Chemical oxygen demand (COD) sensor based on ultraviolet absorption method

Abstract

The utility model discloses a chemical oxygen demand (COD) sensor adopting an ultraviolet absorption method. The COD sensor comprises a light-emitting part and a receiving part connected with the light-emitting part through a connecting part, the light-emitting part comprises a base, an ultraviolet light-emitting tube, a visible light-emitting tube and a transmitting tube circuit board, the ultraviolet light-emitting tube and the visible light-emitting tube are located on the base and arranged side by side, the transmitting tube circuit board is located in the base, and pins of the ultraviolet light-emitting tube and pins of the visible light-emitting tube are connected with the transmitting tube circuit board; the receiving part comprises a sampling shell, an outer shell covering the sampling shell and a receiving tube circuit board located in the outer shell, an ultraviolet light receiving tube and a visible light receiving tube are arranged on the sampling shell side by side, and pins on the ultraviolet light receiving tube and the visible light receiving tube are connected with the receiving tube circuit board; monochromatic light emitted by the ultraviolet light emitting tube and the visible light emitting tube can be received by the ultraviolet light receiving tube and the visible light receiving tube respectively. The device is quick, simple and convenient to use, does not need chemical reagents during detection, has no secondary pollution, is easy to realize automation, and can ensure the measurement precision.

Description

TECHNICAL FIELD

[0001] The utility model relates to water quality detection equipment technical field especially relates to a kind of ultraviolet absorption method chemical oxygen demand COD sensor. BACKGROUND

[0002] Oxygen demand COD (Chemical Oxygen Demand) refers to the amount of reducing substances in water sample that need to be oxidized. The current oxygen demand COD detection methods include potassium dichromate method, potassium permanganate method, spectrophotometry and electrochemical method.

[0003] Among them, the principle of potassium dichromate method is that potassium dichromate oxidizes organic matter and reducing substances in water under strong acidic conditions, and the remaining potassium dichromate is titrated with ferrous ammonium sulfate. The COD is calculated by the amount of consumed potassium dichromate. However, this method uses toxic reagents and requires proper disposal of waste liquid, resulting in complex operation and long time consumption. The potassium permanganate method is that potassium permanganate oxidizes organic matter and reducing substances in water under acidic or alkaline conditions, and the COD is calculated by the amount of consumed potassium permanganate. However, the oxidation ability is weak and not suitable for high-concentration organic wastewater. The spectrophotometry uses strong oxidizing agents (such as potassium dichromate) to rapidly digest organic matter in water samples under high temperature and pressure. The absorbance of the digested solution is measured by a spectrophotometer, and the COD value is calculated. However, a special spectrophotometer is required, and the equipment is relatively expensive. Suspended solids, color and other factors in water samples can interfere with the measurement results and need to be pretreated. The electrochemical method uses an electrochemical sensor to measure the current or potential change generated by the oxidation of organic matter in water samples, and indirectly calculates the COD value. However, the electrode is easily contaminated and corroded, and needs to be cleaned and replaced regularly. The measurement range is relatively narrow, and high-concentration COD water samples need to be diluted.

[0004] Therefore, it is necessary to provide a ultraviolet absorption method chemical oxygen demand COD sensor to solve the above problems. UTILITY MODEL CONTENT

[0005] To overcome the above-mentioned shortcomings, the purpose of the utility model is to provide a ultraviolet absorption method chemical oxygen demand COD sensor, which is fast and easy to use, does not need to add chemical reagents during detection, has no secondary pollution, is easy to realize automation, and can ensure measurement accuracy.

[0006] In order to achieve the above object, the utility model adopts the technical scheme: a kind of ultraviolet absorption method chemical oxygen demand COD sensor, including emitting part and the receiving part being connected by connecting part with it;The emitting part includes base, ultraviolet light emitting tube and visible light emitting tube located on it and arranged side by side and the emission tube circuit board located in base, the pin of ultraviolet light emitting tube and visible light emitting tube is connected with emission tube circuit board, the receiving part includes sampling shell, the outer shell being covered on it and the receiving tube circuit board located in outer shell, ultraviolet light receiving tube and visible light receiving tube are arranged side by side on the sampling shell, and the pin on it is connected with receiving tube circuit board, the monochromatic light emitted by ultraviolet light emitting tube and visible light emitting tube can be received by ultraviolet light receiving tube and visible light receiving tube respectively.

[0007] Further, the base is provided with an ultraviolet light filter and a visible light filter corresponding to the emitting end positions of the ultraviolet light emitting tube and the visible light emitting tube, respectively, and the sampling shell is also provided with an ultraviolet light filter and a visible light filter corresponding to the receiving end positions of the ultraviolet light receiving tube and the visible light receiving tube, respectively. The ultraviolet light filter and the visible light filter are arranged at the corresponding positions of the ultraviolet light receiving tube, the visible light receiving tube, the ultraviolet light emitting tube and the visible light emitting tube, respectively, so that only the light of the specified wavelength is received by the ultraviolet light receiving tube or the visible light receiving tube after the light passes through the ultraviolet light filter or the visible light filter, thereby achieving good anti-interference effect and making the measurement of the absorbance of COD and the absorbance of turbidity more accurate.

[0008] Further, the monochromatic light emitted by the ultraviolet light emitting tube has a wavelength of 254 nm, and the monochromatic light emitted by the visible light emitting tube has a wavelength of 546 nm. The absorbance of COD and the absorbance of turbidity can be accurately detected by using monochromatic light of a specific wavelength. The wavelengths of 254 nm and 546 nm of the monochromatic light have better wavelength performance than other wavelengths when detecting.

[0009] Further, the emitting part further includes a bottom cover, the base is open at the bottom and is threadedly connected with the bottom cover, two first placing grooves and a second placing groove for embedding the photoelectric tube supports one are formed in the base along the height direction thereof, and the ultraviolet light emitting tube and the visible light emitting tube are respectively located in the corresponding photoelectric tube supports one. The open bottom of the base provides installation space for the emission tube circuit board, and the two photoelectric tube supports one are respectively used for placing the ultraviolet light emitting tube and the visible light emitting tube to protect them.

[0010] Furthermore, the receiving unit also includes two fourth placement slots opening downwards from the top of the sampling housing. Each fourth placement slot contains a phototube support for placing the ultraviolet light receiving tube and the visible light receiving tube. Each fourth placement slot has a third placement slot extending outwards from its bottom, facing the bottom of the sampling housing. The two third placement slots are used to place the ultraviolet light filter and the visible light filter, respectively. The phototube supports in the two fourth placement slots provide support for the ultraviolet light receiving tube and the visible light receiving tube, while the filters in the two third placement slots further remove stray light from the environment, preventing it from affecting subsequent absorbance detection.

[0011] Furthermore, an annular circuit board mounting bracket is provided along the inner wall of the outer housing, and a top cover is threadedly connected to the top of the outer housing. The annular shape of the circuit board mounting bracket serves two purposes: it securely holds the receiving tube circuit board, and it does not interfere with the connection between the pins of the visible light receiving tube and the ultraviolet light receiving tube and the receiving tube circuit board. The threaded connection between the top cover and the outer housing facilitates subsequent real-time disassembly, maintenance, and replacement of components inside the outer housing.

[0012] Furthermore, a cleaning assembly is included, comprising a silicone brush and a servo motor that drives it to rotate back and forth. The servo motor is located on the top of the sampling housing, and its drive end has a rotating shaft. The end of the rotating shaft away from the servo motor is rotatably connected to the base via a bearing. The silicone brush is located between the upper surface of the base and the lower surface of the sampling housing and is sleeved on the rotating shaft. When the sensor is placed in a water sample for detection, the servo motor drives the silicone brush to rotate left and right to clean the ultraviolet and visible light filters located on its upper and lower sides, preventing impurities in the water sample from affecting the detection of absorbance.

[0013] Furthermore, a cable clamping connector is provided on the top of the cover.

[0014] The beneficial effects of this utility model are:

[0015] This invention is quick and easy to use, requires no chemical reagents during testing, causes no secondary pollution, and is easily automated. It can be conveniently integrated into online monitoring systems to monitor COD changes in water bodies in real time and continuously, providing strong support for dynamic monitoring and early warning of water quality. At the same time, it uses multi-segment turbidity standard solution and multi-segment COD standard solution for calibration, converting the absorbance of turbidity to visible light into absorbance to ultraviolet light, which has a turbidity compensation function and can further ensure measurement accuracy. Attached Figure Description

[0016] Figure 1 This is an axonometric view of the overall structure of an embodiment of the present invention;

[0017] Figure 2It is an embodiment of the whole structure cross section schematic view of the utility model;

[0018] Figure 3 It is another whole structure cross section schematic view of an embodiment of the utility model;

[0019] Figure 4 It is the photoelectric tube support one and ultraviolet light emitting tube whole structure axial side view of an embodiment of the utility model;

[0020] In the figure: 1, cable holds tightly and connects; 2, light emitting part; 21, base; 22, bottom cover; 23, emitting tube circuit board; 24, photoelectric tube support one; 25, sealing ring; 26, first placement groove; 27, second placement groove; 28, ultraviolet light emitting tube; 29, visible light emitting tube; 3, receiving part; 31, external shell; 32, sampling shell; 33, top cover; 34, receiving tube circuit board; 35, circuit board fixing frame; 36, rudder machine; 37, third placement groove; 38, fourth placement groove; 39, photoelectric tube support two; 310, ultraviolet light receiving tube; 311, visible light receiving tube; 4, connecting part; 5, cleaning assembly; 51, rotating shaft; 52, silica gel brush; 6, ultraviolet light filter; 7, visible light filter. DETAILED DESCRIPTION

[0021] The preferred embodiments of the utility model are described in detail below in combination with the drawings, so that the advantages and features of the utility model can be more easily understood by the person skilled in the art, and the protection scope of the utility model can be more clearly and explicitly defined.

[0022] In the prior art, the detection of water samples also uses ultraviolet light absorption method, which indirectly estimates the COD value by measuring the absorbance of water samples at a specific wavelength using ultraviolet light absorption characteristics. However, when the ultraviolet absorption method is used to detect the oxygen demand of water samples, the transparency and turbidity of the water samples have high requirements, and the suspended solids, colloids, color and the like in the water samples will scatter or absorb ultraviolet light, resulting in inaccurate measurement results.

[0023] Therefore, referring to the drawings, Figures 1-4 The application provides a kind of chemical oxygen demand COD sensor of ultraviolet absorption method, including light emitting part 2 and receiving part 3 connected by connecting part 4;The light emitting part 2 includes base 21, ultraviolet light emitting tube 28 and visible light emitting tube 29 located on it and arranged side by side and emitting tube circuit board 23 located in base 21, the pins of ultraviolet light emitting tube 28 and visible light emitting tube 29 are connected with emitting tube circuit board 23, the distribution of power can be controlled by emitting tube circuit board 23, in turn control ultraviolet light emitting tube 28 and visible light emitting tube 29 open and close;Base 21 provides support and protection for the setting of ultraviolet light emitting tube 28, visible light emitting tube 29 and emitting tube circuit board 23.

[0024] Specifically, when the entire COD sensor is placed in the water sample to be detected, the emission tube circuit board 23 controls the ultraviolet light emitting tube 28 and the visible light emitting tube 29 to be turned on, and the receiving part 3 emits specific wavelength ultraviolet light and visible light. The receiving part 3 receives and detects the absorbance of COD and turbidity.

[0025] The receiving part 3 includes a sampling shell 32, an outer shell 31 covering the sampling shell 32, and a receiving tube circuit board 34 located in the outer shell 31, wherein the sampling shell 32 can provide support and protection for the ultraviolet light receiving tube 310 and the visible light receiving tube 311. Specifically, the receiving tube circuit board 34 is arranged above the ultraviolet light receiving tube 310 and the visible light receiving tube 311, and the pins of the ultraviolet light receiving tube 310 and the visible light receiving tube 311 are arranged towards the receiving tube circuit board 34, so that the pins can be connected to the receiving tube circuit board 34 without interfering with the reception of specific light by the ultraviolet light receiving tube 310 and the visible light receiving tube 311.

[0026] The ultraviolet light receiving tube 310 and the visible light receiving tube 311 are arranged side by side on the sampling shell 32, and their pins are connected to the receiving tube circuit board 34. The monochromatic light emitted by the ultraviolet light emitting tube 28 and the visible light emitting tube 29 can be received by the ultraviolet light receiving tube 310 and the visible light receiving tube 311, respectively. After the monochromatic light emitted by the ultraviolet light emitting tube 28 and the visible light emitting tube 29 is received by the ultraviolet light receiving tube 310 and the visible light receiving tube 311, respectively, the information data is transmitted to the external processor through the receiving tube circuit board 34, and the corresponding absorbance of COD and turbidity can be quickly calculated.

[0027] In the above process of detecting the absorbance of COD and turbidity, no chemical reagent is used in the water sample, and no secondary pollution is caused. The detection results can be quickly and conveniently integrated into an online monitoring system for real-time and continuous monitoring of the change of COD concentration in water, providing strong support for dynamic monitoring and early warning of water quality. At the same time, multiple turbidity standard liquids and multiple COD standard liquids are used for calibration, the absorbance of turbidity to visible light is converted to the absorbance of turbidity to ultraviolet light, which has a turbidity compensation function and can further ensure the measurement accuracy.

[0028] Specifically, according to the above absorbance of turbidity, the turbidity in the water sample is calculated, and the turbidity is compensated according to the turbidity, which effectively reduces the interference of turbidity on the measurement of COD concentration, and the COD concentration is accurately calculated according to the data calibrated by the multiple COD standard liquids and the absorbance of COD.

[0029] In some embodiments, the connecting part 4 is integrally formed at the lower part of the sampling shell 32, and the end thereof away from the sampling shell 32 is detachably connected to the upper surface of the base 21. The connection through the connecting part 4 ensures that the ultraviolet light emitting tube 28 and the ultraviolet light receiving tube 310, and the visible light emitting tube 29 and the visible light receiving tube 311 are in corresponding positions, and also leaves sufficient space for water sampling.

[0030] The base 21 is provided with an ultraviolet light filter 6 and a visible light filter 7 at positions corresponding to the emitting ends of the ultraviolet light emitting tube 28 and the visible light emitting tube 29, respectively. The sampling shell 32 is also provided with an ultraviolet light filter 6 and a visible light filter 7 at positions corresponding to the receiving ends of the ultraviolet light receiving tube 310 and the visible light receiving tube 311, respectively. The ultraviolet light filter 6 and the visible light filter 7 are arranged at corresponding positions of the ultraviolet light receiving tube 310, the visible light receiving tube 311, the ultraviolet light emitting tube 28 and the visible light emitting tube 29, so that only light of a specified wavelength is received by the ultraviolet light receiving tube 310 or the visible light receiving tube 311 after being filtered by the ultraviolet light filter 6 or the visible light filter 7, thereby achieving good anti-interference effect and making the measurement of the absorbance of COD and the absorbance of turbidity more accurate.

[0031] The monochromatic light emitted by the ultraviolet light emitting tube 28 has a wavelength of 254 nm, and the monochromatic light emitted by the visible light emitting tube 29 has a wavelength of 546 nm. The monochromatic light of a specific wavelength can accurately detect the absorbance of COD and the absorbance of turbidity, respectively. The wavelengths of 254 nm and 546 nm have better effects than other wavelengths in detection.

[0032] The light emitting part 2 further comprises a bottom cover 22. The base 21 is open at the bottom and is threadedly connected with the bottom cover 22. Two first placing grooves 26 for embedding the photoelectric tube supports I 24 are formed in the base 21 along the height direction thereof. The ultraviolet light emitting tube 28 and the visible light emitting tube 29 are respectively located in the corresponding photoelectric tube supports I 24. The opening at the bottom of the base 21 provides installation space for the emitting tube circuit board 23. The two photoelectric tube supports I 24 are respectively used for placing the ultraviolet light emitting tube 28 and the visible light emitting tube 29 to protect them.

[0033] Specifically, referring to the drawings, Figure 3 A groove matching the opening in the base 21 is formed at the top of the bottom cover 22. After the base 21 and the bottom cover 22 are threadedly connected, the groove and the opening in the base 21 form the above-mentioned installation space. A sealing ring 25 is wrapped around the circumference of the bottom cover 22 at the connection between the bottom cover 22 and the base 21, so as to ensure that no water enters the light emitting part 2 when the entire sensor is placed in water sample for detecting water quality, thereby preventing damage to the emitting tube circuit board 23.

[0034] The first placing groove 26 has a second placing groove 27 opened at the top thereof towards the direction of the top of the base 21, for placing the ultraviolet light filter 6 and the visible light filter 7, so that the light emitted by the ultraviolet light emitting tube 28 and the visible light emitting tube 29 can be respectively received by the ultraviolet light receiving tube 310 and the visible light receiving tube 311 after being filtered by the corresponding filter, and the stray light is filtered out, so that only the light of specific wavelength can be transmitted to the two receiving tubes, avoiding the influence of stray light on the detection of absorbance.

[0035] The receiving part 3 further comprises two fourth placing grooves 38 opened downward from the top of the sampling shell 32, and each of the fourth placing grooves 38 is provided with a photoelectric tube support 39 for placing the ultraviolet light receiving tube 310 and the visible light receiving tube 311. The bottom of each of the fourth placing grooves 38 is provided with a third placing groove 37 extending from the bottom thereof, and the two third placing grooves 37 are respectively used for placing the ultraviolet light filter 6 and the visible light filter 7. The photoelectric support 39 provided in the two fourth placing grooves 38 supports the ultraviolet light receiving tube 310 and the visible light receiving tube 311, and the filters provided in the two third placing grooves 37 can remove the external stray light, avoiding the influence of the stray light on the subsequent detection of absorbance.

[0036] It should be noted that the ultraviolet light emitting tube 28 and the ultraviolet light receiving tube 310, the visible light emitting tube 29 and the visible light receiving tube 311 are one-to-one corresponding.

[0037] The inner wall of the outer shell 31 is provided with an annular circuit board fixing frame 35, and the top of the outer shell 31 is threadedly connected with a top cover 33. The circuit board fixing frame 35 is annular, which can be used for fixedly placing the receiving tube circuit board 34, and will not affect the connection between the pins of the visible light receiving tube 311 and the ultraviolet light receiving tube 310 and the receiving tube circuit board 34. The threaded connection of the top cover 33 and the outer shell 31 facilitates the real-time disassembly, maintenance and replacement of the parts inside the outer shell 31.

[0038] The cleaning assembly 5 comprises a silica gel brush 52 and a steering wheel 36 capable of driving the silica gel brush 52 to rotate back and forth, and the steering wheel 36 is arranged at the top of the sampling shell 32, and a rotating shaft 51 is arranged at the driving end of the steering wheel 36. One end of the rotating shaft 51 away from the steering wheel 36 is rotatably connected to the base 21 through a bearing, and the silica gel brush 52 is located between the upper surface of the base 21 and the lower surface of the sampling shell 32 and is sleeved on the rotating shaft 51. When the sensor is placed in the water sample for detection, the steering wheel 36 can drive the silica gel brush 52 to rotate left and right to clean the ultraviolet light filter 6 and the visible light filter 7 on the upper and lower sides of the silica gel brush 52, avoiding the influence of impurities in the water sample on the detection of absorbance.

[0039] The top cover 33 is provided with a cable grip joint 1 at the top. In order to externally connect the power supply of the sensor, and transmit the absorbance data of COD and turbidity to the external controller through the cable grip joint 1, so that the staff can view it in real time.

[0040] The specific use is as follows:

[0041] The steps include:

[0042] S1: The absorbance of turbidity is measured by using multi-section turbidity standard solution, and the equation y of turbidity absorbance z and turbidity x is established;

[0043] S2: The COD sensor is placed in turbidity standard solution 1 with turbidity x1, and the absorbance (r11) of COD standard solution 1 and the absorbance (r12) of COD standard solution 2 are measured; the COD sensor is placed in turbidity standard solution 2 with turbidity x2, and the absorbance (r21) of COD standard solution 1 and the absorbance (r22) of COD standard solution 2 are measured;

[0044] S3: The equation y1 of turbidity and the absorbance of COD standard solution 1 is established through (x1, r11) and (x2, r21);

[0045] The equation y2 of turbidity and the absorbance of COD standard solution 2 is established through (x1, r12) and (x2, r22);

[0046] S4: The COD sensor is placed in the water sample to be detected, and the absorbance z0 (known) of turbidity and the absorbance r0 (known) of COD are read out;

[0047] S5: The equation y3 of COD absorbance (r) and COD concentration under the current turbidity x is established according to the known values in S4;

[0048] Specifically, the absorbance z0 of turbidity is substituted into the equation y in S1, the current turbidity x is calculated, the current turbidity x is substituted into the two equations y1 and y2 in S3 respectively, and the absorbance r1 under the COD standard solution 1 and the absorbance r2 under the COD standard solution 2 under the current turbidity x are obtained;

[0049] Through (r1, the known COD concentration in the COD standard solution 1) and (r2, the known COD concentration in the COD standard solution 2), the equation y3 of COD absorbance (r) and COD concentration under the current turbidity x is established.

[0050] S6: The COD absorbance r0 is substituted into the equation y3, and the COD concentration is finally calculated.

[0051] It should be noted that the turbidity standard solution is a turbid solution prepared by a user according to a standard value; the COD standard solution 1 and the COD standard solution 2 are standard solutions prepared by the user according to standard values, and the concentrations of COD in the two standard solutions are known.

[0052] The above embodiments are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it, and cannot limit the protection scope of the present application. Any equivalent changes or modifications made according to the spirit and essence of the present application should be covered within the protection scope of the present application.

Claims

1. A UV absorption chemical oxygen demand (COD) sensor, characterized in that: The device includes a light-emitting part and a receiving part connected to it via a connecting part. The light-emitting part includes a base, an ultraviolet light-emitting tube and a visible light-emitting tube arranged side by side on the base, and an emitting tube circuit board located inside the base. The pins of the ultraviolet light-emitting tube and the visible light-emitting tube are all connected to the emitting tube circuit board. The receiving part includes a sampling housing, an outer housing covering it, and a receiving tube circuit board located inside the outer housing. An ultraviolet light receiving tube and a visible light receiving tube are arranged side by side on the sampling housing, and their pins are all connected to the receiving tube circuit board. The monochromatic light emitted by the ultraviolet light-emitting tube and the visible light-emitting tube can be received by the ultraviolet light receiving tube and the visible light receiving tube, respectively.

2. The ultraviolet absorption chemical oxygen demand (COD) sensor according to claim 1, characterized in that: An ultraviolet filter and a visible light filter are respectively provided on the base at the positions corresponding to the emitting ends of the ultraviolet light-emitting tube and the visible light-emitting tube. An ultraviolet filter and a visible light filter are also respectively provided on the sampling housing at the positions corresponding to the receiving ends of the ultraviolet light-receiving tube and the visible light-receiving tube.

3. The ultraviolet absorption chemical oxygen demand (COD) sensor according to claim 1, characterized in that: The ultraviolet light-emitting tube emits monochromatic light with a wavelength of 254 nm, and the visible light-emitting tube emits monochromatic light with a wavelength of 546 nm.

4. The ultraviolet absorption chemical oxygen demand (COD) sensor according to claim 1, characterized in that: The light-emitting part also includes a bottom cover. The bottom of the base is open and threadedly connected to the bottom cover. The base has two placement slots along its height direction, namely a first placement slot and a second placement slot, for embedding a phototube bracket. The ultraviolet light-emitting tube and the visible light-emitting tube are respectively located in the corresponding phototube brackets.

5. The ultraviolet absorption chemical oxygen demand (COD) sensor according to claim 1, characterized in that: The receiving unit also includes two fourth placement slots that are opened downward from the top of the sampling housing. Each of the fourth placement slots is provided with a phototube bracket for placing an ultraviolet light receiving tube and a visible light receiving tube. Each of the fourth placement slots has a third placement slot extending outward from the bottom of the sampling housing. The two third placement slots are respectively used to place an ultraviolet light filter and a visible light filter.

6. The ultraviolet absorption chemical oxygen demand (COD) sensor according to claim 5, characterized in that: An annular circuit board mounting bracket is provided inside the outer housing along its inner wall, and a top cover is threadedly connected to the top of the outer housing.

7. The ultraviolet absorption chemical oxygen demand (COD) sensor according to claim 1, characterized in that: It also includes a cleaning assembly, which includes a silicone brush and a servo motor that drives it to rotate back and forth. The servo motor is located on the top of the sampling housing, and its driving end is provided with a rotating shaft. The end of the rotating shaft away from the servo motor is rotatably connected to the base through a bearing. The silicone brush is located between the upper surface of the base and the lower surface of the sampling housing and is sleeved on the rotating shaft.

8. A chemical oxygen demand (COD) sensor based on ultraviolet absorption according to claim 6, characterized in that: A cable clamping connector is provided on the top of the cover.

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