CN210534230U

CN210534230U - Non-invasive load monitoring device and terminal

Info

Publication number: CN210534230U
Application number: CN201921269295.7U
Authority: CN
Inventors: 李云峰; 刘三丰
Original assignee: Wuhan Zhongyuan Electronic Information Co ltd
Current assignee: Wuhan Zhongyuan Electronic Information Co ltd
Priority date: 2019-08-06
Filing date: 2019-08-06
Publication date: 2020-05-15
Anticipated expiration: 2029-08-06

Abstract

The application provides a non-invasive load monitoring device and a terminal, wherein the device comprises an ADC (analog to digital converter) acquisition module, a load monitoring module and a load monitoring module, wherein the ADC acquisition module is used for acquiring a voltage signal and a current signal of a line to be detected and converting the voltage signal and the current signal into corresponding digital signals; a local memory for storing the digital signal; the power supply module is used for supplying power; the power supply monitoring module is used for monitoring the power supply module and sending an interrupt signal when the power supply module is interrupted; the microprocessor is used for sending the digital signal to the local memory for storage according to the interrupt signal; a communication module for transmitting the digital signal; the input end of the ADC acquisition module is connected with the tested circuit, and the output end of the ADC acquisition module is connected with the microprocessor; the input end of the power supply module is connected with a tested circuit, and the output end of the power supply module is connected with the microprocessor through the power supply monitoring module; the microprocessor is also connected with the communication module and the local memory respectively.

Description

Non-invasive load monitoring device and terminal

Technical Field

The application relates to the field of load monitoring of power systems, in particular to a non-invasive load monitoring device and a terminal.

Background

At present, the user electrical load monitoring technology at home and abroad can be mainly divided into an invasive type and a non-invasive type, the non-invasive type load monitoring device is favored by domestic and foreign enterprises and college research institutions by virtue of the advantages of convenient installation, easy maintenance and the like, but the existing non-invasive type load monitoring device has the problem that the data acquired by equipment is easy to lose when the device is suddenly powered off in the data acquisition and monitoring process.

SUMMERY OF THE UTILITY MODEL

An object of the embodiments of the present application is to provide a non-invasive load monitoring device and a terminal, so as to solve the problem that collected data of the existing non-invasive load monitoring device is easily lost when power is suddenly turned off.

In order to achieve the above object, the present application provides the following technical solutions:

in a first aspect: the application provides a non-invasive load monitoring device, which is an ADC acquisition module used for acquiring voltage signals and current signals of a tested line and converting the voltage signals and the current signals into corresponding digital signals; a local memory for storing the digital signal; the power supply module is used for supplying power; the power supply monitoring module is used for monitoring the power supply module and sending an interrupt signal when the power supply module is interrupted; the microprocessor is used for sending the digital signal to the local memory for storage according to the interrupt signal; a communication module for transmitting the digital signal; the input end of the ADC acquisition module is connected with a tested circuit, and the output end of the ADC acquisition module is connected with the microprocessor; the input end of the power supply module is connected with the tested circuit, and the output end of the power supply module is connected with the microprocessor through the power supply monitoring module; the microprocessor is also connected with the communication module and the local memory respectively.

The non-invasive load monitoring device of above-mentioned design, through the power supply condition of power monitoring module monitoring power module to produce interrupt signal and send for microprocessor when the outage, microprocessor saves the digital signal who gathers in local memory, makes the device can in time carry out data backup when the outage, can not cause the data loss, and can read the transmission again after the device power supply resumes, has improved data transmission's reliability.

In an optional implementation manner of the first aspect, the power supply monitoring module includes a voltage monitoring chip, a first resistor, a second resistor, a third resistor, a fourth resistor, a capacitor, and a backup power supply; the type of the voltage monitoring chip is MIC 2778; the LTH pin of the voltage monitoring chip is connected with the output end of the power supply module through the first resistor and is grounded through the second resistor and the third resistor in sequence; the HTH pin of the voltage monitoring chip is grounded through the third resistor; the VDD pin of the voltage monitoring chip is connected with the standby power supply and is grounded through the capacitor; the RST pin of the voltage monitoring chip is connected with the microprocessor and is also connected with the standby power supply through the fourth resistor; and the GND pin of the voltage monitoring chip is grounded.

In the above embodiment, when the voltage provided by the power module disappears, the RST pin of the voltage monitoring chip generates a falling edge signal and transmits the falling edge signal to the microprocessor, and the microprocessor triggers the digital signal storage operation through the falling edge signal, so that the microprocessor can perform the digital signal storage operation in time after the power is off, and the reliability of data is ensured.

In an optional implementation manner of the first aspect, the communication module includes a Wifi communication module and a Zigbee communication module, and the Wifi communication module and the Zigbee communication module are respectively connected to the microprocessor.

In an optional implementation manner of the first aspect, the Zigbee communication module includes a Zigbee chip, the Zigbee chip is of a model of ZM516X, the microprocessor is of a model of AM335x, the microprocessor includes a UART interface, a TXD pin of the UART interface is connected to a RXD pin of the Zigbee chip, and the RXD pin of the UART interface is connected to a TXD pin of the Zigbee chip.

In the above embodiment, the Zigbee module is integrated into the communication network of the smart home, so that the monitoring device communicates with the smart home, and the monitoring device achieves a greater effect.

In an optional implementation manner of the first aspect, the local memory includes a flash memory chip, the microprocessor is in an AM335x model, an I/O0 pin of the flash memory chip is connected to a D0 pin of the microprocessor, an I/O1 pin of the flash memory chip is connected to a D1 pin of the microprocessor, an I/O2 pin of the flash memory chip is connected to a D2 pin of the microprocessor, an I/O3 pin of the flash memory chip is connected to a D3 pin of the microprocessor, an I/O4 pin of the flash memory chip is connected to a D4 pin of the microprocessor, an I/O5 pin of the flash memory chip is connected to a D5 pin of the microprocessor, an I/O6 pin of the flash memory chip is connected to a D6 pin of the microprocessor, and an I/O7 pin of the flash memory chip is connected to a D7 pin of the microprocessor.

In the above embodiment, the data transmission between the data interface of the microprocessor and the flash memory chip enables the digital signal processed by the microprocessor after power failure to be rapidly stored in the flash memory chip.

In an optional implementation manner of the first aspect, the ADC acquisition module includes an ADC sampling chip with a model MAX 11040.

In the above embodiment, the maximum sampling frequency of the MAX11040 chip is as high as 64Ksps, and 4 channels of synchronous sampling are supported, so that the acquisition requirements of a single-phase circuit and a multi-phase circuit can be met, and the adaptability is stronger.

In an optional implementation manner of the first aspect, the power supply module includes a rectifying module and a voltage-dropping module, an input end of the rectifying module is connected to the line under test, and the rectifying module is connected to the power supply monitoring module through the voltage-dropping module.

In the embodiment, the power supply module is directly connected with the tested circuit, so that the tested circuit is used as a power supply, the structure of the load monitoring device is reduced, and the convenience in installation of the monitoring device is ensured.

In an alternative embodiment of the first aspect, the device further comprises an indicator light for indicating an operational condition of the device, the indicator light being connected to the microprocessor.

In the above embodiment, the operation state of the monitoring device is intuitively indicated through the indicator lamp, which brings great convenience to the debugging and maintenance work of the monitoring device.

In an alternative embodiment of the first aspect, the line under test is a 220V home circuit.

In a second aspect: the present application provides a non-intrusive load monitoring terminal, which includes a non-intrusive load monitoring apparatus as in any optional implementation manner of the first aspect.

The non-invasive load monitoring terminal of above-mentioned design, through the power supply condition of power monitoring module monitoring power module to produce interrupt signal and send for microprocessor when the outage, microprocessor saves the digital signal who gathers in local memory, makes the device can in time carry out data backup when the outage, can not cause the data loss, and can read the transmission again after the device power supply resumes, has improved data transmission's reliability.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments of the present application will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that those skilled in the art can also obtain other related drawings based on the drawings without inventive efforts.

Fig. 1 is a first schematic view of a non-intrusive load monitoring apparatus according to a first embodiment of the present application;

fig. 2 is a block diagram of a power monitoring module according to a first embodiment of the present disclosure;

FIG. 3 is a second schematic view of a non-intrusive load monitoring apparatus as provided in the first embodiment of the present application;

FIG. 4 is a diagram illustrating a connection between a local memory and a microprocessor according to a first embodiment of the present application;

fig. 5 is a third schematic view of a non-invasive load monitoring apparatus according to a first embodiment of the present application.

Icon: 100-ADC acquisition module; 102-local memory; 1021-a flash memory chip; 104-a power supply module; 1041-a rectification module; 1042-a voltage reduction module; 106-power monitoring module; 1061-voltage monitoring chip; 1062 — a first resistance; 1063-a second resistor; 1064-third resistance; 1065-fourth resistor; 1066-capacitance; 1067-a backup power supply; 108-a microprocessor; 110-a communication module; 1101-a Wifi communication module; 1102-a Zigbee communication module; 112-indicator light.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application.

First embodiment

As shown in fig. 1, the present embodiment provides a non-invasive load monitoring apparatus, which includes an ADC acquisition module 100 for acquiring a voltage signal and a current signal of a line under test and converting the signals into corresponding digital signals; a local memory 102 for storing the digital signal; a power module 104 for supplying power; a power monitoring module 106 for monitoring the power module 104 and sending an interrupt signal when the power module 104 is interrupted; a microprocessor 108 for transmitting the digital signal to the local memory 102 for storage according to the interrupt signal; a communication module 110 for transmitting digital signals;

the input end of the ADC acquisition module 100 is connected with a line to be tested, and the output end of the ADC acquisition module 100 is connected with the microprocessor 108; the input end of the power supply module 104 is connected with a line to be tested, and the output end of the power supply module 104 is connected with the microprocessor 108 through the power supply monitoring module 106; the microprocessor 108 is also connected to the communication module 110 and the local memory 102, respectively.

When the device designed above works normally, the ADC acquisition module 100 is configured to acquire a load signal of a line to be tested, where the load signal includes a voltage signal and a current signal, and transmit a digital signal converted from the load signal to the microprocessor 108, and the microprocessor 108 further processes the acquired digital signal and sends the processed digital signal to a related device for processing. For example, the microprocessor 108 performs filtering, start-stop event detection and other processing on the acquired digital signals, when it is detected that an electrical appliance start-stop event occurs on the detected line, a load feature vector is obtained through calculation and is sent to the internet cloud platform through the communication module 110, and the internet cloud platform calls a load identification algorithm to identify the type and the state of the electrical appliance. In the process, the power module 104 supplies power to the whole system element by converting the voltage on the line to be tested, and the power monitoring module 106 monitors the real-time power supply condition of the power module 104.

If the device suddenly cuts off power in the working process, for example, the power supply module 104 is connected to the tested line and the power is cut off, the power can be cut off. At this time, the power monitoring module 106 detects that the power module 104 is suddenly powered off, generates an interrupt signal, and transmits the interrupt signal to the microprocessor 108, and after receiving the interrupt signal, the microprocessor 108 transmits the acquired digital signal, which is not sent to the internet cloud platform, to the local storage 102 for local storage, and transmits the digital signal through the communication module 110 after the device resumes power supply.

The device of above-mentioned design, through the power supply condition of power monitoring module monitoring power module to produce interrupt signal and send for microprocessor when the outage, microprocessor saves the digital signal of gathering in local memory, makes the device can in time carry out data backup when the outage, can not cause the data loss, and can read the transmission again after the device power supply resumes, has improved data transmission's reliability.

In an optional implementation manner of this embodiment, as shown in fig. 2, the power monitoring module 106 includes a voltage monitoring chip 1061, a first resistor 1062, a second resistor 1063, a third resistor 1064, a fourth resistor 1065, a capacitor 1066, and a standby power supply 1067; the model of the voltage monitoring chip 1061 is MIC2778, and besides the model of MIC2778, the voltage monitoring chip can also be a series of chips with other models; an LTH pin of the voltage monitoring chip 1061 is connected to the output end of the power module 104 through a first resistor 1062, and is further grounded through a second resistor 1063 and a third resistor 1064 in sequence; the HTH pin of the voltage monitoring chip 1061 is grounded through a third resistor 1064; a VDD pin of the voltage monitoring chip 1061 is connected to the standby power supply 1067 and is grounded through a capacitor 1066; the RST pin of the voltage monitoring chip 1061 is connected to the microprocessor 108, and is also connected to the standby power supply 1067 through a fourth resistor 1065; the GND pin of the voltage monitoring chip 1061 is grounded.

In the embodiment of the above design, when the device is powered off, the voltage at the connection between the first resistor 1062 and the power module 104 disappears, and at this time, the voltage monitoring chip 1061 generates a falling edge signal at the RST pin, where the falling edge signal is the aforementioned interrupt signal, and the falling edge signal is transmitted to the microprocessor 108 through the RST pin, and the microprocessor performs the local storage operation of the digital signal after receiving the falling edge signal; when the microprocessor 108 is of the AM335x type, the RST pin of the voltage monitor chip 1061 is connected to the VBAT _ INT pin of the microprocessor 108. In addition, after the power is cut off, since the VDD pin and the RST pin of the power monitoring chip are both connected to the standby power supply 1067, the standby power supply 1067 can supply power to each module in the device for a short time after the power is cut off, so that the microprocessor 108 can complete the storage operation of the digital signals.

In the above embodiment, when the voltage provided by the power module 104 disappears, the RST pin of the voltage monitoring chip 1061 generates a falling edge signal and transmits the falling edge signal to the microprocessor, and the microprocessor triggers the digital signal storage operation through the falling edge signal, so that the microprocessor can perform the digital signal storage operation in time after the power is off, thereby ensuring the reliability of data.

In an alternative embodiment of this embodiment, as shown in fig. 3, the communication module 110 includes a Wifi communication module 1101 and a Zigbee communication module 1102, and both the Wifi communication module 1101 and the Zigbee communication module 1102 are connected to the microprocessor 108.

The Wifi communication module 1101 is configured to send data acquired and processed by the microprocessor 108 to an internet cloud platform, specifically, a chip model of the Wifi communication module 1101 may be WM6201EU, the Wifi communication module 1101 may support two working modes, namely, an STA and an AP, and during an initialization stage of an acquisition terminal, when the Wifi module works in the AP mode, some initialization configuration parameters from the internet cloud platform may be received; and when the monitoring device enters a conventional working stage, the Wifi module works in an STA mode and is responsible for transmitting data to the Internet cloud platform. The communication protocol bottom layer of the Wifi module is based on a TCP/IP protocol stack, and the upper layer is based on an HTTP communication protocol, so that the stability, safety and reliability of data communication of the Wifi module are guaranteed.

The Zigbee communication module 1102 has a main function of integrating the monitoring device into a communication network of an intelligent home, so as to implement a function of communicating with the intelligent home. The Zigbee communication module 1102 includes a Zigbee chip, the Zigbee chip is ZM516X, the microprocessor 108 is AM335x, the microprocessor 108 includes a UART interface, a TXD pin of the UART interface is connected to an RXD pin of the Zigbee chip, and the RXD pin of the UART interface is connected to the TXD pin of the Zigbee chip.

In addition, the Zigbee chip may be a chip of the series of other models, in addition to the model ZM 516X. According to the embodiment, the Zigbee module is integrated into the communication network of the intelligent home, so that the monitoring device is communicated with the intelligent home, and the monitoring device achieves a greater effect.

In an alternative implementation manner of this embodiment, as shown in fig. 4, the local memory 102 includes a flash chip 1021, the model of the microprocessor 108 is AM335x, an I/O0 pin of the flash chip 1021 is connected to a D0 pin of the microprocessor 108, an I/O1 pin of the flash chip 1021 is connected to a D1 pin of the microprocessor 108, an I/O2 pin of the flash chip 1021 is connected to a D2 pin of the microprocessor 108, an I/O3 pin of the flash chip 1021 is connected to a D3 pin of the microprocessor 108, an I/O4 pin of the flash chip 1021 is connected to a D4 pin of the microprocessor 108, an I/O5 pin of the flash chip 1021 is connected to a D5 pin of the microprocessor 108, an I/O6 pin of the flash chip 1021 is connected to a D6 pin of the microprocessor 108, and an I/O7 pin of the flash chip is connected to a D7 pin of.

In the above embodiment, the pins D0 to D7 of the microprocessor 108 are 8-bit wide data interfaces, the flash memory chip 1021 is NandFlash with a capacity of 128MB, when the power is off, the microprocessor 108 transmits the acquired and processed data to the flash memory chip 1021 through the data transmission interfaces of the pins D0 to D7, and when the power supply of the device is restored to normal, the data stored before the power is off can be read out through the data interfaces of the pins D0 to D7, and then the data is sent to the internet cloud platform through the communication module 110.

The foregoing description describes the connection between the flash memory chip 1021 and the microprocessor 108 for data transmission, and includes the connection of the control portion in addition to the connection for data transmission, specifically:

the CLE pin of the flash chip 1021 is connected to the EBL _ A22 pin of the microprocessor 108; the ALE pin of the flash chip 1021 is connected to the EBL _ a21 pin of the microprocessor 108; the RE pin of the flash chip 1021 is connected to the NANDOE pin of the microprocessor 108; the WE pin of the flash chip 1021 is connected to the NANDWE pin of the microprocessor 108.

In an optional implementation manner of this embodiment, the ADC acquisition module 100 may be a chip with a model of MAX 11040. The maximum sampling frequency of the MAX11040 chip is up to 64Ksps, and 4 channels are supported for synchronous sampling, so that the sampling requirements of a single-phase circuit and a multi-phase circuit can be met, and the adaptability is stronger. The load monitoring device using the chip can enable the acquired data to restore the original waveforms of the voltage signal and the current signal on the power bus as high as possible, capture higher harmonics in a transient state stage, facilitate the acquisition of more accurate load characteristic vectors in subsequent steps, and grasp slight differences in load characteristics of the electric appliance, thereby improving the load identification success rate of the whole system.

In an optional implementation manner of this embodiment, as shown in fig. 5, the power module 104 includes a rectifying module 1041 and a voltage-reducing module 1042, an input end of the rectifying module 1041 is connected to the line to be tested, and an output end of the rectifying module 1041 is connected to the power monitoring module 106 through the voltage-reducing module 1042.

The power module 104 is connected to the circuit to be tested, and converts the voltage of the circuit to be tested into the voltage of each module in the device for directly supplying power, the working voltage of each module in the device is generally 1.8V, 3.3V, 5V and the like, the working current is generally direct current, and the circuit to be tested is generally household AC 220V. Therefore, the power module may be provided with a rectifying module 1041 and a voltage-reducing module 1042, the rectifying module 1041 is connected to the circuit to be tested and is configured to convert the alternating current of the circuit to be tested into a direct current, and then transmit the converted direct current to the voltage-reducing module 1042, and the rectifying module 1041 may be a conventional rectifier or rectifying circuit. The voltage-reducing module 1042 then reduces the received dc voltage to a suitable level for powering the device, and may be a conventional voltage-reducing circuit.

In an alternative embodiment of this embodiment, as shown in fig. 5, the apparatus further includes an indicator light 112, where the indicator light 112 is connected to the microprocessor 108 and used for indicating an operation status of the apparatus, after power failure, if the indicator light 112 is still in a bright state, it indicates that the microprocessor 108 is performing data storage after power failure, and if the indicator light 112 is directly turned off after power failure, it indicates that the microprocessor 108 is not performing data storage, and there may be a problem of backup power damage; when the indicator light 112 is illuminated for a period of time after the power is turned off, the microprocessor 108 will have completed storing the data. In addition, a plurality of indicator lights can be arranged and respectively connected with each module in the device for indicating the operation condition of each module.

In the above embodiment, the running state of the monitoring device is intuitively indicated through the indicator lamp, which brings great convenience for the debugging and maintenance work of the monitoring device.

In an alternative embodiment of this embodiment, the microprocessor 108 may be a Cortex-A8 series 32bit ARM processor AM335x with the highest main frequency of 1GHz, which has the advantages of fast processing speed and multiple functions.

Second embodiment

The present application provides a non-intrusive load monitoring terminal comprising a non-intrusive load monitoring device as identified in any of the first embodiments. Since the implementation process is similar to that in the first embodiment, detailed description is omitted here.

In the description of the present application, it should be noted that the terms "inside", "outside", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or orientations or positional relationships that the products of the application usually place when using, and are only used for convenience in describing the present application and simplifying the description, but do not indicate or imply that the devices or elements that are referred to must have a specific orientation, be constructed in a specific orientation, and operate, and thus, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

It should also be noted that, unless expressly stated or limited otherwise, the terms "disposed" and "connected" are to be construed broadly, e.g., as meaning fixedly connected, detachably connected, or integrally connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

The above description is only an example of the present application and is not intended to limit the scope of the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A non-intrusive load monitoring device, comprising: the ADC acquisition module is used for acquiring a voltage signal and a current signal of a tested line and converting the voltage signal and the current signal into corresponding digital signals; a local memory for storing the digital signal; the power supply module is used for supplying power; the power supply monitoring module is used for monitoring the power supply module and sending an interrupt signal when the power supply module is interrupted; the microprocessor is used for sending the digital signal to the local memory for storage according to the interrupt signal; a communication module for transmitting the digital signal;

the input end of the ADC acquisition module is connected with a tested circuit, and the output end of the ADC acquisition module is connected with the microprocessor; the input end of the power supply module is connected with the tested circuit, and the output end of the power supply module is connected with the microprocessor through the power supply monitoring module; the microprocessor is also respectively connected with the communication module and the local memory.

2. The device of claim 1, wherein the power monitoring module comprises a voltage monitoring chip, a first resistor, a second resistor, a third resistor, a fourth resistor, a capacitor, and a backup power supply; the type of the voltage monitoring chip is MIC 2778;

the LTH pin of the voltage monitoring chip is connected with the output end of the power supply module through the first resistor and is grounded through the second resistor and the third resistor in sequence; the HTH pin of the voltage monitoring chip is grounded through the third resistor; the VDD pin of the voltage monitoring chip is connected with the standby power supply and is grounded through the capacitor; the RST pin of the voltage monitoring chip is connected with the microprocessor and is also connected with the standby power supply through the fourth resistor; and the GND pin of the voltage monitoring chip is grounded.

3. The device of claim 1, wherein the communication module comprises a Wifi communication module and a Zigbee communication module, and the Wifi communication module and the Zigbee communication module are respectively connected with the microprocessor.

4. The device as claimed in claim 3, wherein the Zigbee communication module comprises a Zigbee chip having a model of ZM516X, the microprocessor having a model of AM335x, the microprocessor comprising a UART interface, a TXD pin of the UART interface being connected to a RXD pin of the Zigbee chip, and a RXD pin of the UART interface being connected to a TXD pin of the Zigbee chip.

5. The apparatus of claim 1, wherein the local memory comprises a flash memory chip, the model of the microprocessor is AM335x, the I/O0 pin of the flash memory chip is connected with the D0 pin of the microprocessor, the I/O1 pin of the flash chip is connected with the D1 pin of the microprocessor, the I/O2 pin of the flash chip is connected with the D2 pin of the microprocessor, the I/O3 pin of the flash chip is connected with the D3 pin of the microprocessor, the I/O4 pin of the flash chip is connected with the D4 pin of the microprocessor, the I/O5 pin of the flash memory chip is connected with the D5 pin of the microprocessor, the I/O6 pin of the flash memory chip is connected with the D6 pin of the microprocessor, and the I/O7 pin of the flash memory chip is connected with the D7 pin of the microprocessor.

6. The apparatus of claim 1, wherein the ADC acquisition module comprises an ADC sampling chip of model MAX 11040.

7. The device of claim 1, wherein the power module comprises a rectifying module and a voltage-dropping module, an input end of the rectifying module is connected with the tested line, and an output end of the rectifying module is connected with the power monitoring module through the voltage-dropping module.

8. The device of claim 1, further comprising an indicator light for indicating an operating condition of the device, the indicator light being connected to the microprocessor.

9. The apparatus of claim 1, wherein the line under test is an AC220V home circuit.

10. A non-intrusive load monitoring terminal, characterised in that the terminal comprises a non-intrusive load monitoring device as defined in any one of claims 1 to 9.