JP7397735B2 - Radio field strength measuring device - Google Patents

Description

The present invention relates to a radio field strength measuring device for measuring radio field strength when acquiring power information such as current, electric power, and electric energy required for operational control of distributed power supply equipment through wireless communication. be.

(Existing equipment)

In addition to commercial power sources, homes equipped with so-called distributed power sources, such as solar power generation, storage batteries, cogeneration systems that generate electricity using gas engines and fuel cells, and utilize waste heat, may experience overcurrent or reverse power flow. It is important to monitor such matters. For example, a distributed power source such as a cogeneration system is connected to a control system of a distributed power source such as a cogeneration system by attaching a clamp-type current sensor or the like to the distribution board of the house, and through wiring work that penetrates the wall of the house. By connecting it, it was common to monitor overcurrent, reverse power flow, etc.

By the way, if it is possible to directly acquire data on the power usage status of a house from a smart meter, or indirectly from a home controller such as a HEMS (Home Energy Management System), it is possible to Although it is possible to omit the work of attaching the type current sensor to a distribution board or the like and the work of wiring penetrating the wall of a house, this has not been realized yet.

Note that smart meter information acquisition has communication paths of A route, B route, and C route.

Route A is a communication route that connects the smart meter and the power company, route B is a communication route that connects the smart meter and HEMS, etc., and route C is the communication route that connects the smart meter and HEMS, etc., and route C is the communication route that connects the smart meter and the power company. This is a communication route for providing information to three parties (retail electricity companies, etc.).

As a reference regarding smart meters, Patent Document 1 provides a distribution board that can prevent enlargement even when it accommodates equipment that manages both power consumption data of branch power lines and power amount data from smart meters. Are listed.

More specifically, Patent Document 1 describes a main breaker, a plurality of branch breakers connected to the main bar, a current sensor unit that measures the current flowing through each branch breaker, and a current sensor unit installed at a site adjacent to the branch breaker. and a power information transmitting unit equipped with a power information output section that receives branch current information measured by the current sensor unit, calculates and outputs power usage for each branch circuit, and the power information transmitting unit is connected to the main bar. between the smart meter installed on the primary side of the main breaker via the connected main bar and G3-PLC (Power Line Communication) or Wi-SUN (Wireless Smart Utility Network). B-route communication is performed in one of the communications, and in addition to the power amount data obtained through the communication, the power consumption data of the branch electric line obtained from the current sensor unit is output to the outside.

In addition, as a conventional technology described in Patent Document 1, a power information transmission unit installed in a distribution board performs B route communication with a smart meter using either G3-PLC or Wi-SUN wireless communication. , there is no description of the relationship between the power information transmission unit and the distributed power sources.

In addition, as prior art related to improving wireless communication in houses, Patent Document 2 discloses that it is difficult or impossible to send and receive radio waves for smart meters, radio waves for Wi-Fi signals, or radio waves such as Bluetooth (registered trademark). A communication cable that runs from a communication difficult place to a good communication place where it is easy to transmit and receive radio waves, and an antenna that is connected to each end of the communication cable and can transmit and receive the radio waves, and the communication cable is equipped with a smart meter. An indoor wireless system is described that connects the outdoors where the HEMS is installed and a room in which a HEMS is installed, and runs from the outdoors to the room.

Japanese Patent Application Publication No. 2014-075895 JP2019-009698A

However, the control system of a distributed power source such as a cogeneration system acquires power information directly from a smart meter via route B, or from a smart meter to a HEMS via route B, and then from the HEMS to a specified low-power wireless If it is assumed that power information will be acquired indirectly through wireless communication, various problems may arise due to wireless communication.

For example, if a smart meter is installed near the entrance or open hallway of an apartment complex, etc., and a distributed power source such as a cogeneration system (including a control system) is installed on the balcony side across the space of the house, the structure of the house Walls and furniture (regardless of whether they are electrical appliances or wooden products) weaken the radio wave strength of communication between the smart meter and the control system of a distributed power source such as a cogeneration system, causing communication to fail. Sometimes.

For example, even in a detached house, even if a smart meter and a cogeneration system (including a control system) are installed on each of a pair of walls that are parallel to each other with an indoor space in between, the communication The shortest distance is the path that passes through the house, and just like in an apartment complex, the walls and furniture (regardless of electrical appliances or wooden products) that make up the house are connected to smart meters and distributed power supply control systems such as cogeneration systems. This may weaken the radio wave strength of communication between the device and cause communication to fail.

Furthermore, when installing a distributed power source such as a cogeneration system, we measure the strength of radio waves and determine the optimal installation location so that radio waves can be received from smart meters or HEMS, or radio waves can be sent to smart meters or HEMS. However, in order to communicate with a smart meter or HEMS (Wi-SUN, G3PLC, specified low power wireless, etc.), it is necessary to (e.g. obtaining the necessary information), and currently the procedure can take up to two weeks, making it difficult to respond quickly.

The present invention measures the strength of radio waves and prevents radio interference in wireless communications when information is transmitted and received by wireless communication between control devices that manage the energy used in a house, in situations where wireless communication procedures have not been established. The purpose is to obtain a radio field strength measuring device that can provide an optimal installation positional relationship of a control device by predicting the occurrence of radio wave intensity.

The radio field strength measuring device according to the present invention is arranged near a first position where a power information transmitting device that outputs power information of a specific house is installed, and is configured to detect a specific frequency band of radio waves transmitted by the power information transmitting device. A transmitting device that emits radio waves in a frequency band and radio field intensity equivalent to the radio field intensity, and a second location where the distributed power source of the specific house is installed or planned to be installed, and transmitting from the transmitting device. is capable of receiving radio waves, and includes a display unit that determines and reports the state of the received radio waves by determining whether or not the radio wave strength is at a predetermined level between at least the first position and the second position. It has a receiving device.

According to the present invention, the transmitting device is disposed in the vicinity of a first position where a power information transmitting device that outputs power information of a specific house is installed, and the transmitting device is arranged in the vicinity of a first position where a power information transmitting device that outputs power information of a specific house is installed, Transmits radio waves with the same frequency band and radio field strength as the radio field strength.

On the other hand, the receiving device is placed near a second location where the distributed power source of the specific house is installed or planned to be installed, and is capable of receiving radio waves transmitted from the transmitting device. The receiving device includes a display unit that determines and reports the state of the received radio waves, at least between the first position and the second position, by determining whether or not the radio field strength is a predetermined value. , can recognize radio field strength through vision.

The radio field intensity measurement device according to the present invention is placed near a first location where a smart meter that outputs power information of a specific house is installed, and has a radio field intensity equivalent to the B route frequency band and radio field intensity emitted by the smart meter. A transmitting device that transmits radio waves in a frequency band and radio field strength, and a second location where the distributed power source of the specific house is installed or planned to be installed, and receives the radio waves transmitted from the transmitting device. a receiving device equipped with a display unit that determines whether or not the strength of the received radio waves is at a predetermined strength between at least a first position and a second position and notifies the state of the received radio waves; have.

According to the present invention, the transmitting device is placed near a first location where a smart meter that outputs power information of a specific house is installed, and has a frequency band equivalent to the B route frequency band and radio wave intensity transmitted by the smart meter. Transmits radio waves in the frequency band and radio field strength.

On the other hand, the receiving device is placed near a second location where the distributed power source of the specific house is installed or planned to be installed, and is capable of receiving radio waves transmitted from the transmitting device. The receiving device includes a display unit that determines and reports the state of the received radio waves, at least between the first position and the second position, by determining whether or not the radio field strength is a predetermined value. , can recognize radio field strength through vision.

In the present invention, the receiving device is likened to a repeater that can relay radio waves from the transmitting device and retransmit it to a distributed power source, and the receiving device is arranged at a plurality of positions inside the specific house. The present invention is characterized in that the transmitting device transmits radio waves and the receiving device receives radio waves.

When installing a repeater, the optimal installation position can be visually recognized.

In the present invention, the distributed power source is a fuel cell cogeneration system including a power generation section that generates power using gas and a hot water generation section that generates hot water using heat generated during power generation. It is characterized by

When installing a fuel cell cogeneration system, it is possible to secure an optimal installation position.

According to the present invention, when transmitting and receiving information by wireless communication between control devices that manage energy used in a house, in a situation where wireless communication procedures have not been established, the radio wave intensity is measured and the radio wave of the wireless communication is By predicting the occurrence of a failure, it is possible to provide an optimal installation positional relationship for the control device.

1 is a schematic diagram of a cogeneration device according to an embodiment of the present invention and a house in which the cogeneration device is installed. It is a control block diagram of the controller of a cogeneration device. It is a transition characteristic diagram of the amount of electricity used, the amount of hot water stored in a tank, the amount of hot water used, and the amount of gas used based on living conditions (daily lifestyle). (A) is a plan view showing the positional relationship between a smart meter and a cogeneration device in an apartment complex, and (B) is a plan view showing the positional relationship between a smart meter and a cogeneration device in a detached house. FIG. 1 is a schematic diagram of a house showing a state before installing a cogeneration device according to the present embodiment. FIG. 2 is a front view of the receiving device of the radio field strength measuring device according to the present embodiment, in which (A) is a screen during radio field strength measurement, and (B) is a screen for searching for the optimum installation location for a repeater. It is a schematic diagram of a cogeneration device according to a modification and a house in which the cogeneration device is installed (equipped with HEMS).

FIG. 1 shows a schematic diagram of a household fuel cell cogeneration system (hereinafter simply referred to as "cogeneration system 10" in this embodiment) as an example of distributed power supply equipment according to the present embodiment. has been done.

The cogeneration device 10 is a system that includes a tank unit and a fuel cell unit. Note that coexisting does not mean that they are physically adjacent, but rather that they cooperate with each other. That is, the tank unit and the fuel cell unit may be installed separately and connected by piping, electrical wiring, or the like.

As shown in FIG. 1, the cogeneration device 10 is installed along the outer wall of a house 12, and a worker goes to the site and performs the installation work.

FIG. 1 shows a state in which the installation work has been completed, the test run has been completed, and the system can be operated steadily in cooperation with various equipment (electrical equipment, hot water supply equipment, etc.) on the house 12 side.

(Configuration of cogeneration device 10)

Although not shown, the cogeneration device 10 includes a hot module, a power conditioner, an exhaust heat recovery device, a heat storage tank, a radiator, a heat exchanger, etc., each of which is controlled by a controller 14 to control a hot water supply related control section 27 and a power generation device. They are controlled in cooperation with each other via the related control section 29 (see FIG. 2).

The hot module uses a fuel processing device to extract hydrogen, supplies the extracted hydrogen to the fuel cell stack, and generates DC power using oxygen in the air.

A power conditioner converts the generated DC power into AC power and supplies it to a house.

The exhaust heat recovery device recovers heat from exhaust heat gas generated by power generation.

A heat storage tank can store heat recovered via a heating medium at high temperatures, and the stored heat is used when hot water is supplied.

A radiator causes a heat medium to radiate heat. A radiator is not required.

The heat exchanger uses the high temperature heat medium from the heat medium tank to heat the tap water. A heat exchanger is not required.

Further, the cogeneration device 10 can also send the generated power to the heat source device 16 via the power line 15. The heat source device 16 further heats the hot water heated by the cogeneration device 10 by burning city gas (for example, 13A) as needed, and supplies the heated water to the house 12.

As shown in FIG. 2, the controller 14 includes a microcomputer 28 composed of a CPU 18, a RAM 20, a ROM 22, an I/O 24, and a bus 26 such as a data bus or a control bus that connects these.

A hot water supply related control section 27 and a power generation related control section 29 are connected to the I/O 24, and operations associated with hot water supply and power generation are controlled by the controller 14.

A large-scale storage device 30 is also connected to the I/O 24, which stores processing programs related to power generation and hot water supply executed by the controller 14, as well as history information based on power generation (for example, in this embodiment, , communication interval adjustment information, etc.) are stored.

Furthermore, a remote control 32 is connected to the I/O 24. The remote control 32 is installed inside the house 12 where the cogeneration device 10 is installed, and has a function for the user to input commands regarding the cogeneration device 10 (and the heat source device 16), and displays the status of the cogeneration device 10. It has functions such as

(Distributed power source configuration)

As shown in FIG. 1, in the distributed power source according to the present embodiment, the power generated by the commercial power source 34 and the cogeneration device 10 is used as the power source for the house 12.

Commercial power source 34 is connected to smart meter 36 . The smart meter 36 measures electric power information such as the current, electric power, and electric energy of the commercial power source 34, and transmits the measured information to a specific communication destination through the communication paths of route A, route B, and route C. Is possible.

That is, the A route is a communication path that connects the smart meter 36 and the electric power company, and the B route is a communication path that connects the smart meter 36 and the equipment installed in the house 12 (for example, if a HEMS is constructed, its controller, etc. ), and the C route is a communication route for providing data acquired by the power company via the A route to a third party (retail power company, etc.).

A power line 38 output from the smart meter 36 is wired to a distribution board 40 installed inside the house 12.

In the distribution board 40, assuming that the smart meter 36 side is the upstream side, a service breaker 42, an earth leakage breaker 46, and a safety breaker 48 are installed in this order from the upstream side.

The service breaker 42 is a circuit breaker for determining contract capacity, but may not be installed.

The earth leakage breaker 46 is a circuit breaker that quickly senses and interrupts earth leakage in the internal wiring and electrical equipment of the house 12 to prevent electrical accidents.

The safety breaker 48 is attached to each of the branch circuits for transmitting power from the distribution board 40 to each usage location of the house 12, and is automatically activated when a short circuit or power usage exceeding a certain level is detected due to a failure of electrical equipment, etc. It is a circuit breaker that protects the circuit.

Here, the power generated by the cogeneration device 10 is combined with the commercial power source 34 via a dedicated safety breaker 48A provided in the distribution board 40, and is used as a power source for electrical equipment inside the house 12. I can do it.

Although not shown in the drawings, the cogeneration device 10 is provided with a power line dedicated to when the commercial power source 34 is out of power, so that the power generated by the cogeneration device 10 can be switched on when power is not supplied from the commercial power source 34 due to a power outage. , can be supplied through a power outage dedicated outlet installed in a part of the house 12.

Here, the controller 14 of the cogeneration device 10 needs to control the generated power according to the amount of power used in the house 12, which changes from moment to moment.

As an example, FIG. 3 shows a transition characteristic diagram of power usage, tank hot water storage volume, hot water supply usage, and gas usage based on living conditions (daily lifestyle). In FIG. 3, as an example, it is assumed that the rated power generation output of the cogeneration device 10 is 0.7kW, and if the power consumption in the house 12 is 0.7kW or less, the power consumption in the house 12 is only the power generation output. When the power exceeds 0.7 kW, control is shown in which the power is supplied by the generated power and the commercial power supply 34. Therefore, the controller 14 uses the B route communication path from the smart meter 36 to obtain power information such as the current, power, and amount of power of the commercial power source 34.

In this embodiment, the interval at which power information is acquired from the smart meter 36 via the B route communication path is set to once every 30 seconds. With this interval, it is possible to roughly follow the ever-changing power usage in the house 12 without violating various wireless communication standards, and to perform control approximating the power transition characteristics shown in FIG. 3.

By the way, the smart meter 36 is in a fixed position and basically cannot be moved. For this reason, there are restrictions on the installation location of the cogeneration device 10 (the controller 14 thereof) where wireless communication with the smart meter 36 is required. In other words, the cogeneration device 10 needs to be installed at an optimal position where the radio wave intensity of communication via the B route communication path from the smart meter 36 can continue to be at a predetermined intensity or higher. There were two major hurdles in installing the machine in the optimal position.

One of the obstacles is that it is difficult to secure radio wave strength (hereinafter referred to as "failure 1"), and the other obstacle is that a procedure is required for wireless communication with the smart meter 36, but the procedure There are cases where a prompt response cannot be taken because it takes time to respond (hereinafter referred to as "Failure 2").

(Obstacle 1)

One of the factors that weakens the radio field strength is the presence of obstacles such as walls that constitute the house 12.

FIG. 4(A) is a plan view showing the positional relationship between the smart meter 36 and the cogeneration device 10 in the housing complex 12A.

In the housing complex 12A, a smart meter 36 is generally installed on the entrance 50 side. On the other hand, when installing the cogeneration device 10 in the housing complex 12A, it may be installed on the balcony 52 side. In such an installation relationship between the smart meter 36 and the cogeneration device 10, the indoor walls 54 and furniture 56 (regardless of electric appliances, wooden products, etc.) of the apartment complex 12A are connected to the smart meter 36 and the cogeneration device 10. This may cause the strength of radio waves for communication with the controller 14 to be weakened.

Next, FIG. 4(B) is a plan view showing the positional relationship between the smart meter 36 and the cogeneration device 10 in the detached house 12B.

In the detached house 12B, the smart meter 36 is attached to an outer wall 58, and the cogeneration device 10 is installed along the outer wall 60 on the opposite side that is parallel to the outer wall 58 and the inner space of the detached house 12B. may be done.

In such an installation relationship between the smart meter 36 and the cogeneration device 10, the outer walls 58 and 60, the inner wall 61, and the furniture 63 (regardless of electric appliances, wooden products, etc.) of the detached house 12B are connected to the smart meter 36. This may cause a weakening of the radio field strength of communication between the cogeneration device 10 and the controller 14.

(Obstacle 2)

In order to eliminate obstacle 1, before installing cogeneration device 10, it is only necessary to determine the optimal position where a predetermined radio field intensity can be maintained.

However, in order to receive information wirelessly from the smart meter 36 via the communication route B before installing the cogeneration device 10, certain procedures (obtaining an ID (identification code), PW (password), etc.) are required. In addition, as the procedure currently takes up to two weeks, it may be difficult to respond quickly.

Therefore, in this embodiment, as shown in FIG. 5, a radio field strength measuring device 66 is used as a preparation device for installing the cogeneration device 10 at a stage before installing the cogeneration device 10. The configuration is such that the radio wave intensity can be measured before the generation device 10 is installed.

As shown in FIG. 5, the radio field strength measuring device 66 includes a transmitting device 68 and a receiving device 70.

The transmitting device 68 is attached near the smart meter 36, and the receiving device 70 is placed at the location where the cogeneration device 10 is planned to be installed.

In this state, the transmitting device 68 transmits radio waves with the same radio frequency band and radio field strength as the B route. The receiving device 70 can receive radio waves from the transmitting device 68 (that is, pseudo radio waves based on the B route communication path of the smart meter 36). That is, by appropriately changing the relative positional relationship between the transmitting device 68 and the receiving device 70, it is possible to obtain a positional relationship that eliminates the problem 1. Note that the transmitting device 68 may have a function that can adjust the message content and message length of communication as necessary.

On the other hand, since the transmitting device 68 transmits radio waves with the radio frequency and radio field strength of the pseudo B route communication route instead of the smart meter 36, the transmitting device 68 becomes a substitute device for the B route communication of the smart meter 36. , it becomes possible to eliminate obstacle 2.

The operation of this embodiment will be explained below.

As shown in FIG. 5, the cogeneration device 10 has not yet been installed in the house 12, and the procedures for acquiring power information through the B route communication path of the smart meter 36 have not yet been completed.

Therefore, without considering the radio field strength, there is a possibility that a situation may arise in which it is not possible to obtain power information from the smart meter 36 by wireless communication after the cogeneration device 10 is installed.

When such a situation occurs, conventionally, as additional work, for example, a clamp-type current sensor (not shown) is attached to the distribution board 40, and the wiring is passed through the outer wall of the house 12 to the cogeneration device 10. There was a need.

In contrast, in the present embodiment, before installing the cogeneration device 10, the transmitting device 68 of the radio field strength measuring device 66 is installed near the smart meter 36, and the receiving device 70 is installed at a candidate location for installing the cogeneration device 10. The transmitter 68 transmits pseudo radio waves based on the B route communication path of the smart meter 36.

A location where the receiving device 70 can receive this pseudo radio wave becomes a location where the cogeneration device 10 can be installed.

(Inspection procedure)

As shown in FIG. 6(A), the receiving device 70 is provided with a monitor 71. The monitor 71 has a gauge section 74 that can display the radio field intensity in stages (0 to 10 stages in FIG. 6A), and the display on the gauge section 74 changes depending on the received radio field strength. Radio field strength can be displayed in stages. Therefore, the person inspecting the radio field strength can visually grasp the radio field strength (by looking at the state of the gauge section 74). Note that the monitor 71 may be a display unit using a light source such as an LED.

Note that an OK threshold line 75 is displayed superimposed on the gauge section 74, and the radio field intensity index value determined by the gauge section 74 is higher than this OK threshold line 75 (in this embodiment, the level 6 or higher), the radio field strength is determined to be valid.

As a countermeasure in case the radio wave intensity does not exceed the OK threshold line 75 when the receiving device 70 receives the radio waves from the transmitting device 68 in FIG. 6(A), a repeater may be installed in the house. In this case, the receiving device 70 can display the repeater optimum installation location candidate 76 by switching the monitor 71, as shown in FIG. 6(B).

When an inspector carries the receiving device 70 of this embodiment and moves around a house with this repeater optimum installation location candidate 76 displayed, marks 72 with different radio wave intensities are displayed on coordinate axes that resemble the house. be done.

For example, in FIG. 6(B), it is assumed that the radio wave intensity is high in the order of triangular mark 72A→circle mark 72B→star mark 72C. The inspector can determine the installation location of the repeater by looking at the arrangement of the marks 72.

(Modified example)

The controller 14 of the cogeneration device 10 according to the present embodiment is based on the premise that power information is acquired directly from the smart meter 36 installed in the house 12 via route B.

Here, as shown in FIG. 7, a HEMS 62 is constructed in the house 12 according to the modified example.

The HEMS 62 saves electricity and gas used in the house 12 by managing it in real time, and also helps prevent global warming by reducing carbon dioxide.

By connecting home appliances and the like to the HEMS controller 64 built into the HEMS 62 and managing the usage status of electricity and gas on a monitor, visualization (monitor display) is realized and the home appliances are automatically controlled.

By the way, the HEMS 62 acquires data that is the basis of management from the smart meter 36. In other words, the HEMS controller 64 of the HEMS 62 has acquired the same power information as the smart meter 36.

Therefore, in the modified example, between the controller 14 of the cogeneration device 10 and the HEMS controller 64 of the HEMS 62, Wi-SUN HAN, Wi-SUN Enhanced HAN, specified low power wireless, LPWA (Low Power Wide Area), etc. On the premise that a communication protocol is established using a communication means and power information is acquired from the HEMS controller 64 of the HEMS 62, the transmitting device 68 of the radio field strength measuring device 66 is placed near the HEMS 62.

The transmitting device 68 transmits radio waves in the LPWA radio frequency band and radio wave intensity equivalent to the HEMS controller 64 of the HEMS 62, and the radio waves are received by the receiving device 70 placed in the installation candidate of the cogeneration device 10. The optimal placement position of the generation device 10 can be recognized.

Note that in this embodiment, a distributed power source is realized by combining the commercial power source 34 and the cogeneration device 10, but the combination of the distributed power source is not limited to the commercial power source 34 and the cogeneration device 10. , geothermal power generation, wind power generation, storage batteries, etc., the present invention is applicable to all configurations in which power information is acquired from the smart meter 36 etc. and the amount of power generation is controlled.

10 Cogeneration device 12 House 12A Apartment house 12B Single-family house 14 Controller 15 Power line 16 Heat source machine 18 CPU
20 RAM
22 ROM
24 I/O
26 Bus 27 Hot water supply related control unit 28 Microcomputer 29 Power generation related control unit 30 Large scale storage device 32 Remote control 34 Commercial power supply 36 Smart meter 38 Power line 40 Distribution board 42 Service breaker 46 Earth leakage breaker 48 Safety breaker 48A Safety breaker 50 Entrance 52 Balcony 54 Wall 56 Furniture 58 External wall 60 External wall 61 Internal wall 62 HEMS
63 Furniture 64 HEMS controller 66 Radio field strength measuring device 68 Transmitting device 70 Receiving device 71 Monitor 72 Mark 72A Triangle mark 72B Circle mark 72C Star mark 74 Gauge section 75 OK threshold line 76 Optimum repeater installation location candidate

Claims (4)

A frequency band and radio field intensity that are placed in the vicinity of a first location where a power information transmitting device that outputs power information of a specific house is installed, and that are equivalent to the specific frequency band and radio field strength of the radio waves transmitted by the power information transmitting device. a transmitting device that transmits radio waves;
a receiving device that is capable of receiving radio waves transmitted from the transmitting device, and includes a display unit that determines whether the state of the received radio waves is at a predetermined radio field intensity and notifies the user;
The receiving device is capable of receiving at least radio waves transmitted from the transmitting device when the distributed power source of the specific house is installed or is placed near a second location where it is planned to be installed.
Radio field strength measuring device. It is placed near the first location where a smart meter that outputs power information of a specific house is installed, and transmits radio waves in the same frequency band and radio field strength as the B route frequency band and radio field strength transmitted by the smart meter. a transmitting device;
a receiving device that is capable of receiving radio waves transmitted from the transmitting device, and includes a display unit that determines whether the state of the received radio waves is at a predetermined radio field intensity and notifies the user;
The receiving device is capable of receiving at least radio waves transmitted from the transmitting device when the distributed power source of the specific house is installed or is placed near a second location where it is planned to be installed.
Radio field strength measuring device. The receiving device is likened to a repeater that can relay the radio waves from the transmitting device and retransmit it to the distributed power source,
The radio field intensity measurement according to claim 1 or 2, wherein the transmitting device transmits radio waves and the receiving device receives radio waves with the receiving device arranged at a plurality of positions inside the specific house. Device. The distributed power source is
Any one of claims 1 to 3, wherein the fuel cell cogeneration system is provided with a power generation unit that generates power using gas and a hot water generation unit that generates hot water using heat generated during power generation. The radio field intensity measuring device according to item 1.