Remote transmission type gas density relay

Abstract

The utility model discloses a remote transmission type gas density relay, which comprises a shell, a measuring unit and a remote transmission unit, and is characterized in that the measuring unit comprises a Bourdon tube, a base and a temperature compensation element, and the temperature compensation element is connected with a trigger mechanism; the remote transmission unit comprises a temperature sensor, a pressure sensor, an intelligent processing unit and a communication module. An insulating block is arranged on the base, a slot is formed in the upper part of the insulating block for assembling the temperature sensor, and a fixing clamping piece is arranged in the slot and is used for fixing the inserted temperature sensor. According to the remote transmission type gas density relay provided by the utility model, remote transmission is realized, the slot design ensures that the environment of the temperature sensor is consistent, accurate temperature data is acquired, the fixed clamping piece enables the assembly to be stable and convenient, and the requirement of replacing the temperature sensor is met.

Description

Technical Field

[0001] This utility model relates to a gas density relay, and more particularly to a remote gas density relay. Background Technology

[0002] Gas-insulated (such as sulfur hexafluoride) electrical products have been widely used in the power sector and industrial and mining enterprises, promoting the rapid development of the power industry. Ensuring the reliable and safe operation of electrical products has become one of the important tasks of the power sector. The arc-quenching and insulating media of sulfur hexafluoride electrical products are gases; leakage is unacceptable. If leakage occurs, the reliable and safe operation of the electrical product cannot be guaranteed. Therefore, monitoring the insulating gas density value of electrical products is essential. Currently, a mechanical pointer-type gas density relay is commonly used to monitor the insulating gas density. Figure 1This density relay monitors gas density, meaning it can alarm and lock out when an electrical product leaks gas, while also displaying the local density value. This type of relay typically uses a pointer (1), a dial (2), a single temperature compensation element (3), a single Baden tube (4), a hairspring-type magnetically assisted electrical contact (5), a mechanism (6), and a base (7). When the contacts (alarm or lockout) close, the closing force relies solely on the small force of the contact hairspring; even with the added magnetic force, it remains very weak, making it extremely susceptible to vibration and resulting in unreliable contact. Most importantly, oxidation or contamination often leads to poor contact at electrical contact (5), causing serious consequences. Furthermore, the magnetically assisted electrical contact has a slow breaking speed and small contact capacity, resulting in a short lifespan. Therefore, this density relay cannot guarantee electrical performance and lifespan; once a problem occurs, the user must replace it, resulting in economic losses and failing to adequately meet requirements. Most importantly, the mechanical SF6 gas density relay currently used to monitor SF6 gas density has the following significant drawbacks: 1) When SF6 electrical products leak, an alarm signal is only issued when the gas pressure drops to the alarm value, by which time a significant amount of SF6 gas has already leaked. For example, SF6 electrical equipment with a rated pressure of 0.6 MPa commonly uses density relays with an alarm pressure of 0.52 MPa and a lockout pressure of 0.50 MPa. Many substations are now unmanned, meaning that if a leak occurs, the gas pressure drops from the rated pressure of 0.6 MPa to the alarm pressure of 0.52 MPa before the on-duty personnel notice and notify maintenance personnel to handle the leak, by which time a significant amount of SF6 gas has already leaked. Therefore, in unmanned substations, online monitoring of the density of SF6 electrical equipment is crucial for timely detection of gas leaks. 2) The contacts of this density relay generally use spiral-spring type magnetically assisted electrical contacts. When the contacts close, the closing force is very small, resulting in an unreliable contact closure. Most importantly, when subjected to oxidation or contamination, poor electrical contact often occurs, leading to failure and serious consequences. Therefore, improvement and innovation are needed to develop a remote gas density relay with good electrical performance, stable contact, and high accuracy.

[0003] To ensure the reliable operation of SF6 electrical equipment and improve the continuous and reliable operation capability of the power system, online condition detection, monitoring, and fault prediction of its performance have become important research directions in the application of SF6 electrical equipment. With the increasing demands for remote control and telemetry in unattended substations, online monitoring of the SF6 gas density, pressure, and temperature values ​​of SF6 electrical equipment has significant practical implications.

[0004] Furthermore, most current remote-type gas density relay sensors are fixed during installation, making them difficult to replace if the temperature sensor fails or is damaged. Instead, the entire gas density relay needs to be replaced or reset, resulting in high costs associated with replacing the temperature sensor in practical applications. Utility Model Content

[0005] Given that current insulating gas density relays cannot remotely transmit density values, making it difficult to monitor the SF6 gas density and temperature values ​​of SF6 electrical equipment online and to replace temperature sensors as required, this invention provides a remote-transmission gas density relay that enables remote transmission of density and temperature values ​​and allows for the installation or replacement of temperature sensors as needed.

[0006] To achieve the above objectives, the embodiments of this utility model adopt the following technical solutions:

[0007] A remote-transmission gas density relay includes a housing, within which a measurement unit and a remote-transmission unit are housed. The measurement unit includes a Baden tube, a base, a temperature compensation element, and a signal generator. One end of the Baden tube is connected to the base, and the other end is connected to the signal generator via the temperature compensation element. The remote-transmission unit includes a temperature sensor, an intelligent processing unit, and a communication module. The intelligent processing unit is connected to both the temperature sensor and the communication module and is configured to collect, process, and transmit the temperature signal acquired by the temperature sensor via the communication module. An insulating block is provided on the base, and a slot is provided on the upper part of the insulating block. A fixing clip is provided in the slot, and the temperature sensor is detachably connected to the slot via the fixing clip.

[0008] According to one aspect of the present invention, the remote transmission unit includes a printed circuit board, which is fixed on a base, and an intelligent processing unit and a communication module are disposed on the printed circuit board.

[0009] According to one aspect of the present invention, the remote transmission unit further includes a pressure sensor, which is disposed on a printed circuit board and connected to the intelligent processing unit for collecting pressure signals and transmitting them to the intelligent processing unit.

[0010] According to one aspect of the present invention, the remote transmission unit further includes a power supply module for power supply, and the power supply module is provided with a heat insulation component.

[0011] According to one aspect of this utility model, a surge protection circuit is provided on the printed circuit board.

[0012] According to one aspect of this utility model, a fault indicator light is provided on the printed circuit board.

[0013] According to one aspect of the present invention, the bottom of the insulating block is provided with an assembly hole, and the insulating block is fixedly mounted on the base by screws passing through the assembly hole.

[0014] According to one aspect of this utility model, the temperature sensor is disposed close to the temperature compensation element, and the distance between the temperature sensor and the temperature compensation element is no more than 8mm.

[0015] According to one aspect of this utility model, a shielding component is provided on the intelligent processing unit.

[0016] According to one aspect of this utility model, the communication module is a wireless WAPI communication module, a wireless LORA communication module, or a wired RS485 communication module.

[0017] According to one aspect of the present invention, the remote transmission unit further includes an amplifier circuit disposed between the temperature sensor and the intelligent processing unit.

[0018] The advantages of this invention are as follows: Long-distance transmission is achieved through the remote transmission unit, enabling online monitoring of the density, pressure, and temperature values ​​of insulating gas electrical equipment. The slot design ensures that the temperature sensor is in full contact with the surrounding environment, ensuring consistency with the environment of the temperature compensation element, thus collecting accurate temperature data and avoiding the influence of different environments. The fixing clips within the slots ensure stable and convenient assembly of the temperature sensor; installation is completed simply by insertion. The detachable fixing clips facilitate the replacement of the temperature sensor. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of a conventional pointer-type gas density relay.

[0021] Figure 2 This is a schematic diagram of the structure of the remote-transmitting gas density relay of this utility model;

[0022] Figure 3 This is a partial view of the remote-transmitting gas density relay of this utility model;

[0023] Figure 4 This is a partial view of the slot of the remote gas density relay of this utility model;

[0024] Figure 5This is a partial side view of the triggering mechanism of the remote-transmitting gas density relay of this utility model.

[0025] Figure 6 This is a schematic diagram illustrating the working principle of the remote-transmitting gas density relay of this utility model.

[0026] Figures 2-6 Reference numerals in the attached drawings: 1. Pointer; 2. Dial; 3. Temperature compensation element; 4. Baden tube; 5. Triggering mechanism; 6. Connecting rod; 7. Base; 8. Housing; 9. Connector; 101. Micro switch; 111. Signal conditioning mechanism; 1011. Contact operating handle; 13. Connecting arm; 14. Baden tube cap; 15. Terminal block; 16. Meter glass; 17. Cover; 18. Insulating block; 1801. Slot; 1802. Fixing clip; 20. Temperature sensor; 21. Pressure sensor; 22. Amplifier circuit; 23. Intelligent processing unit; 24. Power module; 25. Surge protection circuit; 26. Communication module; 27. Fault indicator light; 28. Printed circuit board; 31. Wire; 50. Movement shaft; 51. Sector-shaped curved surface gear; 510. Sector-shaped curved surface gear shaft; 511. Transmission arm; 52. Central shaft; 53. Central gear; 55. Upper clamping plate; 56. Lower clamping plate. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0028] Example 1

[0029] like Figure 2-6 As shown, a remote-transmitting gas density relay includes a housing 8, within which a measuring unit and a remote-transmitting unit are disposed. The measuring unit includes a Baden tube 4, a base 7, a temperature compensation element 3, and a signal generator. One end of the Baden tube 4 is connected to the base 7, and the other end is connected to the signal generator through the temperature compensation element 3. The remote-transmitting unit includes a temperature sensor 20, an intelligent processing unit 23, and a communication module 26. The intelligent processing unit 23 is connected to both the temperature sensor 20 and the communication module 26, and is configured to collect the temperature signal acquired by the temperature sensor 20, process it, and then transmit it through the communication module 26. An insulating block 18 is disposed on the base 7, and a slot 1801 is disposed on the upper part of the insulating block 18. A fixing clip 1802 is disposed in the slot 1801, and the temperature sensor 20 is detachably connected to the slot 1801 through the fixing clip 1802.

[0030] The insulating block 18 has a mounting hole at its bottom, and is fixedly mounted on the base 7 by screws passing through the mounting hole. The insulating block 18 is fixed to the right side of the base 7 by fasteners. The temperature sensor 20 is mounted on the base 7 via the insulating block 18 and is located below the temperature compensation element 3.

[0031] The retaining clip 1802 is detachably mounted on the slot 1801 to facilitate the replacement of the temperature sensor 20. This significantly improves the maintainability and flexibility of the temperature sensor 20, allowing operators to quickly and easily remove the retaining clip 1802 when the temperature sensor 20 needs to be replaced or repaired, without the need for a complicated disassembly process or additional tools. This significantly shortens maintenance time and reduces operational difficulty.

[0032] The temperature sensor 20 is positioned close to the temperature compensation element 3, with a distance of no more than 8 mm between them. The temperature sensor 20 extends and is fixed near the temperature compensation element 3 via an insulating block 18, allowing for accurate measurement of the temperature value of the density relay's temperature compensation element 3. This ensures that the density value monitored online and the density value displayed by the on-site pointer 1 are very close. The 8 mm distance between the temperature sensor 20 and the temperature compensation element 3 makes the temperature T1 of the temperature compensation element 3 and the temperature T2 of the temperature sensor 20 very close, ensuring that T1-T2 ≤ 1℃. This design improvement further enhances the consistency between the online monitored density value and the density value displayed by the on-site pointer 1, meeting standard requirements.

[0033] Among them, slot 1801 is a semi-open slot 1801, which ensures that the temperature sensor 20 is in full contact with the surrounding environment to be measured, and ensures that it is consistent with the environment where the temperature compensation element 3 is located, so as to collect accurate temperature data and avoid the influence of different environments.

[0034] The remote transmission unit includes a printed circuit board 28, which is fixed on the base 7. The intelligent processing unit 23 and the communication module 26 are disposed on the printed circuit board 28. The remote transmission unit also includes an amplifier circuit 22, which is connected to the temperature sensor 20 and the intelligent processing unit 23 respectively, and is configured to amplify the temperature signal collected by the temperature sensor 20 and transmit it to the intelligent processing unit 23.

[0035] The working principle or steps of the remote gas density relay are as follows: The temperature value is measured by the temperature sensor 20, and the measured temperature value signal is amplified by the amplifier circuit 22. The amplified temperature signal is collected by the intelligent processing unit 23, and the gas density value P20 is calculated by the intelligent processing unit 23. The gas density value P20 is transmitted over a long distance through the communication module 26, thereby realizing the online monitoring of the density and temperature values ​​of the gas electrical equipment.

[0036] To further improve performance, a storage unit is also included, which is connected to the intelligent processing unit 23 and integrated on the printed circuit board 28 for storing monitored data and information.

[0037] The communication module 26 can be a wireless WAPI communication module, a wireless LORA communication module, or a wired RS485 communication module. That is, the communication method of this remote gas density relay can be wireless WAPI communication, wireless LORA communication, or wired RS485 communication.

[0038] In this embodiment, three microswitches 101 are used as gas density relay signal generators. The signal generators are equipped with a transmission triggering mechanism 5. The gas density relay is also equipped with a pointer 1 and a dial 2 for displaying the indicated value.

[0039] The measuring unit is based on the Baden tube 4 and uses a temperature compensation element 3 to correct for changes in pressure and temperature, reflecting changes in gas density. Specifically, under the pressure of the gas being measured, the change in density due to the temperature compensation element 3 causes a corresponding change in pressure, forcing the end of the Baden tube 4 to undergo elastic deformation—displacement. This displacement is transmitted to the core shaft 50 of the transmission trigger mechanism 5 via the temperature compensation element 3, and then to the pointer 1, thus indicating the measured gas density value on the dial 2. One end of the Baden tube 4 is welded to the base 7, and the other end is fixed to one end of the temperature compensation element 3 via the Baden tube cap 14. The other end of the temperature compensation element 3 is connected to the starting end of the transmission trigger mechanism 5 via a connecting arm 13 and a connecting rod 6. Microswitches 101 are fixed to the base 7, and each microswitch 101 has a contact operation handle 1011. The signal adjustment mechanism 111 is paired with three microswitches 101 and mounted on the central shaft 52, which is an extension of the movement shaft 50 and integral with it. The signal adjustment mechanism 111 consists of three eccentric wheels spaced apart on the central shaft 52. The dial 2 is fixed to the base 7, and the pointer 1 is fixed to the front end of the movement shaft 50. The signal adjustment mechanism 111 drives the contact operation handle 1011 according to the gas density and pressure values, thereby connecting or disconnecting the contacts on the microswitches 101.

[0040] If a gas leak occurs, its density value drops to a certain level (reaching the alarm or lockout value), causing the Baden tube 4 to shift downwards. This displacement is transmitted to the connecting arm 13 via the temperature compensation element 3, and then to the connecting rod 6. The connecting rod 6 transmits this information to the transmission trigger mechanism 5, which in turn transmits it to the central shaft 52 via its fan-shaped shaft. The central shaft 52 then drives the corresponding signal adjustment mechanism 111 to rotate. When the gas density reaches a certain level, the signal adjustment mechanism 111 triggers the corresponding micro-switch 101's contact operation handle 1011, causing the corresponding micro-switch 101's contacts to connect and send out a corresponding signal (alarm or lockout). This monitors and controls the gas density in electrical switches and other equipment, ensuring the safe operation of the electrical equipment.

[0041] If its density value increases, the pressure value also increases accordingly. When it increases to a certain extent, the Baden tube 4 will also produce a corresponding upward displacement. Through the temperature compensation element 3, the connecting arm 13 will move upward and be transmitted to the connecting rod 6. The connecting rod 6 will transmit to the transmission trigger mechanism 5, and the sector shaft will transmit to the central shaft 52. The central shaft 52 will drive the corresponding signal adjustment mechanism 111. When it reaches a certain level, the signal adjustment mechanism 111 will not trigger the corresponding micro switch 101, and the corresponding micro switch 101 contacts will be disconnected, and the signal (alarm or lockout) will be released.

[0042] The contacts of the micro switch 101 are connected to the terminal block 15 via wire 31, and the terminal block 15 is fixed to the housing 8. The connector 9 is fixed to the housing 8. The watch glass 16, the cover 17, and their sealing rings are also fixed to the housing 8, protecting the internal structure of the housing 8 from mechanical damage and the intrusion of dirt and rainwater. A conduit is installed on the base 7 and is reliably sealed. The other end of the conduit is connected to the connector 9 and is reliably sealed. The switch reinforcement mechanism is fixed to the micro switch 101. When the switch is subjected to strong vibrations during opening and closing operations, it can prevent the housing 8 of the micro switch 101 from breaking and prevent the contact operation handle 1011 of the micro switch 101 from falling off. Therefore, it can greatly improve the vibration resistance of the relay and ensure the reliable operation of the system.

[0043] The transmission triggering mechanism 5 is a fan-shaped curved surface transmission mechanism. The transmission triggering mechanism 5 is connected to a signal conditioning mechanism 111, and is connected to a micro switch 101 through the signal conditioning mechanism 111. For example... Figure 5As shown, connecting arm 13 is connected to one end of connecting rod 6, and the other end of connecting rod 6 is connected to the starting end of transmission trigger mechanism 5; transmission trigger mechanism 5 is a sector-shaped curved surface transmission mechanism, which includes a movement shaft 50, a sector-shaped curved surface gear 51, a center gear 53, an upper clamping plate 55, and a lower clamping plate 56; the upper clamping plate 55 and the lower clamping plate 56 are fixed to the base at intervals and parallel to each other, and a sector-shaped curved surface gear shaft 510 is connected between the upper clamping plate 55 and the lower clamping plate 56. A transmission arm 511 extends radially from the center, and a sector-shaped curved gear 51 is mounted on a sector-shaped curved gear shaft 510. One end of the transmission arm 511 serves as the starting end of the transmission trigger mechanism 5 and is connected to the other end of the connecting rod 6. The central gear 53 serves as the amplification end of the transmission trigger mechanism 5 and is fixedly mounted on the core shaft 50 and meshes with the sector-shaped curved gear 51. Since the radius of the sector-shaped curved gear 51 is three times smaller than the radius of the central gear 53, it can amplify the signal. In this utility model, the gas density relay uses a micro switch 101 as the signal generator, and the control of the micro switch 101 contacts is entirely controlled by the transmission trigger mechanism 5 after amplification. By using this transmission trigger mechanism 5 to amplify the displacement, the vibration is reduced, achieving a shock absorption effect.

[0044] Example 2

[0045] like Figure 2-6 As shown, a remote-transmitting gas density relay differs from Embodiment 1 only in that:

[0046] The remote transmission unit also includes a pressure sensor 21, which is mounted on a printed circuit board 28 and connected to the intelligent processing unit 23 to collect pressure signals and transmit them to the intelligent processing unit 23. The pressure sensor 21 is sealed and fixed to the rear of the base 7, and its gas path is connected to the base 7, allowing it to contact the gas and accurately measure gas pressure values. The temperature sensor 20 and the pressure sensor 21 are connected to the intelligent processing unit 23 via an amplifier circuit 22.

[0047] The working principle or steps of the remote gas density relay in this embodiment are as follows: Pressure and temperature values ​​are measured by pressure sensor 21 and temperature sensor 20. The measured pressure and temperature signals are amplified by amplifier circuit 22. These amplified signals are then acquired by intelligent processing unit 23, which calculates the gas density value P20. This gas density value P20 is then transmitted over a long distance via communication module 26, thereby enabling online monitoring of the density, pressure, and temperature values ​​of the gas electrical equipment. Power module 24 provides operating power to other components of the remote transmission unit.

[0048] Example 3

[0049] like Figure 2-6As shown, a remote-transmitting gas density relay differs from Embodiment 1 only in that:

[0050] The remote transmission unit also includes a power module 24 for power supply, and a heat insulation component is provided at the power module 24. A shielding component is provided on the intelligent processing unit 23. The gas density relay also includes a heat insulation component, which is located at the power module 24 to reduce the impact of heat generated by the power module 24 on the temperature compensation element 3 and the temperature sensor 20.

[0051] In the remote transmission unit, the amplifier circuit 22, the intelligent processing unit 23, the power supply module 24, and the communication module 26 are fixed on the printed circuit board 28, which is located behind the base 7 and the housing 8. The amplifier circuit 22, the intelligent processing unit 23, the power supply module 24, and the communication module 26 are located around the pressure sensor 21. The power supply module 24 provides operating power to the temperature sensor 20, the pressure sensor 21, the amplifier circuit 22, the intelligent processing unit 23, and the communication module 26.

[0052] Example 4

[0053] like Figure 2-6 As shown, a remote-transmitting gas density relay differs from Embodiment 1 only in that:

[0054] To improve anti-interference capabilities, a surge protection circuit 25 for providing electromagnetic interference protection can also be added to the printed circuit board 28. The surge protection circuit 25 provides electromagnetic interference protection for the intelligent processing unit 23.

[0055] A fault indicator light 27 can also be added to the printed circuit board 28 to indicate the fault phenomenon.

[0056] A shielding component that can shield electric and magnetic fields can also be added to the printed circuit board 28. The shielding component is set outside the intelligent processing unit 23 to reduce the interference of external electric and magnetic fields on the intelligent processing unit 23.

[0057] The advantages of this invention are as follows: Long-distance transmission is achieved through the remote transmission unit, enabling online monitoring of the density, pressure, and temperature values ​​of gas electrical equipment. The design of the slot 1801 ensures that the temperature sensor 20 is in full contact with the surrounding environment, ensuring consistency with the environment of the temperature compensation element 3, thereby acquiring accurate temperature data and avoiding the influence of different environments. The fixing clip 1802 within the slot 1801 ensures stable and convenient assembly of the temperature sensor 20; installation is completed simply by insertion. The detachable fixing clip 1802 facilitates the replacement of the temperature sensor 20.

[0058] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.

Claims

1. A remote-transmitting gas density relay, comprising a housing (8), wherein a measuring unit and a remote-transmitting unit are provided inside the housing (8), the measuring unit comprising a Baden tube (4), a base (7), a temperature compensation element (3), and a signal generator, one end of the Baden tube (4) being connected to the base (7), and the other end being connected to the signal generator via the temperature compensation element (3); the remote-transmitting unit comprising a temperature sensor (20), an intelligent processing unit (23), and a communication module (26), wherein the intelligent processing unit (23) is connected to the temperature sensor (20) and the communication module (26) respectively, and is configured to collect the temperature signal collected by the temperature sensor (20), process it, and then transmit it via the communication module (26), characterized in that, An insulating block (18) is provided on the base (7), and a slot (1801) is provided on the upper part of the insulating block (18). A fixing clip (1802) is provided in the slot (1801), and the temperature sensor (20) is detachably connected to the slot (1801) through the fixing clip (1802).

2. The remote-transmission gas density relay according to claim 1, characterized in that, The remote transmission unit includes a printed circuit board (28), which is fixed on the base (7), and the intelligent processing unit (23) and the communication module (26) are disposed on the printed circuit board (28).

3. The remote-transmission gas density relay according to claim 2, characterized in that, The remote transmission unit also includes a pressure sensor (21), which is mounted on a printed circuit board (28) and connected to an intelligent processing unit (23) for collecting pressure signals and transmitting them to the intelligent processing unit (23).

4. The remote-transmission gas density relay according to claim 2, characterized in that, The remote transmission unit also includes a power supply module (24) for power supply, and the power supply module (24) is provided with a heat insulation component.

5. The remote-transmission gas density relay according to claim 2, characterized in that, The printed circuit board (28) is provided with a surge protection circuit (25).

6. The remote-transmission gas density relay according to claim 2, characterized in that, The printed circuit board (28) is equipped with a fault indicator light (27).

7. The remote-transmission gas density relay according to claim 1, characterized in that, The insulating block (18) has an assembly hole at its bottom, and the insulating block (18) is fixedly mounted on the base (7) by screws passing through the assembly hole.

8. The remote-transmission gas density relay according to any one of claims 1-7, characterized in that, The temperature sensor (20) is positioned close to the temperature compensation element (3), and the distance between the temperature sensor (20) and the temperature compensation element (3) is no more than 8 mm.

9. The remote-transmission gas density relay according to claim 8, characterized in that, The intelligent processing unit (23) is equipped with a shield.

10. The remote-transmission gas density relay according to claim 8, characterized in that, The communication module (26) is a wireless WAPI communication module, a wireless LORA communication module, or a wired RS485 communication module.

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