A Meter Reading Method, System, and Storage Medium Based on Dynamic Device Addresses

Abstract

This application relates to the technical field of power meters, and in particular, to a meter reading method, system, and storage medium based on dynamic device addresses, which include the following steps: obtaining the first feedback signal of each electric meter, and eliminating the same addresses in all device addresses to obtain an address list set; regularly obtaining the response feedback signal of each electric meter, and sequentially matching the device address in the address list set; if no match is found, obtaining a specified address, using the specified address as the device address corresponding to the electric meter, and storing it in the address list set; after regularly obtaining the response feedback signal of each electric meter, obtaining a data acquisition signal, and obtaining the electric meter data based on the device address according to the data acquisition signal. This application can distinguish electric meters with the same device address by matching the device addresses of the electric meters multiple times, so as to record the data of the electric meters more accurately.

Description

Technical Field

[0001] This application relates to the technical field of power meters, and in particular, to a meter reading method, system, and storage medium based on dynamic device addresses. Background Art

[0002] RS-485 interfaces can be connected for communication. Therefore, RS-485 can directly perform data transmission through RS-485 networking without the need to build an internal communication module. Due to the advantages of high cost performance, low cost, and convenient construction of RS-485 meter reading, the RS-485 meter reading solution is suitable for occasions where meters are installed centrally, such as office buildings and residential areas. The RS-485 meter reading solution includes a concentrator and a master station system network-connected to the concentrator. The concentrator is installed in the area where meters are concentrated. All meters in this area transmit data to the concentrator, and then the concentrator transmits the data to the master station system, thereby realizing the meter reading operation for this area.

[0003] After the meter leaves the factory, each meter has a unique meter number. According to the intelligent meter DLMS meter reading communication protocol, generally, the lower 4 bits of the meter number are added to 16 to obtain the device address of the meter's RS-485. The meter uses this device address to transmit data to the concentrator.

[0004] However, in actual use, when more meters are installed on the same concentrator, it is easy to have meters with different meter numbers but the same device address. In this case, meters with the same device address will simultaneously respond to the concentrator for data, resulting in data transmission conflicts in the concentrator and the inability to obtain the data of the corresponding meters. The relevant solution is to manually remove the meters with the same device address, or install the meters with the same device address under different concentrators before installing the meters, which will increase labor costs and time costs and reduce the efficiency of the concentrator in obtaining meter data. Summary of the Invention

[0005] In order to reduce labor costs and time costs and improve the addressing efficiency between the concentrator and the meters, this application provides a meter reading method, system, and storage medium based on dynamic device addresses.

[0006] In a first aspect, this application provides a meter reading method based on dynamic device addresses, adopting the following technical solution:

[0007] A meter reading method based on dynamic device addresses includes the following steps:

[0008] Step S100, obtain the first feedback signal of each meter, where the first feedback signal includes the device address, and remove the same addresses in all device addresses to obtain an address list set;

[0009] Step S200, regularly obtain the response feedback signal of each electricity meter, where the response feedback signal includes the device address corresponding to the electricity meter, and sequentially match the device address in the address list set;

[0010] Step S300, if no match is found, obtain a specified address, where the specified address is different from all the addresses in the address list set, use the specified address as the device address corresponding to the electricity meter, and store it in the address list set. Step S400, after regularly obtaining the response feedback signal of each electricity meter, obtain a data acquisition signal, and obtain the electricity meter data based on the device address according to the data acquisition signal.

[0011] By adopting the above technical solution, by obtaining the device addresses of the electricity meters and eliminating the same addresses among all the device addresses, an address list set is obtained. Then, regularly obtain the response feedback signal of the electricity meters, match the obtained device addresses in the address list set. If no match is found, generate a specified address different from the address list set, and store the specified address in the address list set. Through multiple matches, the electricity meters with the same device address can be distinguished. Thus, after regularly obtaining the response feedback signal of each electricity meter, obtain a data acquisition signal, and obtain the electricity meter data based on the device address according to the data acquisition signal, which can more accurately record the data of each electricity meter in the address list set.

[0012] Preferably, the first feedback signal further includes a feedback time, and the feedback time and the device address are in one-to-one correspondence. Among them, the obtaining of the address list set includes the following steps:

[0013] Obtain all the device addresses in the address list set;

[0014] Obtain a time list according to the feedback time corresponding to the device address, where the time list contains a unique time, and the unique time represents a feedback time without repeated time;

[0015] Use the time list set as the new address list set.

[0016] By adopting the above technical solution, after distinguishing the electricity meters with the same device address, obtain the device address based on the address list set, and obtain the corresponding feedback time. Obtain a time list containing unique time from the feedback time, and then control the time to obtain the response feedback signal of the electricity meters, so that all electricity meters pass through the RS-485 bus at different times, thereby improving the accuracy of data acquisition of the RS-485 for the electricity meters.

[0017] Preferably, the regularly obtaining the response feedback signal of each electricity meter includes the following steps:

[0018] Obtain a first specified time, and repeat using the first specified time as a countdown;

[0019] When the countdown of the first specified time ends, generate and send a device address query instruction, and receive a response feedback signal according to the device address query instruction.

[0020] By adopting the above technical solution, repeating using the first specified time as a countdown, when the countdown of the first specified time ends, the concentrator will resend a device address query instruction once, and then obtain the response feedback signal of the electric meter corresponding to the concentrator according to the device address query instruction, so as to be able to obtain the response feedback signal regularly, thereby improving the addressing efficiency of the electric meter and being able to obtain all electric meter data more quickly.

[0021] Preferably, the obtaining of the first specified time includes the following steps:

[0022] Obtain the number of electric meter devices, and the number of electric meter devices represents the total number of electric meters;

[0023] Obtain the first specified time according to the number of electric meter devices and a preset list, and the preset list represents a relationship list between the number of electric meters and the first specified time.

[0024] By adopting the above technical solution, obtain the corresponding first specified time through the number of electric meter devices, and then be able to adaptively set the first specified time according to the actual situation, improve the response efficiency of all electric meters, and be able to obtain the data of all electric meters in a timely manner.

[0025] Preferably, the receiving of the response feedback signal according to the device address query instruction includes the following steps:

[0026] Randomly obtain a specified multiple corresponding to each electric meter, and the specified multiple is greater than 1;

[0027] Take the product of the specified multiple and a preset reference time as the second specified time corresponding to the electric meter;

[0028] Use the second specified time as a countdown, and when the second specified time ends, receive the response feedback signal corresponding to each electric meter according to the device address query instruction.

[0029] By adopting the above technical solution, based on the randomly selected specified multiple, obtain the second specified time, use the second specified time as a countdown, and after the countdown ends, obtain the response feedback signal of the electric meter, so as to be able to control the acquisition of the response feedback signal of each electric meter, so that all electric meters can transmit data through RS-485 at different times, improving the accuracy of electric meter data transmission.

[0030] Preferably, after obtaining the first specified time according to the number of the electricity meter devices and the preset list, the following steps are further included:

[0031] Obtain the number of initial electricity meters according to the address list set, where the number of initial electricity meters represents the number of electricity meters initially stored in the address list set;

[0032] Obtain the replacement time according to the number of initial electricity meters and the preset list, and use the replacement time as the first specified time.

[0033] By adopting the above technical solution, the number of initial electricity meters is obtained according to the address list set, the time for regularly obtaining the response feedback signals of each electricity meter is dynamically adjusted, and according to the actually obtained number of initial electricity meters, the addressing time for the electricity meters is shortened, the corresponding device addresses can be obtained as soon as possible, and thus the meter reading efficiency for the electricity meters in the later stage is improved.

[0034] Preferably, before generating and sending the device address search instruction, the following steps are further included:

[0035] Obtain the updated electricity meter value according to the specified address, where the updated electricity meter value represents the number of electricity meters increased according to the response feedback signal;

[0036] Judge whether the updated electricity meter value is 0;

[0037] If the updated electricity meter value is 0, add 1 to the preset value, and judge whether the preset value is the specified value, where the specified value represents the lowest value for stopping obtaining the response feedback signal;

[0038] If the preset value is the specified value, it is determined that the regular acquisition of the response feedback signals of each electricity meter ends, and a stop sending signal is generated, where the stop sending signal represents stopping receiving the response feedback signals of each electricity meter, and step S400 is executed; if the preset value is not the specified value, it is determined that the regular acquisition of the response feedback signals of each electricity meter has not ended, and steps S200 - S300 are executed;

[0039] If the updated electricity meter value is not 0, restore the preset value to 0, and repeat steps S200 - S300.

[0040] By adopting the above technical solution, by judging whether the preset value is the specified value, it is further determined whether to stop the addressing operation for the electricity meters. If the preset value is the specified value, a stop sending signal is generated to stop receiving the response feedback signals of each electricity meter, and then the device addresses are sequentially obtained according to the address list set, and the meter reading data is obtained according to the device addresses.

[0041] Preferably, in step S400, after regularly obtaining the response feedback signals of each electric meter, the following steps are further included:

[0042] Obtain a verification signal, and obtain a set of device addresses based on the verification signal;

[0043] Sequentially obtain the device addresses stored in the set of address lists, and match the device addresses in the set of device addresses;

[0044] Determine whether an address corresponding to the device address is matched in the set of device addresses;

[0045] If an address corresponding to the device address is not matched in the set of device addresses, then remove the device address from the set of address lists.

[0046] By adopting the above technical solution, the device addresses in the set of address lists are matched in the set of device addresses. If an address corresponding to the device address is not matched in the set of device addresses, then the device address in the set of address lists is removed. When an electric meter is damaged or removed, there is no need for manual removal of the device address corresponding to the electric meter from the set of address lists. Directly compare the elements in the set of device addresses with those in the set of address lists to find the device addresses that appear in the set of address lists but do not appear in the set of device addresses, and automatically remove the electric meters corresponding to these device addresses in the set of address lists, reducing manual operations and improving the acquisition efficiency of electric meter data.

[0047] In a second aspect, the present application provides a meter reading system based on dynamic device addresses, adopting the following technical solution: A meter reading system based on dynamic device addresses executes the meter reading method based on dynamic device addresses described in the first aspect.

[0048] In a third aspect, the present application provides a storage medium, adopting the following technical solution:

[0049] A storage medium stores at least one instruction, at least one program, a code set or an instruction set, and the at least one instruction, the at least one program, the code set or the instruction set is loaded and executed by a processor to execute the meter reading method based on dynamic device addresses described in the first aspect.

[0050] Through the meter reading method, system and medium based on dynamic device addresses provided by the embodiments of the present application, by obtaining the device addresses of electric meters and eliminating the same addresses in all device addresses, an address list set is obtained. Then, the response feedback signals of the electric meters are regularly obtained, and the obtained device addresses are matched in the address list set. If no match is found, a specified address different from the address list set is generated and stored in the address list set. Through multiple matches, electric meters with the same device address can be distinguished. Thus, after regularly obtaining the response feedback signals of each electric meter, a data acquisition signal is obtained, and the electric meter data is obtained based on the device address according to the data acquisition signal, and the data of each electric meter in the address list set can be recorded more accurately; after distinguishing the electric meters with the same device address, the device addresses are obtained based on the address list set, and the corresponding feedback times are obtained. A time list containing unique times is obtained from the feedback times, and then the time for obtaining the response feedback signals of the electric meters is controlled so that all electric meters pass through the RS-485 bus at different times, thereby improving the accuracy of data acquisition of the RS-485 for electric meters; after distinguishing the electric meters with the same device address, the device addresses are obtained based on the address list set, and the corresponding feedback times are obtained. A time list containing unique times is obtained from the feedback times, and then the time for obtaining the response feedback signals of the electric meters is controlled so that all electric meters pass through the RS-485 bus at different times, thereby improving the accuracy of data acquisition of the RS-485 for electric meters; the device addresses in the address list set are matched in the device address set. If no address corresponding to the device address is found in the device address set, the device address in the address list set is eliminated. When an electric meter is damaged or removed, there is no need to manually eliminate the device address corresponding to the electric meter from the address list set. By directly comparing the elements in the device address set and the address list set, the device addresses that appear in the address list set and do not appear in the device address set are found, and the electric meters corresponding to the device addresses are automatically eliminated in the address list set, reducing manual operations and improving the efficiency of obtaining electric meter data. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 is a block diagram of a meter reading method based on dynamic device addresses;

[0052] Figure 2 is a schematic diagram of the addressing and meter reading processes of the prior art solution;

[0053] Figure 3 is a schematic diagram of the remote addressing and meter reading processes provided by the embodiments of the present application;

[0054] Figure 4 is a block diagram of obtaining an address list set provided by the embodiments of the present application;

[0055] Figure 5 It is the specific addressing for obtaining the set of address lists and the schematic diagram of meter reading;

[0056] Figure 6 It is the addressing and meter reading schematic diagram after adding an electric meter provided by the embodiment of the present application;

[0057] Figure 7 It is the schematic diagram of the steps after removing an electric meter provided by the embodiment of the present application;

[0058] Figure 8 It is the addressing and meter reading schematic diagram after removing an electric meter provided by the embodiment of the present application. Specific embodiments

[0059] To more clearly understand the purpose, technical solution, and advantages of the present application, the present application will be described and explained below with reference to the accompanying drawings and embodiments. However, those of ordinary skill in the art should understand that the present application can be implemented without these details. In some cases, in order to avoid unnecessary description from obscuring various aspects of the present application, well-known methods, processes, systems, components, and / or circuits that have been described at a higher level will not be elaborated further. For those of ordinary skill in the art, it is obvious that various changes can be made to the disclosed embodiments of the present application, and without departing from the principles and scope of the present application, the general principles defined in the present application can be applied to other embodiments and application scenarios. Therefore, the present application is not limited to the illustrated embodiments, but conforms to the broadest scope consistent with the scope claimed in the present application.

[0060] The embodiment of the present application discloses a meter reading method based on dynamic device addresses, which is applied to a meter reading system with dynamic device addresses. The meter reading system with dynamic device addresses includes a concentrator and a master station system network-connected to the concentrator. The concentrator is installed in the monitoring area where electric meters are concentrated. All electric meters in this area are connected to the concentrator through the RS-485 interface, and then the concentrator transmits the data to the master station system, thereby realizing meter reading for this monitoring area.

[0061] It should be noted here that the meter reading system with dynamic device addresses specifically adopts a meter reading system that supports a multi-in-one interface, which can manage multiple electric meters on one platform and perform data collection. The concentrator installed in the area transmits the electric meter readings to the master station system so that the master station system can store, process, and analyze the electric meter data. It can mainly perform remote meter reading for multiple electric meters in the monitoring area, including the collection and storage of data such as real-time electricity consumption, power consumption, power, and voltage, and can also provide various functions such as visualization.

[0062] As Figure 1 shown, the meter reading method based on dynamic device addresses includes the following steps:

[0063] S100. Obtain the first feedback signal of each electricity meter, and eliminate the same addresses among all device addresses to obtain a set of address lists.

[0064] Among them, the first feedback signal represents the signal sent by the electricity meter received by the concentrator. The first feedback signal includes at least the device address, which is the factory default device address in the electricity meter. The device addresses included in the set of address lists are all different from each other.

[0065] Specifically, to obtain the first feedback signal of each electricity meter, the specific steps are as follows: According to the concentrator, send a broadcast frame for searching the device address to all the electricity meters corresponding to it. The electricity meters corresponding to the concentrator will all receive the broadcast frame for searching the device address and respond to the broadcast frame for searching the device address by sending the first feedback signal to the concentrator. It should be noted here that all the electricity meters corresponding to the concentrator will receive the broadcast frame for searching the device address and respond, mainly because it is default that all the electricity meters corresponding to the concentrator are in a normal communication state. If a certain electricity meter is damaged, it means that this electricity meter will not receive the broadcast frame for searching the device address either. Therefore, the electricity meters corresponding to the concentrator here refer to the electricity meters that can communicate normally, rather than all the electricity meters.

[0066] Therefore, after the concentrator is powered on and after the concentrator sends the broadcast frame for searching the device address, the concentrator obtains the first feedback signal of each electricity meter. After the concentrator receives the first feedback signal of each electricity meter, it will process according to the device address corresponding to each first feedback signal, eliminate the same addresses among all the device addresses, and then store the remaining device addresses in the set of address lists. The device addresses in this set of address lists are all different from each other.

[0067] It should be noted here that since not all the electricity meters corresponding to the concentrator can respond to the broadcast frame for searching the device address and send the first feedback signal, the first feedback signal received by the concentrator is the signal sent by most or all of the electricity meters.

[0068] Specifically, the steps to determine whether the concentrator has received the first feedback signal of some electricity meters are as follows: After the concentrator is powered on, it sends a broadcast frame for searching the device address to all the electricity meters connected to it, and uses a preset time as the countdown. When the countdown ends, it is determined that the concentrator has obtained the first feedback signal of some electricity meters.

[0069] The preset time here is set in advance. It mainly refers to the interval time between the concentrator powering on and sending the device address search broadcast frame for the first time and sending it again. As long as the preset time can ensure that all the electricity meters corresponding to the concentrator respond to the device address search broadcast frame and enable the concentrator to receive the first feedback signals from some electricity meters. The preset time is specifically calculated based on the number of electricity meters corresponding to the concentrator and set in advance. The specific setting method is to obtain the data sending time and the number of electricity meters, accumulate the sending times corresponding to all the electricity meters, and then obtain the preset time.

[0070] Here, it should be noted that the data sending time is basically fixed. It is sent at a baud rate of 9600, and it takes about 1 ms to transmit 1 byte. The electricity meter replies to the device address search broadcast frame sent by the concentrator with 28 bytes. Therefore, the time for an electricity meter to send the first feedback signal to the concentrator is about 28 ms. Assuming that the reply time of each electricity meter is 5 times the data sending time, accumulate the reply times of each electricity meter, and then obtain the preset time.

[0071] Exemplarily, assume that the concentrator A corresponds to electricity meters 1, 2, 3, and 4, and the data reply time corresponding to each of electricity meters 1 - 4 is 140 ms. Since the 4 electricity meters altogether take 560 ms, the preset time is set to 560 ms at this time.

[0072] S200, regularly obtain the response feedback signals of each electricity meter, and sequentially match the device addresses in the address list set.

[0073] Among them, the response feedback signal includes the device address corresponding to the electricity meter. The response feedback signal and the first feedback signal are both signals sent by the electricity meter obtained by the concentrator, and the acquisition methods of the response feedback signal and the first feedback signal are both based on that after the concentrator sends the device address search broadcast frame to the electricity meter, the electricity meters connected to the concentrator will send signals to the concentrator after receiving the device address search broadcast frame. Different from the first feedback signal, the response feedback signal is not the signal received after the concentrator powers on. The response feedback signal is the signal received by the concentrator after the concentrator sends the device address search broadcast frame to its corresponding electricity meter again after receiving the first feedback signal corresponding to the electricity meter.

[0074] Regularly obtaining the response feedback signals of each electricity meter includes the following steps:

[0075] S210, obtain the first specified time, and repeat with the first specified time as the countdown.

[0076] S220, when the countdown of the first specified time ends, generate and send a device address search instruction, and receive the response feedback signal according to the device address search instruction.

[0077] Among them, the first specified time represents the interval time for the concentrator to send the broadcast frame for searching the device address each time. This first specified time is the interval time that the concentrator waits at least between sending adjacent broadcast frames for searching the device address. The instruction for searching the device address represents the instruction for the concentrator to send the broadcast frame for searching the device address.

[0078] Specifically, repeat using the first specified time as the countdown. When the countdown of the first specified time ends, the concentrator will resend the instruction for searching the device address once, and then obtain the response feedback signal of the electric meter corresponding to the concentrator according to the instruction for searching the device address. Regularly obtaining the response feedback signal of each electric meter means obtaining it regularly every day, or it can also be obtained every two days. This embodiment does not limit it.

[0079] In actual use, the users corresponding to each community or office building are uncertain. Therefore, the number of electric meters corresponding to the concentrator is also uncertain. If each concentrator uses a fixed first specified time to send the broadcast frame for searching the device address each time, when the number of electric meters corresponding to the concentrator is very small and the interval time between each round of broadcast frames for searching the device address is very large, the concentrator will spend more time to complete the addressing. If there are many electric meters and the first specified time for sending the instruction for searching the device address in each round is small, the electric meters corresponding to the concentrator will not have enough time to respond to the instruction for searching the device address. Either all the electric meters will send response data to the concentrator at the same time, which will easily lead to data conflicts between the electric meters. The concentrator may often not receive the device address due to data conflicts, thus spending more time to complete the addressing. Therefore, on-site, according to the on-site electric meter data, the time for the concentrator to send the broadcast frame each time can be set.

[0080] Obtaining the first specified time includes the following steps:

[0081] S211, obtain the number of electric meter devices.

[0082] S212, obtain the first specified time according to the number of electric meter devices and the preset list.

[0083] Specifically, the number of electric meter devices represents the total number of electric meters, and the preset list represents the relationship list between the number of electric meters and the first specified time. Part of the preset list is shown in Table 1.

[0084] Table 1 Preset List

[0085]

[0086] As can be seen from Table 1, for example, the number of electric meter devices corresponding to a certain concentrator is about 50. Matching the number of electric meter devices in the preset list, it is found that the number of electric meter devices is within the number of electric meter networking in the second group in Table 1. Therefore, the obtained first specified time is 14.336 seconds.

[0087] Under normal circumstances, the device address search broadcast frame is sent 3 - 4 times to complete the addressing. If there are 64 meters, the concentrator can obtain the meter numbers and device addresses of all electric meters in about 1 minute. This time consumption is very small and can be ignored for the meter reading time.

[0088] Here, it should be noted that the specific acquisition method of the first specified time in Table 1 is mainly the product of the reference time and the number of reference time corresponding to all electric meters. The reference time represents the basic time for each electric meter to send a response feedback signal in response to the device address search broadcast frame of the concentrator. In this embodiment, the reference time is preferably set to 4 times the data transmission time, but it is not limited to this. The data transmission time is set to 28 ms, and in this embodiment, the reference time of the device address search broadcast frame is preferably set to 112 milliseconds. To reduce the conflict of data transmission between electric meters, the first specified time for waiting for each round of device address search broadcast frame is set to the total reference time, that is, the product of the reference time and the number of reference time corresponding to all electric meters. The number of reference time mainly refers to the number of reference time required for all electric meters to send response feedback signals in response to the concentrator.

[0089] The number of reference time in Table 1 is mainly calculated based on the product of the highest number of electric meters in each group and the specified multiple. The actual specified multiple is variable, but in Table 1, the specified multiple is preferably set to 2, and the number of electric meters is calculated using the highest number of electric meters. In another embodiment, since all electric meters are hung under the same RS - 485 bus, if an electric meter immediately returns its own device address to the concentrator after receiving the device address search broadcast frame, it will cause a bus conflict. Therefore, it is necessary to stipulate when each electric meter will return the device address to the concentrator after receiving the device address search broadcast frame. The time point for each electric meter to reply to the concentrator is a specified multiple of this reference time, and this specified multiple is randomly generated inside the electric meter. In this way, the time for each electric meter to reply to the device address search broadcast frame is staggered, reducing the data conflict. Of course, there may also be two or more electric meters replying at the same time point, but the probability is very low. Even if it occurs, the device addresses of these electric meters can be successfully obtained in the next round of device address search broadcast frame.

[0090] Receiving a response feedback signal according to the device address search instruction includes the following steps:

[0091] S221, randomly obtain the specified multiple corresponding to each electric meter, and the specified multiple is greater than 1.

[0092] S222, take the product of the specified multiple and the preset reference time as the second specified time corresponding to the electric meter.

[0093] S223, use the second specified time as the countdown. When the second specified time ends, according to the device address search instruction and receive the response feedback signal corresponding to each electric meter.

[0094] Among them, the specified multiple represents a value randomly generated inside the electric meter. The second specified time corresponding to the electric meter is mainly obtained by multiplying the specified multiple by the preset reference time. The second specified time represents the time when each electric meter sends a response feedback signal in response to the device address search broadcast frame sent by the concentrator. The preset reference time is the basic time for each electric meter to send a response feedback signal in response to the device address search broadcast frame of the concentrator, which is set in advance. In this embodiment, the preset basic time is preferably set to 112 milliseconds.

[0095] It should be noted here that the specified multiple corresponding to each electric meter is randomly obtained. Since the second specified time corresponding to each electric meter is greater than the preset reference time, the specified multiple is a number greater than 1.

[0096] S300, if not matched, obtain the specified address. The specified address is different from all the addresses in the address list set. Take the specified address as the device address corresponding to the electric meter and store it in the address list set.

[0097] Among them, the specified address represents the replacement address generated by the electric meter corresponding to the device address obtained in step S200 by the concentrator. This replacement address is used as the corresponding device address of the current electric meter, and the specified address is different from several device addresses in the address list set.

[0098] S400, after regularly obtaining the response feedback signal of each electric meter, obtain the data acquisition signal, and obtain the electric meter data based on the device address according to the data acquisition signal.

[0099] Among them, the data acquisition signal represents the signal generated by the data generation module inside the concentrator for the concentrator to obtain. The data acquisition signal sent by the data generation module is mainly used to enable the concentrator to obtain the electric meter data. The data acquisition signal includes a timing acquisition signal and a real-time acquisition signal. When the concentrator receives the timing acquisition signal and sends the timing acquisition signal to the electric meter, the corresponding device addresses in the address list set all receive the timing acquisition signal and respond to the timing acquisition signal to regularly send the electric meter data to the concentrator.

[0100] When the concentrator sends the real-time acquisition signal to the electric meter, the corresponding device addresses in the address list set all receive the real-time acquisition signal and respond to the real-time acquisition signal to send the electric meter data to the concentrator in real time.

[0101] It should be noted here that the timing acquisition signal can set the sending interval in advance, and the sending interval can be determined according to the actual situation. For example, the sending interval can be set to 5 minutes. At this time, the electricity meters corresponding to each device address send electricity meter data to the concentrator regularly every 5 minutes, but it is not limited to this.

[0102] When the concentrator sends a real-time acquisition signal to the electricity meter, each electricity meter will send the electricity meter data to the concentrator in real time. There will also be a corresponding real-time sending interval for real-time sending, but the real-time sending interval is relatively short, so it is equivalent to the electricity meter sending the electricity meter data to the concentrator in real time.

[0103] If the concentrator is always in the process of addressing the electricity meter and does not read the meter in time, it will cause the master station system to be unable to obtain the electricity meter data in time, thus affecting the reading of the electricity meter data. Therefore, in order not to affect the reading of the electricity meter data, the concentrator will send a broadcast frame for searching for device addresses regularly every day, and the number of daily sendings is also limited. Generally, the broadcast frame for searching for device addresses is sent 5 times or 8 times a day, etc. Of course, this number is set according to the actual situation on site.

[0104] In the above step S220, before generating and sending the instruction for searching for the device address, the following steps are also included:

[0105] S230, obtain the updated electricity meter value according to the specified address.

[0106] S240, determine whether the updated electricity meter value is 0.

[0107] S250, if the updated electricity meter value is 0, then add 1 to the preset value and determine whether the preset value is the specified value.

[0108] S260, if the preset value is the specified value, then determine that the periodic acquisition of the response feedback signal from each electricity meter ends, and generate a stop sending signal, and execute step S400.

[0109] S270, if the preset value is not the specified value, then determine that the periodic acquisition of the response feedback signal from each electricity meter has not ended, and execute steps S200 - S300.

[0110] S280, if the updated electricity meter value is not 0, then restore the preset value to 0, and repeat to execute steps S200 - S300.

[0111] Among them, the updated electricity meter value represents the number of electricity meters increased according to the response feedback signal, the specified value represents the lowest value for stopping the acquisition of the response feedback signal, and the stop sending signal represents stopping receiving the response feedback signal from each electricity meter.

[0112] Specifically, since the concentrator needs to read the electricity meter data in real time, if the concentrator sends broadcasts for a long time, it will cause the concentrator to have no extra time to read the meters. Therefore, the concentrator cannot keep sending the device address search broadcast frames. So in the concentrator, it will be judged that if no new device addresses are received for two consecutive times, the concentrator will consider that it has obtained the device addresses of all electricity meters, and there are no newly installed electricity meters below, then it will stop sending the device address search broadcast frames. Of course, this number can be configured according to the situation, and the default is usually two consecutive times. When the concentrator does not receive new device addresses for two consecutive times, it means that the concentrator has stored the device addresses of all corresponding electricity meters in the address list set, and then the meter reading work can be carried out.

[0113] For the existing remote meter reading system, if the device addresses of more than two electricity meters under the concentrator are the same, manual replacement of the electricity meters is required to solve the problem that meter reading cannot be performed due to device address conflicts.

[0114] As Figure 2 shown, first install the concentrator and the electricity meters corresponding to the concentrator, and then pre-store the device addresses of all electricity meters corresponding to the concentrator in the concentrator. The concentrator reads each electricity meter in turn according to the device address. Suppose the device address corresponding to electricity meter 1 is 0x0015, the device address corresponding to electricity meter 2 is 0x0016, and the device address corresponding to electricity meter 3 is 0x0016. The concentrator sends request data frames to each electricity meter in turn. After the electricity meter receives the request data frame, it judges whether the device address in the concentrator's request data frame is the same as its own address. If they are the same, it prepares the data and returns the data to the concentrator. If they are not the same, it does not respond to the request data frame sent by the concentrator.

[0115] Exemplarily, first the concentrator reads electricity meter 1. By judging that the device address in the concentrator's request data frame is the same as its own address, electricity meter 1 prepares the data and returns the data to the concentrator. Electricity meter 2 judges that the device address in the concentrator's request data frame is not the same as its own address, and electricity meter 2 does not respond to the request frame. Electricity meter 3 judges that the device address in the concentrator's request data frame is not the same as its own address, and electricity meter 3 does not respond to the request frame.

[0116] Next, the concentrator reads the electricity meter 2. Since the electricity meter 1 determines that the device address in the request data frame of the concentrator is inconsistent with its own address, the electricity meter 1 does not respond to the request data frame sent by the concentrator. The electricity meter 2 determines that the device address in the request data frame of the concentrator is consistent with its own address. The electricity meter 2 prepares data and replies to the concentrator. The electricity meter 3 determines that the device address in the request data frame of the concentrator is consistent with its own address. The electricity meter 3 prepares data and replies to the concentrator. However, since the device addresses of the electricity meter 2 and the electricity meter 3 are the same, the electricity meter 2 and the electricity meter 3 will reply to the concentrator with data simultaneously, which will cause a data conflict on the RS-485 bus and prevent the concentrator from reading data. In the existing solution, the staff will remove the electricity meter 3 and install a new electricity meter 4, and the device address corresponding to the electricity meter 4 is 0x0017.

[0117] Finally, read the electricity meter 1, the electricity meter 2, and the electricity meter 4 in sequence. The electricity meter 1, the electricity meter 2, and the electricity meter 4 send their own data to the concentrator in sequence according to the above judgment.

[0118] For this embodiment, if there are more than two electricity meters with the same device address under the concentrator, there is no need for manual replacement of the electricity meter. The concentrator can solve the problem of unable to read the meter caused by the device address conflict through more than 2 re-addressings.

[0119] As Figure 3 shown, the device address corresponding to the electricity meter 1 is 0x0015, the device address corresponding to the electricity meter 2 is 0x0016, and the device address corresponding to the electricity meter 3 is 0x0016. The concentrator sends a broadcast frame for searching the device address to obtain the first feedback signal of the electricity meter. After receiving the broadcast frame for searching the device address, the electricity meter sends its corresponding device address to the concentrator.

[0120] Exemplarily, first, the electricity meter 1 responds to the broadcast frame for searching the device address and sends the device address 0x0015 to the concentrator. The electricity meter 2 responds to the broadcast frame for searching the device address and sends the device address 0x0016 to the concentrator. The electricity meter 3 responds to the broadcast frame for searching the device address and sends the device address 0x0016 to the concentrator. The concentrator discards the device address 0x0016 by receiving two identical device addresses. At this time, the obtained address list set includes the device address 0x0015.

[0121] Next, the concentrator sends a device address search broadcast frame again to obtain the response feedback signal corresponding to the electricity meter. After receiving the device address search broadcast frame, the device address corresponding to Meter 1 is within the address list set, so Meter 1 does not respond. After receiving the device address search broadcast frame, the device address corresponding to Meter 2 is not within the address list set, so a new device address 0x0017 is generated and sent to the concentrator. After receiving the device address search broadcast frame, the device address corresponding to Meter 3 is not within the address list set, so a new device address 0x0018 is generated and sent to the concentrator.

[0122] In another embodiment, since all the electricity meters corresponding to the concentrator are hung under the same RS-485 bus and RS-485 is a half-duplex shared medium, if the concentrator receives the first feedback signals sent by different electricity meters at the same time, multiple electricity meters will be able to receive the data sent by other electricity meters, which will cause a conflict on the bus. Therefore, different from the response feedback signal, the first feedback signal also includes the feedback time, and the feedback time is in one-to-one correspondence with the device address.

[0123] Combined with Figure 4 , obtaining the address list set includes the following steps:

[0124] S110, obtain all device addresses in the address list set.

[0125] S120, obtain the time list according to the feedback time corresponding to the device address.

[0126] S130, use the time list set as the new address list set.

[0127] Among them, the time list contains unique times, and the unique times are characterized as feedback times without duplicate times. Specifically, first, obtain all non-repeating device addresses in the address list set, then among all non-repeating device addresses, eliminate the electricity meters that send data at the same time, and remove the device addresses corresponding to these electricity meters from the address list set, thus obtaining a new address list set.

[0128] Combined with Figure 5 , specifically, the device address corresponding to Meter 1 is 0x0015, the device address corresponding to Meter 2 is 0x0016, and the device address corresponding to Meter 3 is 0x0017. The concentrator sends a device address search broadcast frame to obtain the first feedback signal of the electricity meter. After receiving the device address search broadcast frame, the electricity meter sends its corresponding device address to the concentrator.

[0129] First, the electricity meter 1 responds to the device address search broadcast frame and sends the device address 0x0015 to the concentrator. The electricity meter 2 responds to the device address search broadcast frame and sends the device address 0x0016 to the concentrator. The electricity meter 3 responds to the device address search broadcast frame and sends the device address 0x0017 to the concentrator. The concentrator receives the device addresses corresponding to two electricity meters simultaneously. Since it will affect the transmission of RS-486 bus data, the concentrator discards the device addresses received at the same time. At this time, the set element of the obtained address list is 0x0015.

[0130] Next, the concentrator sends the device address search broadcast frame again to obtain the response feedback signal of the electricity meter. After receiving the device address search broadcast frame, the device address of the electricity meter 1 is in the address list set, so the electricity meter 1 does not respond. After receiving the device address search broadcast frame, the device address of the electricity meter 2 is not in the address list set, so a new device address 0x0017 is generated and sent to the concentrator. After receiving the device address search broadcast frame, the device address of the electricity meter 3 is not in the address list set, so a new device address 0x0018 is generated and sent to the concentrator.

[0131] If, during use, one or more new electricity meters are added under a certain concentrator, after the installation of the electricity meters, the existing technical solution requires manual configuration of the meter numbers of the new electricity meters into the concentrator, and then the concentrator will read the data of the newly connected electricity meters. If there is a conflict between the device address and the original device address, the electricity meter needs to be replaced again.

[0132] In another embodiment, if, during use, one or more new electricity meters are added under a certain concentrator, after the installation of the electricity meters, there is no need to manually configure the meter numbers of the new electricity meters into the concentrator because the concentrator sends the device address search broadcast frame regularly every day. If new electricity meters are installed, the concentrator can quickly address the device addresses of the new electricity meters, and then the concentrator can read the data of the newly added electricity meters. Even if there is a conflict between the device address and the original device address, it can be resolved by re-addressing without having to replace the electricity meter again.

[0133] Combined with Figure 6 , when the concentrator powers on every day, it starts to send the device address search broadcast frame to obtain the first feedback signal of the electricity meter. The electricity meter 1 receives the device address search broadcast frame and sends its corresponding device address 0x0015 to the concentrator. The electricity meter 2 receives the device address search broadcast frame and sends its corresponding device address 0x0016 to the concentrator. Therefore, the formed address list set includes the device address 0x0015 and the device address 0x0016.

[0134] Then the concentrator will read the meters according to the device addresses in the address list set, and then judge whether the device address currently read by the concentrator is the same as its own address through the meter, so as to select whether to transmit data.

[0135] Since the concentrator sends a broadcast frame for searching device addresses regularly every day, when a new meter is installed on the concentrator, it can be judged whether a new meter is added to the concentrator by judging whether the received device address exists in the address list set.

[0136] As Figure 6 shown, when it is found that the device address returned by the received Meter 4 is 0x0018 and it is not found in the address list set, it is determined that a new meter is added to the concentrator, and then the device address can be stored in the address list set. If one or more meters are removed under a certain concentrator during use, after the meters are removed, the corresponding meter numbers in the concentrator need to be manually deleted, and then the concentrator will not read the data of the removed meters. In another embodiment, if the meters corresponding to a certain concentrator are reduced during use, after the meters are disassembled, there is no need to manually remove the meter numbers corresponding to the meters from the address list set of the concentrator. Instead, through the addressing process between the concentrator and the meters, the meters will be automatically reduced in the address list set of the concentrator.

[0137] Combined with Figure 7 , after regularly obtaining the response feedback signals of each meter in step S400, the following steps are further included:

[0138] S510, obtain a verification signal and obtain a device address set according to the verification signal.

[0139] S520, sequentially obtain the device addresses stored in the address list set and match the device addresses in the device address set.

[0140] S530, judge whether an address corresponding to the device address is matched in the device address set.

[0141] S540, if an address corresponding to the device address is not matched in the device address set, remove the device address from the address list set.

[0142] Among them, the verification signal represents the signal for the concentrator to send an address verification broadcast frame to the meter. The concentrator obtains the signal sent by its internal data generation module. The verification signal sent by the data generation module is mainly used to make the concentrator send an address verification broadcast frame to the meter.

[0143] The device address set indicates that after receiving the address verification broadcast frame, the meter will respond to the address verification broadcast frame and send its corresponding device address to the concentrator, thereby forming a device address set. The "after the response feedback signal of each meter is obtained regularly" mentioned here means after the concentrator sends the device address search broadcast frame multiple times every day.

[0144] It should be noted here that the device address corresponding to the meter in response to the address verification broadcast frame refers to the device address in the address list set obtained in steps S100-S300, not the initial device address corresponding to the meter. After the meter obtains the corresponding device address through steps S100-S300, a communication error or removal may occur, and the meter cannot respond to the address verification broadcast frame, and then the device address set is compared with the device address in the address list set to find the device address that appears in the address list set but does not appear in the device address set, and the meter corresponding to the device address in the address list set is automatically removed, thereby reducing manual operations and improving the efficiency of obtaining meter data. If one or more meters are removed from a concentrator during use, after the meters are removed, there is no need to manually delete the corresponding meter number in the concentrator, because the concentrator will send an address verification broadcast frame regularly every day. If a meter is removed, the concentrator cannot address the device address of the meter, and then the concentrator will delete the device address corresponding to the meter, and will not read the data of the meter next time, thus avoiding the waste of time and resources.

[0145] Combination Figure 8 , the concentrator starts sending a device address search broadcast frame every day when it is powered on to obtain the first feedback signal from the meter. Meter 1 receives the device address search broadcast frame and sends its corresponding device address 0x0015 to the concentrator. Meter 2 receives the device address search broadcast frame and sends its corresponding device address 0x0016 to the concentrator. Meter 3 receives the device address search broadcast frame and sends its corresponding device address 0x0017 to the concentrator. Therefore, the address list set formed includes device address 0x0015, device address 0x0016 and device address 0x0017.

[0146] After the concentrator obtains the response feedback signal of each meter on a regular basis every day, it will periodically send an address verification broadcast frame. Therefore, it is determined whether the meter corresponding to the concentrator has been removed or has a communication fault by judging whether the device address sent by the meter in response to the address verification broadcast frame exists in the address list set. If it exists in the address list set, the meter corresponding to the concentrator has not been removed or has a communication fault. If it does not exist in the address list set, the meter corresponding to the concentrator has been removed or has a communication fault.

[0147] Finally, the concentrator will read each meter according to the device address in the address list set. The meter then determines whether data needs to be transmitted by judging whether the device address currently read by the concentrator is consistent with its own address.

[0148] like Figure 8 As shown, the concentrator sends a verification broadcast frame at regular intervals every day, and meter 1 returns the device address 0x0015, and meter 2 returns the device address 0x0016. Through verification, it is found that the concentrator does not receive the device address 0x0017 corresponding to meter 3, so the concentrator assumes that meter 3 has been removed or the communication fails, and deletes the device address corresponding to meter 3 from the address list set.

[0149] In addition, it can be used more flexibly. After the concentrator is powered on, after the first device address broadcast frame is sent for addressing, the waiting time for sending the device address broadcast frame can be dynamically adjusted according to the number of valid device addresses received by the concentrator.

[0150] After obtaining the first designated time according to the number of electric meter devices and the preset list, the following steps are also included:

[0151] S213, obtaining the first electricity meter number according to the address list set.

[0152] S214, obtaining a replacement time according to the first number of electricity meters and a preset list, and using the replacement time as a first designated time.

[0153] The first electricity meter quantity represents the quantity of electricity meters first stored in the address list set, and the replacement time represents the time obtained based on the first electricity meter quantity.

[0154] For example, assume that the first specified time is initially set to 14.336 seconds, and then the first round of device address broadcast frames are sent to receive the first feedback signal. As a result, only the device addresses of more than ten meters are received in the address list set. At this time, the concentrator believes that the number of meters below is not large, and the waiting time for sending device address broadcast frames can be reduced in the next round. According to the data in Table 1, it can be changed from 14.336 seconds to 7.168 seconds, thereby shortening the time to complete device addressing.

[0155] It should be noted here that since the address list set only receives meters with unique device addresses and at the feedback time, the number of meters received by the concentrator may subsequently be inconsistent with the actual number received. However, since the meters with the same device address and the same feedback time are only a minority after all, the difference between the number of meters obtained from the address list set and the number of meters received at the time can be ignored here.

[0156] The implementation principle is:

[0157] After the concentrator sends a broadcast frame for searching for device addresses to the electricity meters, each electricity meter corresponding to the concentrator will receive the broadcast frame for searching for device addresses and respond to the broadcast frame for searching for device addresses by sending a first feedback signal to the concentrator. Therefore, after the concentrator is powered on and after the concentrator sends a broadcast frame for searching for device addresses, the concentrator obtains the first feedback signal of each electricity meter. After the concentrator receives the first feedback signal of each electricity meter, it will process according to the device address corresponding to each first feedback signal, eliminate the same addresses among all the device addresses, and then store the remaining device addresses in the address list set.

[0158] Repeat with the first specified time as the countdown. When the countdown of the first specified time ends, the concentrator will resend a command for searching for device addresses, and then obtain the response feedback signal of the electricity meters corresponding to the concentrator according to the command for searching for device addresses, and match the device addresses in the address list set in turn. If no match is found, a specified address is obtained. The specified address is different from the addresses in the address list set. The specified address is used as the device address corresponding to the electricity meter and is stored in the address list set. After regularly obtaining the response feedback signal of each electricity meter ends, a data acquisition signal is obtained, and electricity meter data is obtained based on the device address according to the data acquisition signal.

[0159] The embodiment of the present application also discloses a meter reading system based on dynamic device addresses, which executes a meter reading method based on dynamic device addresses.

[0160] The meter reading system based on dynamic device addresses includes a set acquisition module, a data matching module, an execution module, and a data reading module. The set acquisition module is used to obtain the first feedback signal of each electricity meter. The first feedback signal includes a device address, and the same addresses among all the device addresses are eliminated to obtain an address list set. The data matching module is used to regularly obtain the response feedback signal of each electricity meter. The response feedback signal includes the device address corresponding to the electricity meter, and the device addresses are matched in the address list set in turn. If no match is found, the execution module is used to obtain a specified address. The specified address is different from the addresses in the address list set. The specified address is used as the device address corresponding to the electricity meter and is stored in the address list set. The data reading module is used to obtain a data acquisition signal after regularly obtaining the response feedback signal of each electricity meter ends, and obtain electricity meter data based on the device address according to the data acquisition signal.

[0161] The other functions executed by the above set acquisition module, data matching module, execution module, and data reading module, as well as the technical details of each function, are the same as or similar to the corresponding features in the meter reading method based on dynamic device addresses described above, so they will not be repeated here.

[0162] The embodiments of the present application also disclose a storage medium storing at least one instruction, at least one program, a code set or an instruction set, which is loaded and executed by a processor to implement a meter reading method based on a dynamic device address.

[0163] It should be understood that although the steps in the flowchart of the accompanying drawings are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise clearly stated in this article, there is no strict order restriction for the execution of these steps, and they may be executed in other orders.

[0164] The above are all the preferred embodiments of the present application, and do not limit the protection scope of the present application accordingly. Therefore, all equivalent changes made according to the structure, shape and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A meter reading method based on a dynamic device address, characterized in that, Including the following steps: Step S100, obtaining the first feedback signal of each electricity meter, where the first feedback signal includes a device address, and eliminating the same addresses among all the device addresses to obtain an address list set; Step S200, regularly obtaining the response feedback signal of each electricity meter, where the response feedback signal includes the device address corresponding to the electricity meter, and sequentially matching the device address in the address list set; Step S300, if no match is found, obtaining a specified address, where the specified address is different from all the addresses in the address list set, using the specified address as the device address corresponding to the electricity meter, and storing it in the address list set; Step S400, after regularly obtaining the response feedback signal of each electricity meter ends, obtaining a data acquisition signal, and obtaining electricity meter data based on the device address according to the data acquisition signal; Among them, the first feedback signal further includes a feedback time, and the feedback time and the device address are in one-to-one correspondence. Among them, obtaining the address list set includes the following steps: Obtaining all the device addresses in the address list set; Obtaining a time list according to the feedback time corresponding to the device address, where the time list contains a unique time, and the unique time represents a feedback time without duplicate times; Using the time list as a new address list set.

2. The meter reading method based on a dynamic device address according to claim 1, characterized in that, The regularly obtaining the response feedback signal of each electricity meter includes the following steps: Obtaining a first specified time, and repeating with the first specified time as the countdown; When the countdown of the first specified time ends, generating and sending a device address search instruction, and receiving a response feedback signal according to the device address search instruction.

3. The meter reading method based on a dynamic device address according to claim 2, characterized in that, The obtaining the first specified time includes the following steps, Obtaining the number of electricity meter devices, where the number of electricity meter devices represents the total number of electricity meters; Obtaining the first specified time according to the number of electricity meter devices and a preset list, where the preset list represents a relationship list between the number of electricity meters and the first specified time.

4. The meter reading method based on a dynamic device address according to claim 2, characterized in that, The receiving the response feedback signal according to the device address search instruction includes the following steps, Randomly obtaining a specified multiple corresponding to each electricity meter, where the specified multiple is greater than 1; Taking the product of the specified multiple and a preset reference time as the second specified time corresponding to the electricity meter; Using the second specified time as the countdown, and when the second specified time ends, receiving the response feedback signal corresponding to each electricity meter according to the device address search instruction.

5. The meter reading method based on a dynamic device address according to claim 3, characterized in that, After obtaining the first specified time according to the number of electricity meter devices and the preset list, it also Includes the following steps, Obtaining the number of first electricity meters according to the address list set, where the number of first electricity meters represents the number of electricity meters first stored in the address list set; Obtaining a replacement time according to the number of first electricity meters and the preset list, and using the replacement time as the first specified time.

6. The meter reading method based on a dynamic device address according to claim 2, characterized in that, Before generating and sending the device address search instruction, it also includes the following steps: Obtaining an updated electricity meter value according to the specified address, where the updated electricity meter value represents the number of electricity meters increased according to the response feedback signal; Judging whether the updated electricity meter value is 0; If the updated electricity meter value is 0, increment the preset value by 1, and determine whether the preset value is the specified value, where the specified value represents the lowest value for stopping the acquisition of the response feedback signal; If the preset value is the specified value, determine that the periodic acquisition of the response feedback signal for each electricity meter ends, and generate a stop sending signal, where the stop sending signal represents stopping the reception of the response feedback signal for each electricity meter, and execute step S400; If the preset value is not the specified value, determine that the periodic acquisition of the response feedback signal for each electricity meter has not ended, and execute steps S200 - S300; If the updated electricity meter value is not 0, reset the preset value to 0, and repeat the execution of steps S200 - S300.

7. The meter reading method based on a dynamic device address according to claim 1, characterized in that, In step S400, after the periodic acquisition of the response feedback signal for each electricity meter ends, the following steps are further included: Obtain a verification signal, and obtain a set of device addresses based on the verification signal; Sequentially obtain the device addresses stored in the address list set, and match the device addresses in the set of device addresses; Determine whether an address corresponding to the device address is matched in the set of device addresses; If an address corresponding to the device address is not matched in the set of device addresses, remove the device address from the address list set.

8. A meter reading system based on a dynamic device address, characterized in that, Execute the meter reading method based on dynamic device addresses according to any one of claims 1 - 7.

9. A storage medium, characterized in that, The storage medium stores at least one instruction, at least one program, a code set or an instruction set, and the at least one instruction, the at least one program, the code set or the instruction set are loaded and executed by a processor to execute the meter reading method based on dynamic device addresses according to any one of claims 1 - 7.

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