel furnace heating tube

Abstract

The application provides a perovskite tunnel furnace heating pipe monitoring system, which comprises a transmitter module, a three-phase thyristor, a control module and an audible and visual alarm module; the transmitter module comprises a first Hall current transmitter, a second Hall current transmitter and a third Hall current transmitter; the control module is used for acquiring and processing a first current, a second current and a third current; the current imbalance degree is calculated according to the first current, the second current and the third current; the three-phase thyristor is controlled to be turned on or turned off and the audible and visual alarm module is controlled to enter a pre-warning mode or an alarm mode according to the current imbalance degree, so that the fault of the tunnel furnace heating pipe can be found in time, the loss of the tunnel furnace heating pipe is reduced, and the maintenance cost of the tunnel furnace heating pipe is reduced.

Description

Technical Field

[0001] This invention relates to the field of monitoring technology, and in particular to a monitoring system for heating tubes in a perovskite tunnel furnace. Background Technology

[0002] In the mass production process of perovskite solar cells, tunnel furnace annealing and crystallization is a core process that determines the phase formation quality and photoelectric conversion efficiency of the thin film. The heating tube, as a key component for the output of the thermal field within the furnace, directly affects the temperature field uniformity and process stability. Existing monitoring schemes for perovskite tunnel furnace heating tubes mostly only collect data on the overall temperature of the furnace cavity. However, the monitoring accuracy of existing perovskite tunnel furnace heating tube technologies is relatively low. Summary of the Invention

[0003] This invention provides a monitoring system for heating tubes in perovskite tunnel furnaces to reduce wear and tear on the heating tubes, lower maintenance costs, and improve monitoring accuracy.

[0004] According to one aspect of the present invention, a monitoring system for a perovskite tunnel furnace heating tube is provided, the monitoring system comprising: Transmitter module, three-phase thyristor, control module, and audible and visual alarm module; The transmitter module includes a first Hall current transmitter, a second Hall current transmitter, and a third Hall current transmitter; The first Hall current transmitter is connected to the first output terminal of the three-phase thyristor, the second Hall current transmitter is connected to the second output terminal of the three-phase thyristor, and the third Hall current transmitter is connected to the third output terminal of the three-phase thyristor; the output terminal of the three-phase thyristor is connected to the heating tube. The first Hall current transmitter, the second Hall current transmitter, the third Hall current transmitter, and the audible and visual alarm module are all connected to the control module; The first Hall current transmitter is used to acquire and convert the first current at the first output terminal of the three-phase thyristor; the second Hall current transmitter is used to acquire and convert the second current at the second output terminal of the three-phase thyristor; the second Hall current transmitter is used to acquire and convert the third current at the first output terminal of the three-phase thyristor. The control module is used for: Acquire and process the first current, the second current, and the third current; Calculate the current imbalance based on the first current, the second current, and the third current; The three-phase thyristors are turned on or off based on the current imbalance, and the audible and visual alarm module is controlled to enter either early warning or alarm mode.

[0005] Optionally, the control module is used for: When the current imbalance is less than a first preset value, the three-phase thyristor is turned on and the audible and visual alarm module is turned off. When the current imbalance is greater than or equal to the first preset value and less than the second preset value, the three-phase thyristor is turned on and the audible and visual alarm module is put into the early warning mode. When the current imbalance is greater than the second preset value, the three-phase thyristor is turned off and the audible and visual alarm module is put into alarm mode.

[0006] Optionally, the control module is used for: Determine the maximum value, minimum value, and average value of the first current, the second current, and the third current; The current imbalance is calculated based on the maximum current value, the minimum current value, and the average current value.

[0007] Optionally, the control module is used to calculate the current imbalance according to the following formula: ; ; in, This is the maximum current value. This is the minimum current value. This is the average current. For the first current, For the second current, This is the third current.

[0008] Optionally, the first Hall current transmitter, the second Hall current transmitter, the third Hall current transmitter, and the control module are all connected via double-shielded cables.

[0009] Optionally, the control module includes a filtering submodule; The filtering submodule is used to filter the first current, the second current and the third current.

[0010] Optionally, the first Hall current transmitter, the second Hall current transmitter, and the third Hall current transmitter all output a current signal of 4mA-20mA.

[0011] Optionally, the control module includes an analog-to-digital conversion submodule; The first Hall current transmitter, the second Hall current transmitter, and the third Hall current transmitter are all connected to the analog-to-digital conversion submodule; The analog-to-digital conversion submodule is used to convert the first current, the second current, and the third current from analog quantities to digital quantities.

[0012] Optionally, the monitoring system for the heating tubes of the perovskite tunnel furnace may also include: The display module is connected to the control module; The display module is used to display monitoring data in real time, wherein the monitoring data includes the first current, the second current, the third current, the current imbalance, and the mode of the audible and visual alarm module.

[0013] Optionally, the number of transmitter modules connected to the control module is less than or equal to 8.

[0014] The monitoring system for the heating tubes of a perovskite tunnel furnace according to this invention includes a transmitter module, a three-phase thyristor, a control module, and an audible and visual alarm module. The transmitter module includes a first Hall current transmitter, a second Hall current transmitter, and a third Hall current transmitter. These three Hall current transmitters can individually acquire the operating current at the three output terminals of the three-phase thyristor, facilitating subsequent judgment of the operating status of a single group of tunnel furnace heating tubes. The control module acquires and processes the first, second, and third currents; calculates the current imbalance based on the first, second, and third currents; controls the three-phase thyristor to turn on or off and controls the audible and visual alarm module to enter early warning or alarm mode based on the current imbalance. The current imbalance is an indicator of whether the three-phase current output by the three-phase thyristor is balanced. When a group of tunnel furnace heating tubes experiences aging, short circuit, or open circuit, the equivalent impedance of the heating tube changes, causing the current at the corresponding three-phase thyristor output terminal to deviate from the normal value. Therefore, the heating tube fault can be quickly located through the current imbalance. This reduces the wear and tear on the heating tubes of the tunnel furnace, lowers the maintenance costs of the heating tubes, and improves the accuracy of monitoring.

[0015] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a monitoring system for a perovskite tunnel furnace heating tube provided in an embodiment of the present invention. Detailed Implementation

[0018] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0019] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0020] This invention provides a monitoring system for heating tubes in a perovskite tunnel furnace. Figure 1 This is a schematic diagram of a monitoring system for a perovskite tunnel furnace heating tube provided in an embodiment of the present invention. (Refer to...) Figure 1 The monitoring system for the heating tubes of the perovskite tunnel furnace includes: Transmitter module 10, three-phase thyristor 20, control module 30 and audible and visual alarm module 40; Transmitter module 10 includes a first Hall current transmitter 11, a second Hall current transmitter 12 and a third Hall current transmitter 13; The first Hall current transmitter 11 is connected to the first output terminal of the three-phase thyristor 20, the second Hall current transmitter 12 is connected to the second output terminal of the three-phase thyristor 20, and the third Hall current transmitter 13 is connected to the third output terminal of the three-phase thyristor 20; the output terminal of the three-phase thyristor is connected to the heating tube. The first Hall current transmitter 11, the second Hall current transmitter 12, the third Hall current transmitter 13, and the audible and visual alarm module 40 are all connected to the control module 30. The first Hall current transmitter 11 is used to acquire and convert the first current at the first output terminal of the three-phase thyristor 20; the second Hall current transmitter 12 is used to acquire and convert the second current at the second output terminal of the three-phase thyristor 20; the second Hall current transmitter 12 is used to acquire and convert the third current at the first output terminal of the three-phase thyristor 20. Control module 30 is used for: Acquire and process the first current, the second current, and the third current; Calculate the current imbalance based on the first current, the second current, and the third current; The three-phase thyristor 20 is turned on or off based on the current imbalance, and the audible and visual alarm module 40 is controlled to enter the early warning mode or alarm mode.

[0021] Specifically, the Hall current transmitter is an integrated device that converts the current output by the three-phase thyristor 20 into a standard current signal based on the Hall effect. It features isolation, waterproofing, and high-temperature resistance. The three-phase thyristor 20 is used to regulate the power of the heating tubes in the perovskite tunnel furnace. The first Hall current transmitter 11, the second Hall current transmitter 12, and the third Hall current transmitter 13 are all fixed to the main power supply live wire at the rear end of the output terminal of the three-phase thyristor 20 in the perovskite tunnel furnace using insulating clips. A three-phase star load wiring method is used to connect the three output terminals of the three-phase thyristor 20 to a group of tunnel furnace heating tubes, with each group of tunnel furnace heating tubes having the same number and model.

[0022] The first Hall current transmitter 11 can independently acquire the first current output from the first output terminal of the three-phase thyristor and convert it into a standard industrial current signal of 4mA-20mA. The second Hall current transmitter 12 can independently acquire the second current output from the second output terminal of the three-phase thyristor and convert it into a standard industrial current signal of 4mA-20mA. The third Hall current transmitter 13 can independently acquire the third current output from the third output terminal of the three-phase thyristor and convert it into a standard industrial current signal of 4mA-20mA. The protection level of the first Hall current transmitter 11, the second Hall current transmitter 12, and the third Hall current transmitter 13 is not lower than IP65, and can avoid the high temperature of 40℃-75℃, dust, frequency conversion, and electromagnetic interference from the high-frequency start-up and shutdown of the thyristor around the perovskite tunnel furnace body, ensuring the reliability of the acquired current data. For example, the control module 30 can be a Siemens S7-200 SMART PLC.

[0023] After periodically acquiring the first, second, and third currents, the control module 30 performs filtering and analog-to-digital conversion on these currents. Based on the processed first, second, and third currents, the control module 30 determines the maximum, minimum, and average current values ​​for one cycle, and then calculates the current imbalance based on these values. The current imbalance is an indicator of whether the three-phase current output by the three-phase thyristor 20 is balanced. The control module 30 controls the three-phase thyristor 20 to turn on or off and controls the audible and visual alarm module 40 to enter warning or alarm mode based on the current imbalance. The control module 30 can monitor the output status of the three-phase thyristor 20 based on the current imbalance. When a group of tunnel furnace heating tubes experiences aging, short circuits, or open circuits, the equivalent impedance of the tunnel furnace heating tubes changes, causing the current at the corresponding three-phase thyristor 20 output to deviate from the normal value. Therefore, the current imbalance can quickly locate heating tube faults, reduce tunnel furnace heating tube losses, and lower maintenance costs.

[0024] For example, in the early warning mode, the audible and visual alarm module 40 uses a low, gentle alert tone at 200-800Hz and a slow-flashing yellow light; in the alarm mode, the audible and visual alarm module 40 uses a sharp, rapid alarm tone at 1000-3000Hz and a fast-flashing red light. The control module 30 acquires the first current, the second current, and the third current every 100ms.

[0025] The monitoring system for the heating tubes of the perovskite tunnel furnace in this embodiment of the invention includes a transmitter module 10, a three-phase thyristor 20, a control module 30, and an audible and visual alarm module 40. The transmitter module 10 includes a first Hall current transmitter 11, a second Hall current transmitter 12, and a third Hall current transmitter 13. The three Hall current transmitters can individually collect the operating current of the three output terminals of the three-phase thyristor 20, which facilitates subsequent judgment of the operating status of a single tunnel furnace heating tube. The control module 30 is used to acquire and process the first current, the second current, and the third current; calculate the current imbalance based on the first current, the second current, and the third current; control the three-phase thyristor 20 to turn on or off and control the audible and visual alarm module 40 to enter the early warning mode or the alarm mode based on the current imbalance. The current imbalance is an indicator of whether the three-phase current output by the three-phase thyristor 20 is balanced. When a group of tunnel furnace heating tubes is aged, short-circuited, or open-circuited, the equivalent impedance of the tunnel furnace heating tube will change, causing the current at the output terminal of the corresponding three-phase thyristor 20 to deviate from the normal value. Thus, the heating tube fault can be quickly located through the current imbalance, reducing the loss of the tunnel furnace heating tube, reducing the maintenance cost of the tunnel furnace heating tube, and improving the accuracy of monitoring.

[0026] Optionally, the control module 30 is used for: When the current imbalance is less than the first preset value, the three-phase thyristor 20 is turned on and the audible and visual alarm module 40 is turned off. When the current imbalance is greater than or equal to the first preset value and less than the second preset value, the three-phase thyristor 20 is turned on and the audible and visual alarm module 40 is put into the early warning mode. When the current imbalance exceeds the second preset value, the three-phase thyristor 20 is turned off and the audible and visual alarm module 40 is put into alarm mode.

[0027] Specifically, when the current imbalance is less than the first preset value, the three-phase current output by the three-phase thyristor 20 is relatively balanced, and the equivalent impedance of the tunnel furnace heating tube changes little, indicating that the tunnel furnace heating tube is operating stably. The control module 30 controls the three-phase thyristor 20 to work normally and does not activate the audible and visual alarm module 40, and the tunnel furnace heating tube operates at a constant temperature.

[0028] When the current imbalance is greater than or equal to the first preset value and less than the second preset value, the deviation of the three currents output by the three-phase thyristor 20 from the normal value is small. This indicates that there may be hidden faults such as aging of the internal resistance of a single heating tube, oxidation and loose connection of the wiring terminal, or unilateral conduction offset of the three-phase thyristor 20. The control module 30 controls the three-phase thyristor 20 to work normally and sends a warning signal to the audible and visual alarm module 40. The audible and visual alarm module 40 enters the warning mode. The audible and visual alarm module 40 uses a low and gentle prompt sound of 200 Hz-800 Hz and a yellow slow flashing light to remind the user to check the equipment. The user can use the production gap to plan the shutdown for predictive maintenance without interrupting the mass production process of the furnace.

[0029] When the current imbalance exceeds the second preset value, the three currents output by the three-phase thyristor 20 deviate significantly from their normal values, and the equivalent impedance of the tunnel furnace heating tube changes significantly, indicating that the tunnel furnace heating tube has failed. The control module 30 sends a circuit current limiting and power-off signal to the circuit power supply protection unit to control the three-phase thyristor 20 to stop working, that is, to cut off the power supply to the corresponding zone tunnel heating tube. The control module 30 sends an alarm signal to the audible and visual alarm module 40, and the audible and visual alarm module 40 enters the alarm mode. The audible and visual alarm module 40 uses a sharp and rapid alarm sound of 1000 Hz-3000 Hz and a red flashing light. At this time, the tunnel furnace heating tube is completely open-circuited, the three-phase thyristor 20 is single-phase broken down, or there is a hard electrical fault of phase-to-phase short circuit between phases, realizing independent current limiting protection for the zone without affecting the normal production of other zones.

[0030] The first preset value and the second preset value can be set according to the annealing isothermal process tolerance of different types of perovskite precursor films. For example, the first preset value can be 5% and the second preset value can be 10%.

[0031] Optionally, the control module 30 is used for: Determine the maximum, minimum, and average values ​​of the first, second, and third currents; Calculate the current imbalance based on the maximum current value, minimum current value, and average current value.

[0032] Specifically, the control module 30 calculates the average current value, using this average current value as the benchmark for imbalance judgment. This avoids judgment errors caused by overall fluctuations in the tunnel furnace's heating and cooling load. The control module 30 determines the maximum and minimum current values ​​for the current cycle based on the first, second, and third currents. Then, the control module 30 calculates the current imbalance degree based on the maximum, minimum, and average current values. The control module 30 can promptly detect abnormalities in the three-phase thyristor 20 and the tunnel furnace heating tubes based on the magnitude of the current imbalance degree, enabling timely repairs and reducing wear and tear on the tunnel furnace heating tubes, thus lowering maintenance costs.

[0033] Optionally, the control module 30 is used to calculate the current imbalance according to the following formula: ; ; in, This is the maximum current value. This is the minimum current value. This is the average current. For the first current, For the second current, This is the third current.

[0034] Specifically, the control module 30 acquires the first, second, and third currents at a fixed period, averages these currents to obtain the average current value, and uses this average current value as the imbalance judgment standard to avoid judgment errors caused by overall fluctuations in the tunnel furnace's heating and cooling load. Then, the control module 30 calculates and outputs the real-time percentage current imbalance value based on the average current value, maximum current value, and minimum current value.

[0035] Optionally, the first Hall current transmitter 11, the second Hall current transmitter 12, and the third Hall current transmitter 13 are all connected to the control module 30 via double-shielded wires.

[0036] Specifically, the use of double-shielded cables ensures that the first, second, and third currents are transmitted without signal attenuation or phase shift over a distance of 0-50m, resulting in current acquisition accuracy of less than or equal to ±0.5% and linearity ≥99.5%. It is also compatible with the current acquisition of tunnel furnace heating tubes rated at 0-100A power frequency AC purely resistive loads, ensuring the accuracy of the acquired current data and improving the stability of current transmission.

[0037] Optionally, the control module 30 includes a filtering submodule 31; The filtering submodule 31 is used to filter the first current, the second current and the third current.

[0038] Specifically, the filter submodule 31 is used to filter out the switching pulses of the three-phase thyristor 20 and the coupling noise of the workshop frequency converter in the first current, the second current and the third current, so as to ensure that the first current, the second current and the third current are effective working currents, thereby ensuring the accuracy of the current imbalance.

[0039] Optionally, the first Hall current transmitter 11, the second Hall current transmitter 12, and the third Hall current transmitter 13 all output a current signal of 4mA-20mA.

[0040] Specifically, after the first Hall current transmitter 11, the second Hall current transmitter 12, and the third Hall current transmitter 13 acquire the first current, the second current, and the third current, they first convert the first current, the second current, and the third current into voltage signals, then amplify and calibrate the voltage through the signal conditioning circuit in the Hall current transmitter, and finally convert the voltage signal into a current signal of 4mA-20mA.

[0041] Optionally, the control module 30 includes an analog-to-digital conversion submodule 32; The first Hall current transmitter 11, the second Hall current transmitter 12, and the third Hall current transmitter 13 are all connected to the analog-to-digital conversion submodule 32. The analog-to-digital conversion submodule 32 is used to convert the first current, the second current, and the third current from analog quantities to digital quantities.

[0042] Specifically, the control module 30 is used to calculate the current imbalance based on the digital values ​​of the first current, the second current, and the third current after being converted by the analog-to-digital conversion submodule 32.

[0043] Optionally, the monitoring system for the heating tubes of the perovskite tunnel furnace may also include: The display module is connected to the control module 30. The display module is used to display monitoring data in real time, including the first current, the second current, the third current, the current imbalance, and the mode of the audible and visual alarm module 40.

[0044] Specifically, the display module communicates with the control module 30 via Ethernet. Users can set first and second preset values ​​through the display module. The display module can display real-time data on the first, second, and third currents, current imbalance, and current trend graphs, as well as the warning and alarm modes of the audible and visual alarm module 40. Users can determine the trends of the first, second, and third currents based on the current trend graphs to ascertain the aging cycle of the components. The display module may include a 7-inch explosion-proof industrial HMI touchscreen.

[0045] Optionally, the number of transmitter modules 10 connected to the control module 30 is less than or equal to 8.

[0046] Specifically, the control module 30 can be adapted to the independent monitoring of the entire area of ​​a segmented, long-size mass-production perovskite tunnel furnace, calculate the current imbalance of different transmitter modules 10, and the audible and visual alarm module 40 can respond independently.

[0047] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0048] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A monitoring system for heating tubes in a perovskite tunnel furnace, characterized in that, include: Transmitter module, three-phase thyristor, control module, and audible and visual alarm module; The transmitter module includes a first Hall current transmitter, a second Hall current transmitter, and a third Hall current transmitter; The first Hall current transmitter is connected to the first output terminal of the three-phase thyristor, the second Hall current transmitter is connected to the second output terminal of the three-phase thyristor, and the third Hall current transmitter is connected to the third output terminal of the three-phase thyristor; the output terminal of the three-phase thyristor is connected to the heating tube. The first Hall current transmitter, the second Hall current transmitter, the third Hall current transmitter, and the audible and visual alarm module are all connected to the control module; The first Hall current transmitter is used to acquire and convert the first current at the first output terminal of the three-phase thyristor; the second Hall current transmitter is used to acquire and convert the second current at the second output terminal of the three-phase thyristor; the second Hall current transmitter is used to acquire and convert the third current at the first output terminal of the three-phase thyristor. The control module is used for: Acquire and process the first current, the second current, and the third current; Calculate the current imbalance based on the first current, the second current, and the third current; The three-phase thyristors are turned on or off based on the current imbalance, and the audible and visual alarm module is controlled to enter either early warning or alarm mode.

2. The monitoring system for the heating tube of the perovskite tunnel furnace according to claim 1, characterized in that: The control module is used for: When the current imbalance is less than a first preset value, the three-phase thyristor is turned on and the audible and visual alarm module is turned off. When the current imbalance is greater than or equal to the first preset value and less than the second preset value, the three-phase thyristor is turned on and the audible and visual alarm module is put into the early warning mode. When the current imbalance is greater than the second preset value, the three-phase thyristor is turned off and the audible and visual alarm module is put into alarm mode.

3. The monitoring system for the heating tube of the perovskite tunnel furnace according to claim 1, characterized in that: The control module is used for: Determine the maximum value, minimum value, and average value of the first current, the second current, and the third current; The current imbalance is calculated based on the maximum current value, the minimum current value, and the average current value.

4. The monitoring system for the heating tube of the perovskite tunnel furnace according to claim 3, characterized in that: The control module is used to calculate the current imbalance according to the following formula: ； ； in, This is the maximum current value. This is the minimum current value. This is the average current. For the first current, For the second current, This is the third current.

5. The monitoring system for the heating tube of the perovskite tunnel furnace according to claim 1, characterized in that: The first Hall current transmitter, the second Hall current transmitter, the third Hall current transmitter, and the control module are all connected by double-shielded wires.

6. The monitoring system for the heating tube of the perovskite tunnel furnace according to claim 1, characterized in that: The control module includes a filtering submodule; The filtering submodule is used to filter the first current, the second current and the third current.

7. The monitoring system for the heating tube of the perovskite tunnel furnace according to claim 1, characterized in that: The first Hall current transmitter, the second Hall current transmitter, and the third Hall current transmitter all output a current signal of 4mA-20mA.

8. The monitoring system for the heating tube of the perovskite tunnel furnace according to claim 1, characterized in that: The control module includes an analog-to-digital conversion submodule; The first Hall current transmitter, the second Hall current transmitter, and the third Hall current transmitter are all connected to the analog-to-digital conversion submodule; The analog-to-digital conversion submodule is used to convert the first current, the second current, and the third current from analog quantities to digital quantities.

9. The monitoring system for the heating tube of the perovskite tunnel furnace according to claim 1, characterized in that, Also includes: The display module is connected to the control module; The display module is used to display monitoring data in real time, wherein the monitoring data includes the first current, the second current, the third current, the current imbalance, and the mode of the audible and visual alarm module.

10. The monitoring system for the heating tube of the perovskite tunnel furnace according to claim 1, characterized in that: The number of transmitter modules connected to the control module is less than or equal to 8.

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