An agricultural irrigation control header

Abstract

The utility model discloses an agricultural irrigation control head, this agricultural irrigation control head includes box, safety device, controlling means, first access device and second access device, safety device is used for accessing external power supply, controlling means and safety device electricity are connected, first access device and controlling means electricity are connected, and first access device is used for accessing irrigation pump, and controlling means can power supply or power failure for first access device, second access device sets up multiple, and second access device all and controlling means electricity are connected, and second access device all are used for accessing electric valve, and controlling means can power supply or power failure for any one second access device, safety device, controlling means, first access device and all second access device all set up in the box. The utility model discloses an agricultural irrigation control head, simple and clear structure, and control process and control principle are simple and clear.

Description

Technical Field

[0001] This utility model relates to the field of agricultural irrigation, and in particular to an agricultural irrigation control head. Background Technology

[0002] Existing agricultural irrigation systems require multiple pumps to irrigate different agricultural areas due to the large size of the agricultural production area and the small flow rate of individual pumps. Furthermore, some production areas have different irrigation types, such as water resource irrigation and fertilizer irrigation, resulting in complex irrigation pipelines. Controlling irrigation is not only labor-intensive but also prone to errors. Therefore, some production areas have begun to purchase intelligent equipment for comprehensive control. However, these intelligent devices are expensive and highly specialized and confidential, causing many inconveniences. First, the high level of specialization requires professional personnel for installation, and actual use is also quite complex. Even if a simple equipment malfunction occurs, the production area personnel do not know where the problem is or how to repair it, requiring additional high repair costs to hire equipment company personnel for professional maintenance. In some agricultural window periods, delayed repairs can even cause significant losses. Second, the high level of specialization and confidentiality means that the internal workings of the intelligent equipment are strictly protected. Production area personnel cannot directly see the specific workings of the internal components. Even if they do disassemble it for observation, without high professional knowledge, it is easy to not understand the specific control principles of the equipment. Some equipment companies take advantage of this to commit fraud, producing equipment with very simple designs but complex appearances and high prices. Utility Model Content

[0003] This utility model aims to solve at least one of the technical problems existing in the prior art. To this end, this utility model proposes an agricultural irrigation control head with a simple and clear structure, and a simple and clear control process and control principle, which is convenient for agricultural production personnel to intuitively evaluate and purchase. After purchase, installation and maintenance are also very simple and convenient.

[0004] An agricultural irrigation control unit according to an embodiment of the present invention includes: a housing; a safety device for connecting to an external power source; a control device electrically connected to the safety device; a first access device electrically connected to the control device, the first access device being used to connect to an irrigation pump, and the control device being able to supply power to or de-energize the first access device; and multiple second access devices, each electrically connected to the control device, each second access device being used to connect to an electric valve, and the control device being able to supply power to or de-energize any one of the second access devices; the safety device, the control device, the first access device, and all the second access devices are all housed within the housing.

[0005] An agricultural irrigation control head according to an embodiment of the present utility model has at least the following technical effects: it is composed of a box, a safety device, a control device, a first access device and a second access device, with a simple and clear structure, and the control process and control principle are simple and clear, which makes it convenient for agricultural production area personnel to intuitively evaluate and purchase, and the installation and maintenance after purchase are also very simple and convenient.

[0006] According to some embodiments of this utility model, the safety device is a leakage current protection switch.

[0007] According to some embodiments of this utility model, the control device is a remote power controller.

[0008] According to some embodiments of the present invention, the control device includes a control switch and a sensor, the sensor and the control switch are electrically connected, the control switch and the safety device are electrically connected, the control switch and the first access device are electrically connected, the control switch and the second access device are electrically connected, and the control switch is disposed inside the housing.

[0009] According to some embodiments of the present invention, the agricultural irrigation control head further includes a third access device, the control device and the third access device are electrically connected, and the third access device and the safety device are electrically connected.

[0010] According to some embodiments of the present invention, the first access device includes an AC contactor and a first socket. The safety device is electrically connected to the AC contactor, and the AC contactor is electrically connected to the first socket. The first socket is used to connect the irrigation pump. The control device is electrically connected to the AC contactor, and the control device is capable of controlling the switching of the AC contactor.

[0011] According to some embodiments of this utility model, the second access device is a socket.

[0012] According to some embodiments of the present invention, at least two first access devices are provided, all of which are electrically connected to the control device, all of which are used to connect to an irrigation pump, and the control device is capable of supplying power to or de-energizing any one of the first access devices.

[0013] According to some embodiments of the present invention, the agricultural irrigation control head further includes the irrigation pump, and the irrigation pump is electrically connected to the first access device.

[0014] According to some embodiments of the present invention, the agricultural irrigation control head further includes the electric valve, which is electrically connected to any one of the second access devices.

[0015] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0016] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the overall structure and connection of the agricultural irrigation control head in an embodiment of this utility model.

[0017] Figure label: Box 100; Safety device 200; Control device 300; First access device 400, AC contactor 410, first socket 420; Second access device 500; Third access device 600; Irrigation pump 700; Electric valve 800. Detailed Implementation

[0018] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0019] In the description of this utility model, it should be understood that the directional descriptions, such as "up," "down," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "point," "inner," "outer," "axial," "radial," "circumferential," and "around," are based on the directional or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In the description of this utility model, sidewall refers to the left sidewall and / or the right sidewall.

[0020] In the description of this utility model, "multiple" means two or more; "greater than," "less than," "exceeding," etc., are understood to exclude the number itself; and "above," "below," "within," etc., are understood to include the number itself. Where "second" is used in the description, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the sequential relationship of the indicated technical features.

[0021] In the description of this utility model, it should be understood that "A is set on B" or "A is set on B" describes the connection or positional relationship between A and B, and does not mean that A is necessarily above B.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, movable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection of two components. "Bolt connection" and "screw connection" can be used interchangeably. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood in conjunction with the specific circumstances. It should be understood that multiple similar features in this utility model are only distinguished by different prefixes. Therefore, in this utility model, the feature name without distinguishing prefix (or the feature name with a partial prefix) is used to represent the combination of similar features of this type. For example, "access device" is used to represent the first access device 400, the second access device 500, the third access device 600, etc.

[0023] Reference Figure 1 According to an embodiment of the present invention, the agricultural irrigation control unit includes a housing 100, a safety device 200, a control device 300, a first access device 400, and a second access device 500. The safety device 200 is used to connect to an external power source. The control device 300 (control switch) is electrically connected to the safety device 200. The first access device 400 is electrically connected to the control device 300 and is used to connect to an irrigation pump 700. The control device 300 can supply power to or de-energize the first access device 400. Multiple second access devices 500 are provided, and each second access device 500 is electrically connected to the control device 300. Each second access device 500 is used to connect to an electric valve 800, and the control device 300 can supply power to or de-energize any one of the second access devices 500. The safety device 200, the control device 300, the first access device 400, and all the second access devices 500 are housed within the housing 100.

[0024] Agricultural irrigation can include water irrigation, fertilizer irrigation, pesticide irrigation, and combinations thereof (such as integrated water and fertilizer irrigation). The agricultural irrigation control head is the power source and control center for agricultural irrigation, capable of various adjustments to the irrigation process, such as controlling whether irrigation occurs, which area to irrigate, and what substances to irrigate. The housing 100 is a structure composed of multiple connected panels, with internal space for accommodating other components. The housing 100 may have an openable, movable door for easy closure when not in use. The housing 100 serves two purposes: firstly, it provides a relatively enclosed space, isolating the inside from the outside and preventing other organisms from contacting the components within, thus avoiding the risk of electric shock and protecting the components from damage by other organisms (such as rodents); secondly, it integrates all or most of the components of the agricultural irrigation control head within the housing 100, facilitating sales, transportation, installation, management, and maintenance.

[0025] External power sources are typically the local power grid (usually 220V or 380V), or power generation equipment (such as generators, generator trucks, solar panels), or energy storage devices (such as batteries). Safety device 200 connects to the external power source, usually directly via a power cord for greater safety and stability, but can also be connected via a plug (into a socket) or other methods. Safety device 200 is a device designed to ensure electrical safety; common examples include circuit breakers, residual current devices (RCDs), and fuses. By installing safety device 200, and ensuring that all subsequent components' power supply passes directly or indirectly through it, the safety of personnel and electrical equipment can be maximized. Furthermore, safety device 200 can have a built-in switch function, allowing for the active disconnection of power to other components, facilitating non-energized work. It should be understood that, in this embodiment, the description of "external power supply" is only to illustrate the structure of the agricultural irrigation control head and the functions generated by the structure. "External power supply" is not part of the structure of the agricultural irrigation control head, nor is it a limitation on the structure of the agricultural irrigation control head. That is, in the actual product, the agricultural irrigation control head may not include (or be connected to) an external power supply. It should also be understood that similar terms in other contents of this utility model (such as "irrigation pump 700", "electric valve 800", etc.) should also be understood with reference to this clause.

[0026] The control device 300, serving as the core of the agricultural irrigation control system, can supply power to or cut off power to other components. Operators control the system through the control device 300 to achieve intelligent and automated agricultural irrigation. It's important to understand that the control device 300, besides its power supply function, can also include other functions; for example, it can detect the moisture content, pH value, and conductivity of the irrigated soil, displaying the data in real time and even making judgments (issuing alarms, sending messages, etc.); it can also have network connectivity and remote control functions, connecting directly or indirectly to the operator's computer or mobile phone via wired or wireless connections, facilitating remote control of irrigation. Furthermore, combined with the aforementioned detection functions, it can monitor the actual condition of the farmland in real time, thereby determining whether irrigation should proceed. The control device 300 can utilize existing technologies, such as socket-controlled switches and remote sensor acquisition controllers. The electrical connection between the control device 300 and the safety device 200 can be made directly by wires (the control device 300 can have a built-in conversion circuit module) or by other access devices. This method is convenient for the disassembly, assembly, individual inspection and replacement of the control device 300, and facilitates later maintenance and upgrades. It is also because some types of control devices 300 have their own power plugs and cannot be directly connected to the high-voltage power supply of the power grid.

[0027] The access device, such as a socket, USB port, or terminal interface, is mainly used to distribute power from the safety device 200 to other components. The control device 300 is electrically connected to the access device, thereby controlling whether the safety device 200 supplies power to the components connected to the access device, thus achieving remote intelligent control. A pump is a machine that sucks in and discharges fluids, capable of drawing or pressing fluids into containers and lifting liquids to higher places. Specifically, in this invention, the irrigation pump 700 can pump agricultural irrigation liquids (such as water, fertilizer, pesticides, and combinations thereof) from specific containers, buildings, natural reservoirs, or other irrigation liquid sources into the delivery pipeline for subsequent irrigation of farmland. The control device 300 (electric control switch, AC contactor 410, safety device 200, external power supply) can supply power to the first access device 400. When the irrigation pump 700 is connected to the agricultural irrigation control head through the first access device 400, the irrigation pump 700 is powered on and can work normally. The control device 300 can control the irrigation operation by controlling whether the first access device 400 supplies power to the irrigation pump 700. It should be understood that "supply or de-supply" in "the control device 300 can supply or de-supply the first access device 400" means that the control device 300 can supply power to the first access device 400 for a certain period of time (or after a certain operation) and can de-supply the first access device 400 for another period of time (or after another operation). That is, the word "or" here means that the control device 300 can perform different actions at different times (after different operations), not that the control device 300 can only perform one of two actions. Similar terms in other contents of this utility model shall also be understood with reference to this clause. By setting up the access device and control device 300, especially when the access device is a socket, the production area staff can directly plug the water pump and electric valve 800 into the socket and use the irrigation control head to control irrigation, which is very simple and convenient.

[0028] The electric valve 800 (solenoid valve), a valve controlled by electricity, is a commonly used component in existing pipeline control technology. By controlling the electric valve 800 with electricity, the opening and closing of specific pipelines can be achieved, and even the flow rate and velocity of those pipelines can be adjusted. It's important to understand that existing agricultural production areas are large, while individual water pumps (i.e., irrigation pumps 700) have small flow rates. Simultaneously irrigating all areas of an agricultural production area is prone to uneven distribution due to terrain and pipeline layout, and can easily lead to insufficient water pressure and poor irrigation effects. Furthermore, some irrigation areas produce different products and require different types of irrigation at different times, and cannot irrigate the same liquid simultaneously. Therefore, a plot of land of hundreds of acres is usually divided into n irrigation districts, each approximately 10 acres (depending on the actual power of the water pump). A pump is installed at the source of the irrigation liquid, pumping the liquid from the source into the pipeline, which is then connected to each irrigation district. Each irrigation district is equipped with a... The lack of a valve to control the opening and closing of the broken pipeline, thus controlling which specific area to irrigate; in existing technology, valves are often manually operated, which is labor-intensive and prone to errors, such as opening the wrong valve, forgetting to close the valve (because after the water pump stops flowing, the workers subconsciously assume the work is done and forget to close the valve, and the irrigation liquid will flow into the wrong irrigation area the next time), is very troublesome. If an electric valve is installed, corresponding electronic equipment is required for control, so professional intelligent equipment (such as integrated water and fertilizer machine) needs to be purchased at a high price, and installation and maintenance are very inconvenient. Multiple electric valves 800 are installed, with one electric valve 800 equipped in each irrigation area. The electric valves 800 are connected to the agricultural irrigation control head via a second access device 500. The control device 300 then controls the power supply to these valves through the second access device 500, thus achieving intelligent control of irrigation operations in each irrigation area. It should be understood that the electric valves 800 in this invention are normally closed electric valves, meaning they can only be opened when energized and will automatically close and seal the pipeline after power is cut off. It should also be understood that the statement "safety device 200, control device 300, first access device 400, and all second access devices 500 are all housed within the housing 100" can mean that all of these devices are housed within the housing 100, or that at least a portion of each device is housed within the housing 100.It's important to understand that the control device 300 typically has corresponding buttons, keys, switches, and other control structures. Each connected device has its own control structure to operate (or, in other words, the control device 300 has control structures, and all connected devices (all first connected devices 400 and all second connected devices 500) have corresponding control structures) to control their power supply. Therefore, operators only need to perform simple operations (such as pressing buttons or turning switches on and off) to easily control irrigation. Consequently, the control device 300 usually has multiple control structures; for example, a 16-channel remote controller has 16 control structures to control 16 connected devices and their connected equipment. Furthermore, the control device 300 can be connected to the operator's computer or mobile phone via a network, allowing remote control of irrigation through specific operating software or programs (mini-programs, quick apps, etc.) and touch controls.

[0029] The structure, control principle, and control process of the above-mentioned agricultural irrigation control head are very simple and clear. Even if the staff in the agricultural production area are not highly professional, they can easily understand it. Therefore, the price is transparent and cheap, and the installation and maintenance are very simple. Some simple faults can be detected and repaired by the staff in the agricultural production area themselves.

[0030] Reference Figure 1 In some embodiments of this utility model, the safety device 200 is a leakage current protection switch.

[0031] A residual current device (RCD), also known as a residual current circuit breaker, is mainly used to protect equipment from leakage faults and to protect people from electric shock that could be fatal. It has overload and short circuit protection functions and can be used to protect lines or motors from overload and short circuit. It can also be used for infrequent switching and starting of lines under normal conditions, facilitating non-energized work.

[0032] Reference Figure 1 In some embodiments of this utility model, the control device 300 is a remote power controller.

[0033] The remote power controller, a current technology, has network connectivity. Based on its actual mechanical control structure and ability to operate on-site, it can remotely control irrigation operations via network connection to workers' computers, mobile phones, and other electronic devices.

[0034] Reference Figure 1In some embodiments of this utility model, the control device 300 includes a control switch and a sensor. The sensor and the control switch are electrically connected. The control switch is electrically connected to the safety device 200. The control switch is electrically connected to the first access device 400. The control switch is electrically connected to the second access device 500. The control switch is disposed inside the housing 100.

[0035] By setting up sensors on the irrigated land and controlling the switch via wired or wireless connection, data such as the moisture content, pH value, and conductivity of the irrigated land can be monitored in real time, enabling more intelligent and scientific irrigation operations.

[0036] Reference Figure 1 In some embodiments of this utility model, the agricultural irrigation control head also includes a third access device 600, the control device 300 and the third access device 600 are electrically connected, and the third access device 600 and the safety device 200 are electrically connected.

[0037] The connection is made through the third access device 600. This method is convenient for the disassembly, assembly, individual inspection and replacement of the control device 300, and facilitates later maintenance and upgrades. Also, some types of control devices 300 have their own power plugs, which can be connected to the agricultural irrigation control head through the third access device 600 (socket).

[0038] Reference Figure 1 In some embodiments of this utility model, the first access device 400 includes an AC contactor 410 and a first socket 420. The safety device 200 is electrically connected to the AC contactor 410, and the AC contactor 410 is electrically connected to the first socket 420. The first socket 420 is used to connect the irrigation pump 700. The control device 300 is electrically connected to the AC contactor 410 and can control the switching of the AC contactor 410.

[0039] The AC contactor 410 is an automatic switching electrical appliance that connects or disconnects the main circuit of a motor or load. It is an electrical appliance that uses electromagnetic force to close or open the switch. It is suitable for frequent operation and remote control of high-voltage circuits and has low-voltage release protection performance. In this embodiment, when the AC contactor 410 is open, the external power supply can be transmitted to the first socket 420 (irrigation pump 700) through the safety device 200 and the AC contactor 410. When the AC contactor 410 is closed, the external power supply cannot be transmitted to the first socket 420 (irrigation pump 700). The control device 300 can control the switching of the AC contactor 410 by operating the control structure. Because the irrigation pump 700 has a large power output, and some control devices 300 convert power through internal or external power plugs, resulting in a significant reduction in output voltage and current, these control devices 300 cannot meet the power requirements of the irrigation pump 700 and cannot drive its operation. Therefore, the first socket 420 and the safety device 200 are electrically connected to an external high-voltage power source. An AC contactor 410 (or other electrical control switch) is installed between the first socket 420 and the safety device 200, and the AC contactor 410 is electrically connected to the control device 300 (control switch). The control device 300 can control the start and stop of the irrigation pump 700 by controlling the switch of the AC contactor 410.

[0040] Reference Figure 1 In some embodiments of this utility model, the second access device 500 is a socket.

[0041] Irrigation pumps 700 and electric valves 800 generally come with plugs, so the connection device is set as a socket, which can facilitate the connection of irrigation pump 700; other connection devices can also be sockets (first socket 420, second socket, third socket), and even more advanced ones can be five-hole sockets, or even have built-in safety functions.

[0042] Reference Figure 1 In some embodiments of this utility model, at least two first access devices 400 are provided. All first access devices 400 are electrically connected to the control device 300. All first access devices 400 are used to connect to irrigation pumps 700 (at least one irrigation pump 700 is used to pump water, and at least one irrigation pump 700 is used to pump fertilizer). The control device 300 can supply power to or disconnect power to any one of the first access devices 400.

[0043] At least two access devices are set up, connecting to at least two irrigation pumps 700. One irrigation pump 700 can be used to pump water, and the other irrigation pump 700 can be used to pump fertilizer. The control device 300 connects and controls these devices, thus realizing intelligent water and fertilizer irrigation. Furthermore, each first access device 400 includes an AC contactor 410 and a first socket 420. The safety device 200 is electrically connected to all AC contactors 410. In each first access device 400, the AC contactor 410 and the first socket 420 are electrically connected, and the first socket 420 is used to connect the irrigation pump 700. The control device 300 is electrically connected to all AC contactors 410 and can control the switching of any one of the AC contactors 410.

[0044] Reference Figure 1 In some embodiments of this utility model, the agricultural irrigation control head also includes an irrigation pump 700, which is electrically connected to the first access device 400.

[0045] The basic model of the agricultural irrigation control unit does not include the irrigation pump 700. Agricultural production areas generally have their own or purchased irrigation pump 700. However, some newly established or expanding agricultural production areas lack the irrigation pump 700. Therefore, advanced models of the agricultural irrigation control unit can include the irrigation pump 700, facilitating unified purchase and configuration by agricultural production area staff without the need for separate procurement. It should be understood that multiple irrigation pumps 700 can be installed. Specifically, the number of irrigation pumps 700 can be equal to or less than the number of sockets for the first access device 400. The actual number can be set according to the actual situation.

[0046] Reference Figure 1 In some embodiments of this utility model, the agricultural irrigation control head also includes an electric valve 800, which is electrically connected to any one of the second access devices 500.

[0047] The basic model of the agricultural irrigation control head does not include the electric valve 800. However, some agricultural areas may not have installed electric valves 800 for irrigation control, or the installed electric valves 800 may be of the wrong type. Therefore, for these agricultural areas, an advanced model of the agricultural irrigation control head is specially configured, which includes electric valves 800. This allows agricultural staff to purchase and configure the equipment uniformly without needing to purchase them separately. It should be understood that one electric valve 800 can be installed (for example, if the agricultural area only needs one electric valve 800), or multiple electric valves 800 can be installed. Specifically, the number of electric valves 800 can be equal to or less than the number of sockets for the second access device 500. The more practical number can be set according to the actual situation (how many electric valves 800 are needed in the agricultural area).

[0048] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. An agricultural irrigation control head, characterized in that, include: Box; Safety device for connecting to external power supply; The control device is electrically connected to the safety device; A first access device is electrically connected to the control device. The first access device is used to access the irrigation pump. The control device can supply power to or disconnect power to the first access device. Multiple second access devices are provided, each of which is electrically connected to the control device. Each second access device is used to connect to an electric valve, and the control device can supply power to or de-energize any one of the second access devices. The safety device, the control device, the first access device, and all the second access devices are all housed within the enclosure.

2. The agricultural irrigation control head according to claim 1, characterized in that, The safety device is a leakage current protection switch.

3. The agricultural irrigation control head according to claim 1, characterized in that, The control device is a remote power controller.

4. The agricultural irrigation control head according to claim 1, characterized in that, The control device includes a control switch and a sensor. The sensor and the control switch are electrically connected. The control switch is electrically connected to the safety device, the control switch is electrically connected to the first access device, and the control switch is electrically connected to the second access device. The control switch is disposed inside the housing.

5. The agricultural irrigation control head according to claim 1, characterized in that, The agricultural irrigation control head also includes a third access device, the control device and the third access device are electrically connected, and the third access device and the safety device are electrically connected.

6. The agricultural irrigation control head according to claim 1, characterized in that, The first access device includes an AC contactor and a first socket. The safety device is electrically connected to the AC contactor, and the AC contactor is electrically connected to the first socket. The first socket is used to connect the irrigation pump. The control device is electrically connected to the AC contactor, and the control device is capable of controlling the switching of the AC contactor.

7. The agricultural irrigation control head according to claim 1, characterized in that, The second access device is a socket.

8. The agricultural irrigation control head according to claim 1, characterized in that, There are at least two first access devices, all of which are electrically connected to the control device. All of the first access devices are used to connect to the irrigation pump, and the control device can supply power to or disconnect power to any one of the first access devices.

9. The agricultural irrigation control head according to claim 1, characterized in that, The agricultural irrigation control unit also includes the irrigation pump, which is electrically connected to the first access device.

10. The agricultural irrigation control head according to claim 1, characterized in that, The agricultural irrigation control unit also includes the electric valve, which is electrically connected to any one of the second access devices.

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