Electrical installation measurement system

Abstract

The present invention relates to an electrical installation measurement system. An embodiment describes an electrical installation measurement system (100) comprising a control and measurement device (101) configured to be installed on a distribution board (104) of an electrical installation (103) and to perform at least one measurement of an electrical parameter of the electrical installation (103) in function of an electrical load connected to the electrical installation, and to send a command signal (SCM) along a telecommunication link. The system further comprises a variable load device (102) connectable to the electrical installation (103) and configured to: receive said command signal (SCM) from the telecommunication link; and to assume a plurality of load configurations in function of said command signal (SCM).

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a device for measuring electrical parameters of an electrical installation. BACKGROUND

[0002] In low voltage electrical installations, an electrician measures electrical parameters by employing a metering device (e.g. a network analyzer) that can be alternatively connected to different points of the electrical installation. The measurements performed aim at testing the electrical installation to verify whether it complies with certain regulations.

[0003] Document WO2018 / 009932 discloses an electrical network comprising a monitoring device, one or more electrical devices, a network manager and a diagnostic device. The diagnostic device can receive power via a power supply for performing test operations. The diagnostic device can generate a certain level and type of power (referred to herein as a test signal) (e.g. using a transformer, an inverter, a converter, a diode bridge) for testing the one or more electrical devices using the monitoring device.

[0004] Document US2019 / 0261067 describes a system for providing information about electrical devices in a residence, the system comprising a power measurement device, an electrical device identification component, and a notification component. The power measurement device measures characteristics of power in one or more power lines in the residence. Based on power consumption of a particular electrical device, the notification component determines an event or condition (e.g. abnormal usage, device malfunction, excessive power consumption) associated with the particular electrical device. A notification related to at least one of the events or conditions associated with the particular electrical device is provided to a person associated with the residence (e.g. a homeowner or other resident). SUMMARY

[0005] The Applicant has noticed that the metering electrical installation systems currently employed by electricians require complex and time-consuming testing procedures.

[0006] An electrical installation measurement system that makes the testing procedure easier and faster to perform than with the traditional metering devices would meet the needs of professional operators.

[0007] The Applicant has found that, by employing an electrical parameter measurement device that also controls variable load devices electrically connectable to different points of the electrical installation to assume a plurality of load configurations, the complexity and time of the testing procedure can be reduced compared to the traditional techniques.

[0008] According to a first aspect, the present disclosure relates to an electrical installation measurement system comprising:

[0009] A control and measurement device designed to be installed on a distribution board (104) of an electrical installation and configured to: perform at least one measurement of an electrical parameter of the electrical installation as a function of an electrical load connected to the electrical installation; and send a command signal along a telecommunication link;

[0010] A variable load device connectable to the electrical installation and configured to: receive the command signal from the telecommunication link; and assume a plurality of load configurations as a function of the command signal.

[0011] In an embodiment, the variable load device is portable and configured to be electrically connected to the electrical installation to operate as an electrical load of the electrical installation.

[0012] In an embodiment, the variable load device comprises an electrical plug connected to a socket of the electrical installation.

[0013] In an embodiment, the control and measurement device comprises:

[0014] a measurement module configured to perform the at least one measurement of the electrical parameter of the electrical installation;

[0015] a first wireless communication module configured to send the command signal;

[0016] a control and processing device configured to manage the operation of the measurement module and the first wireless communication module.

[0017] In an embodiment, the variable load device comprises:

[0018] a variable impedance module comprising at least one impedance and configured to assume a plurality of values as a function of the plurality of load configurations;

[0019] a second wireless communication module configured to receive the command signal from the first wireless communication module;

[0020] a control device connected to the second wireless communication module and configured to manage the operation of the variable impedance module as a function of the command signal.

[0021] In an embodiment, the at least one impedance is a variable impedance configured to assume a plurality of selectable impedance values as a function of an adjustment signal generated by the control device and as a function of the command signal.

[0022] In an embodiment, the at least one impedance comprises at least one electrical device selected from the group consisting of: a variable resistance load, a variable inductance load, a variable capacitance load, a variable differential current generation circuit.

[0023] In an embodiment, the variable load device comprises:

[0024] at least one output terminal of the electrical installation;

[0025] at least one switching device configured to connect / disconnect the at least one impedance from / to the at least one output terminal according to a switching signal provided by the control device according to the control signal.

[0026] In an embodiment, the control and measurement device is configured to perform the measurement procedure by:

[0027] sending a procedure command signal to cause the variable load device to assume a procedure load configuration when connected to the electrical installation;

[0028] performing the at least one measurement of an electrical parameter of the electrical installation as a function of the procedure load configuration assumed by the variable load device to provide at least one measurement value.

[0029] In an embodiment, the control and measurement device is further configured to process the at least one measurement value to produce at least one calculated electrical parameter.

[0030] In an embodiment, the control and measurement device comprises: a first voltmeter to be connected between a phase conductor and a ground conductor of the electrical installation; a second voltmeter to be connected between a phase conductor and a neutral conductor of the electrical installation; a first ammeter to be connected to the phase conductor; and a second ammeter to be connected to the neutral conductor.

[0031] In an embodiment, the system is configured to perform at least one measurement selected from the group consisting of: measurement of ground return impedance; measurement of voltage drop over a portion of the electrical installation; estimation of short circuit current; test of behavior of a magnetic thermal switch; estimation of differential switch trip current; estimation of differential switch trip time according to the measurement procedure.

[0032] In an embodiment, the system further comprises: at least one computer device external to the control and measurement device and configured to exchange data with the control and measurement device and to store values of electrical parameters; and at least one client device configured to exchange data / information with the control and measurement device and used by a user of the at least one client device to access the stored values.

[0033] In an embodiment, each of the control and measurement device and the variable load device comprises: a respective housing and a respective power supply module.

[0034] In an embodiment, the system is configured to operate on an electrical installation selected from the group consisting of: single-phase electrical installation, three-phase electrical installation. BRIEF DESCRIPTION OF DRAWINGS

[0035] Further characteristics and advantages will become better apparent from the following description of various embodiments, given as an example with reference to the attached drawings wherein:

[0036] Figure 1 An example of an electrical installation measurement system is schematically illustrated;

[0037] Figure 2 An example of a control and measurement device of an electrical installation measurement system is schematically illustrated; Figure 1

[0038] An example of a variable load device of an electrical installation measurement system is schematically illustrated; Figure 3 Figure 2 An embodiment of a control and measurement device of an electrical installation measurement system is schematically illustrated;

[0039] Figure 4 An embodiment of a variable load device of an electrical installation measurement system is schematically illustrated; Figure 2

[0040] An example of a working configuration adopted by an electrical installation measurement system for performing a measurement of an electrical parameter is illustrated; Figure 5

[0041] Reference is made to a further working configuration adopted by an electrical installation measurement system for performing a measurement of a further electrical parameter. Figure 6 DETAILED DESCRIPTION

[0042] Figure 1 An example of an electrical installation measurement system 100 comprising a control and measurement device 101 and a variable load device 102 is illustrated. As shown in Figure 2 The system 100 can further comprise at least one computer device 200 (SRV) configured to provide functionalities to the control and measurement device 101 and to at least one client device, such as, by way of example, a technician device 300 (T-MB) and a user device 301 (U-MB). Figure 1 In particular, the computer device 200 is configured to operate as a server computer for the control and measurement device 101, the user device 301 and / or the technician device 300. According to an example, the computer device 200 can be part of a cloud computing architecture. Each of the technician device 300 and the user device 301 can be, by way of example, a mobile phone (e.g. a smartphone), a laptop, a personal computer.

[0043] The electrical installation measurement system 100 is configured to perform electrical measurements of parameters of an electrical installation (also referred to as “electrical wiring”) 103, such as a domestic wiring for low voltage applications.

[0044]

[0045] ​​​For example, the electrical installation 103 is a single-phase electrical system comprising a phase conductor PC, a neutral conductor NC and a ground conductor GC connected to a grounding system (not shown). By way of example, the electrical installation 103 is configured to operate at a voltage comprised in the range 100-400 V, at a frequency comprised in the range 50-60 Hz.

[0046] According to Figure 1 and Figure 2 By way of example, the electrical installation 103 further comprises an energy provider meter 105 (EPM) connected to the switchboard 104, the switchboard 104 comprising at least one circuit protection device 106. As shown in Figure 2 , the circuit protection device 106 can be a device selected from the group comprising: a circuit breaker 107 (CB), a miniature circuit breaker 108 (MCB), a residual circuit breaker (RCB, not shown) and a residual current circuit breaker with overload protection 109 (RCBO). By way of example, the residual current circuit breaker with overload protection 109 comprises a residual circuit breaker and a magnetothermal switch.

[0047] Furthermore, the electrical installation 103 comprises a junction box (not shown) allowing the phase conductor PC, the neutral conductor NC and the ground conductor GC to be divided into a plurality of secondary circuits SCI-SCN. The junction box can be part of the switchboard 104 and / or can be external to the switchboard 104.

[0048] In particular, the secondary circuits SCI-SCN can be connected to permanently installed electrical loads 110, such as, by way of example, lighting devices controlled by electrical switches 111, or to sockets 112 for connection to portable electrical loads, such as portable electrical appliances, telephones, heating or ventilation system controls.

[0049] The control and measurement device 101 can be configured to be installed in the switchboard 104, for example the control and measurement device 101 is electrically connected between the energy provider meter 105 and the circuit protection device 106 of the switchboard 104 Figure 1 . The control and measurement device 101 is configured to send a command signal SMC Figure 1 to the variable load device 102 and to perform at least one measurement of an electrical parameter of the electrical installation 103.

[0050] The variable load device 102 can be connected to the electrical installation 103. By way of example, the variable load device 102 can be connected to any one of the electrical sockets 112 or other points of the electrical installation 103 by means of connection terminals different from the sockets 112. The variable load device 102 and the control and measurement device 101 can communicate through a telecommunication link. Moreover, the variable load device 102 is configured to receive, via said telecommunication link, a command signal SMC sent by the control and measurement device 101 and to assume a plurality of load configurations according to said command signal.

[0051] Figure 3 An example of the electrical control and measurement device 101 is schematically shown, which comprises a control and processing device 113 (CONTR-PROC) and a measurement module 114.

[0052] By way of example, the control and processing device 113 can be a microprocessor or a microcontroller and comprises one or more control processing units (CPUs) and a memory, including at least one programmable memory M. The memory of the control and processing device 113 stores software containing instructions configured to manage the operation of the control and measurement device 101.

[0053] According to an example, the measurement module 114 comprises a first measurement device 115 and a second measurement device 116. The first measurement device 115 is configured to perform measurements of electrical parameters related to the phase conductor PC and the ground conductor GC, such as, by way of example, phase-to-earth voltage and phase current. In the present example, the first measurement device 115 is provided with a first ammeter 117 connected to the phase conductor PC and a first voltmeter 118 connected between the phase conductor PC and the ground conductor GC.

[0054] According to an example, the second measurement device 116 is configured to perform measurements of electrical parameters related to the phase conductor PC and the neutral conductor NC, such as, by way of example, phase-to-neutral voltage and neutral current. In the present example, the second measurement device 116 is provided with a second ammeter 119 connected to the neutral conductor NC and a second voltmeter 120 connected between the phase conductor PC and the neutral conductor NC.

[0055] Moreover, the measurement module 114 can comprise a first isolator 121 (ISL) configured to electrically isolate the first measurement device 115 from the control and processing device 113. The measurement module 114 can comprise a second isolator 122 (ISL) configured to electrically isolate the second measurement device 116 from the control and processing device 113. The first and second isolators 121, 122 can be, for example, known galvanic isolators or known optical isolators.

[0056] In particular, the control and measurement device 101 is provided with a first power supply device 125. The measurement module 114 can further comprise a third isolator 123 (ISL) and a fourth isolator 124 (ISL), which are similar to the first isolator 121 described above. The third isolator 123 is configured to electrically isolate the first measurement device 115 from the power supply device 125, and the fourth isolator 124 is configured to electrically isolate the second measurement device 116 from the first power supply device 125.

[0057] It is noted that the first measurement device 115, and similarly the second measurement device 116, can be a commercially available energy meter implemented through an integrated circuit. As an example, the energy meter ADE9153A produced by the company Analog Devices Inc. (USA) can be employed. In such an example, the first (second) measurement device 115 (116) is provided with at least one analog-to-digital converter and a digital signal processing device configured to measure a plurality of electrical quantities. Preferably, the first and second measurement devices 115 and 116 can comprise a temperature sensor and a timer.

[0058] The control and measurement device 101 is provided with a first communication means 126, such as a wireless communication means, configured to allow communication with the variable load device 102, and in some embodiments also with additional means external to the measurement device 101. The first communication means 126 is configured to operate under the control of the control and processing device 113 and exchange data with the control and processing device 113 itself.

[0059] In particular, the first communication means 126 comprises a first wireless transceiver module 127 (COMM1) configured to communicate with the variable load device 102. As an example, the first wireless transceiver module 127 operates according to the LoRa (Long Range) technology. As known, LoRa is a Low Power Wide Area Network (LPWAN) technology based on a spread spectrum modulation technique derived from the chirp spread spectrum (CSS) technique.

[0060] The first communication device 126 may further include a second wireless transceiver module 128 (COMM2), which is configured to allow communication with the server computer 200 and the client device 300. Figure 1 As an example, the second wireless transceiver module 128 can operate according to WiFi technology, which allows access to the Internet system 400 to exchange data with the server computer 200 and the client device 300.

[0061] Advantageously, the first communication device 126 may include a third wireless transceiver module 129 (COMM3), which is configured to perform the functions of the second wireless transceiver module 127 when no power supply is available. As an example, the third wireless transceiver module 129 may be configured to operate according to NB-IoT (Narrowband Internet of Things) technology. As is known to those skilled in the art, NB-IoT is a low-power wide-area network (LPWAN) radio technology specifically designed for indoor coverage, low cost, long battery life, and high connection density.

[0062] The aforementioned first power supply device 125 is configured to supply power from electrical facility 103 or from an optional rechargeable battery 130 (e.g., a lithium-ion battery) to the devices / components of control and measurement equipment 1. According to an example, the first power supply device 125 includes a battery charger manager 131 and an AC-to-DC converter 132 configured to convert AC power supplied by electrical facility 103 into DC power.

[0063] The control and measurement equipment 101 is housed in a housing 134, which can be fixed to the distribution panel 104, thereby allowing the aforementioned electrical connection with the electrical facilities 103.

[0064] according to Figure 4 The example shown includes a control device 135 (CONTR-DV), a variable impedance module 136, a second communication module 137, and a second power module 138. Additionally, the variable load device 102 is provided with a plug 139 that can be inserted into a socket 112 of one of the auxiliary circuits SC1-SCN of the electrical facility 103 (e.g., the second auxiliary circuit SC2).

[0065] As an example, control device 135 may be a microprocessor or microcontroller and includes one or more control processing units and memory, including at least one programmable memory. As an example, control device 135 is similar to control and processing device 113 of control and measurement device 101. Control device 135 stores software programs configured to manage the operation of variable impedance module 136 according to command signals SMC received from control and measurement device 101.

[0066] The variable impedance module 136 can assume a plurality of load configurations in dependence of a control signal sent by the control and measurement device 101 and received at the second communication module 137. In particular, the variable impedance module 136 comprises at least one variable impedance that can assume a plurality of values.

[0067] The plug 139 to be inserted into the socket 112 comprises a first terminal 144, a second terminal 145 and a third terminal 146.

[0068] According to an example, the variable impedance module 136 comprises a first adjustable impedance device 140 and a second adjustable impedance device 141. The first adjustable impedance device 140 comprises at least one first variable impedance 142 and a first switch 143. The first variable impedance 142 comprises a terminal connected to the second terminal 145 of the plug 139 and another terminal connected to the first switch 143, which is also connected to the first terminal 144 of the plug 139. The first switch 143 is configured to be closed / opened to connect / disconnect the first variable impedance 142 to / from the first terminal 144.

[0069] The second adjustable impedance device 141 comprises at least one second variable impedance 147 and a second switch 148. The second variable impedance 147 comprises a terminal connected to the third terminal 146 of the plug 139 and another terminal connected to the second switch 148, which is also connected to the first terminal 144 of the plug 139. The second switch 148 is configured to be closed / opened to connect / disconnect the first variable impedance 142 to / from the first terminal 144.

[0070] The first switch 142 and the second switch 147 can assume a closed or an open configuration in dependence of a switching signal SW provided by the control device 135. Each of the first switch 142 and the second switch 147 can be a semiconductor device, such as an IGBT (Insulated Gate Bipolar Transistor), a TRIAC (TRIode for Alternating Current) or a thyristor.

[0071] The first variable impedance 142 and the second variable impedance 147 can assume a plurality of impedance values in dependence of an adjustment signal SA provided by the control device 135. Each of the first variable impedance 142 and the second variable impedance 147 can comprise a device selected from the group consisting of: a variable resistance load, a variable inductance load, a variable capacitance load or a combination thereof.

[0072] As an example, when the plug 139 is inserted into the socket 112, the first adjustable impedance device 140 is electrically connected between the phase conductor PC and the ground conductor GC, and the second adjustable impedance device 141 is electrically connected between the phase conductor PC and the neutral conductor NC.

[0073] The second communication module 137 comprises a wireless transceiver module configured to communicate with the first wireless transceiver module 127 of the control and measurement device 101. According to the described example, the second communication module 137 operates according to LoRa (Long Range) technology.

[0074] The second power supply module 138 is configured to supply the components / modules of the variable load device 102 with the electric power provided by the electrical installation 103 or by another rechargeable battery 149. The second power supply module 138 can comprise another battery charger manager 150.

[0075] It should also be noted that the variable load device 102 is housed in another casing 153 and can be a portable device.

[0076] The electrical installation measurement system 100 (hereinafter referred to as "measurement system") is configured to perform electrical measurements of electrical parameters of the electrical installation 103. In particular, the measurement system 100 is configured to support the electrician in performing the required checks during the testing of a new electrical installation or during its maintenance or periodic control.

[0077] According to possible implementations, the control and measurement device 101 is stably installed on the switchboard 104, while the variable load device 102 is portable and managed by the electrician. For example, depending on the specific test to be carried out, the variable load device 102 can be electrically connected to different sockets 112 of the electrical installation 103 or to specific points of the electrical installation 103 by means of other types of connection terminals. According to an example, the variable load device 102 can be connected to replace one of the electrical loads 110.

[0078] As an example, the technician who performs the tests on the electrical installation 103 adopts a technician mobile phone 300 provided with a corresponding mobile application (APP) to communicate with the control and measurement device 101 and with the server computer 200. The technician can communicate with the control and measurement device 101 to perform specific test procedures that can be selected from the mobile application APP. According to an example, the communication between the control and measurement device 101 and the technician mobile phone 300 is allowed by the second wireless transceiver module 128 Figure 2 ) of the control and measurement device 101. It is also observed that the control and measurement device 101 can store the measured electrical parameters in the server computer 200 and make them available for monitoring purposes.

[0079] With reference to the measurement of the electrical parameters, the control and measurement device 101 and the variable load device 102 operate as "master" and "slave" devices, respectively. In particular, the measurement system 100 allows to perform a measurement procedure that includes a cooperation between the control and measurement device 101 ("master device") and the variable load device 102 (slave device).

[0080] It should be further emphasized that although the following description of specific electrical parameter measurements takes into account the case where the variable load device 102 is connected to the socket 112, a similar description is valid for the connection of the variable load device 102 at a different connection point in the electrical installation 103 than the socket 112.

[0081] The following example of the measurement process is described with reference to the measurement of the voltage drop ΔV across a portion of an electrical facility 103 (with an unknown resistance Rcc) included between control and measurement equipment 101 and a socket 112 in which a variable load device 102 is connected. Also refer to... Figure 5 Describe this example.

[0082] The technician notifies the control and measurement device 101 of the requested measurement by using a technician mobile phone 300. For example, the technician mobile phone 300 communicates with the second wireless transceiver module 128 of the control and measurement device 101. Figure 3 Communication. The control and processing device 113, connected to the second wireless transceiver module 128, sends a corresponding command signal SCM, which is included in the variable load device 102. Figure 4 The second communication module 137 receives the signal. As an example, the control device 135 of the variable load device 102 analyzes the command signal SCM to determine the software portion associated with a specific electrical measurement. Based on the software portion, the control device 135 generates an adjustment signal SA that fixes the resistance value Rn for the second variable impedance 147. The value of the resistance Rn can also be obtained through the control and measurement device 101.

[0083] Furthermore, control device 135 generates a switching signal SW that closes the second switch 148; therefore, a second variable impedance 147 with resistance Rn is connected between the phase conductor PC and the neutral conductor NC. According to this example, the first variable impedance 142 is not connected to electrical facility 103 because it is not involved in any specific measurement process.

[0084] In the above load configuration, the control and measurement device 101 controls the current I flowing in the phase conductor PC. F Measurements were performed, and the voltage V between the phase conductor PC and the neutral conductor NC was measured. FN Measurements are performed. Specifically, the control and processing device 113 enables the first ammeter 117 of the first measuring device 115 to measure the current I. F Furthermore, the control and processing device 113 enables the second voltmeter 120 of the second measuring device 116 to measure voltage V. FN .

[0085] Then, the control and processing device 113 acquires the measured value I. F and VFN and the voltage drop AV is calculated according to the following equation:

[0086] AV = V FN - I F • R n

[0087] The calculated voltage drop AV that can be stored in the memory M of the control and processing device 113 can be transmitted to the server computer 200 from which the voltage drop can be read by the technician mobile phone 300.

[0088] At the end of the measurement, the control and measurement device 101 sends to the variable load device 102 another command signal SCM to cause the second switch 148 to open and the second variable impedance 147 to be disconnected from the plug 139 and the electrical installation 103.

[0089] It is noted that, based on the corresponding load configuration taken by the variable load device 102, the control and measurement device 101 can also perform additional possible measurements of electrical parameters. Examples of such additional measurements are described herein below.

[0090] According to a first example, the control and measurement device 101 can estimate the short-circuit current with the load configuration described above with reference to Figure 5 In particular, the short-circuit resistance Rcc is calculated according to the following equation:

[0091]

[0092] The estimated short-circuit current MaxIcc is calculated as:

[0093]

[0094] According to a second example, the electrical installation measurement system 100 can be used to perform a test on a magnetothermal switch, such as, by way of example, the switch included in the miniature circuit breaker 108 that protects one of the auxiliary circuits SCI-SCN. The estimated short-circuit current MaxIcc is compared with the maximum tripping current I TR of the magnetothermal switch. TR If the maximum tripping current I

[0095] According to the test, the control and measurement device 101 sends to the variable load device 102 a command signal SCM so that the first variable impedance 142 takes a specific resistance value and is connected between the phase conductor PC and the ground conductor GC.

[0096] The control and measurement device 101 monitors, by means of the first ammeter 117, whether the current flowing into the phase conductor PC is interrupted due to the opening of the magnetic thermal switch. If the magnetic thermal switch does not interrupt the current, the test is automatically stopped after a predetermined time interval monitored by a timer device included in the control and measurement device 101.

[0097] According to a second example, the electrical installation measurement system 100 is used to evaluate the differential switch tripping current I dn associated with the residual current circuit breaker 109, as an example. According to this example, the first adjustable impedance device 140 can be driven to operate as a variable differential current generation circuit to generate a variable differential current, which ranges from 0 to 50 mA, with steps of 0.5 mA, or with continuous growth, as an example. The first adjustable impedance device 140 is connected between the phase conductor PC and the ground conductor GC and is controlled to generate the differential current in a way that increases by a predetermined amount (e.g., 0.5 mA) at each time interval T (e.g., T = 50 ms). The value I dn representative of the differential switch tripping current taken by the differential current at the switch of the residual current circuit breaker 109 is measured by the control and measurement device 101.

[0098] The generation of the variable differential current can be obtained, as an example, by means of an IGBT chopper connected to a resistor driven by a PWM (Pulse Width Modulation) signal generated by the control device 135 of the variable load device 102.

[0099] According to a third example, the electrical installation measurement system 100 is used to evaluate the differential switch tripping time of a residual current circuit breaker (such as the miniature circuit breaker 108 or the RCBO 109), also known as differential switch. Consider the value I dn of the differential switch tripping current evaluated as described above, the variable differential current generation circuit controlling the variable load device 102 is controlled to generate the differential current I dn , 2I dn and finally 5I dn .

[0100] In the three cases, the time interval between the initial instant to in which the current I dn , 2I dn or 5I dn is applied and the switching time t1 in which the switch tripping occurs is evaluated by means of a timer (e.g., a high-resolution timer) included in the control and measurement device 101. Preferably, if the differential switch does not open within a maximum time interval (e.g., 100 ms), the test is automatically interrupted by the control and measurement device 101 to avoid overheating. It has been observed that it is advantageous to evaluate the exact breaking time by means of the control and measurement device 101.

[0101] It should also be noted that the first measuring device 115 and the second measuring device 116, included in the measuring module 114 of the control and measuring device 101, can also perform the measurement of the electrical parameters independently of the variable load device 102, i.e. without cooperating with the variable load device 102.

[0102] In particular, the measuring module 114 is configured to perform the measurement of at least one electrical parameter selected from the group consisting of:

[0103] v FT : the phase-to-ground voltage, i.e. the voltage between the phase conductor PC and the ground conductor GC;

[0104] v FN : the phase-to-neutral voltage, i.e. the voltage between the phase conductor PC and the neutral conductor GNC;

[0105] i F : the phase current, i.e. the current flowing into the phase conductor PC;

[0106] i N : the neutral current, i.e. the current flowing into the neutral conductor NC.

[0107] Preferably, for the phase-to-ground voltage v FT , the phase-to-neutral voltage v FN , the phase current i F and the neutral current i N , it is possible to measure the corresponding waveform and the corresponding root mean square (RMS) value: V FT , V FN , I F , I N .

[0108] In addition, the measuring module 114 can also perform the measurement of at least one electrical parameter selected from the group consisting of:

[0109] f: frequency

[0110] current-to-voltage phase shift

[0111] power factor, I F / v FN

[0112] power factor, I N / v FN

[0113] T: temperature

[0114] Additionally, as an example, the first measuring device 115 and the second measuring device 116 are configured to calculate at least one additional parameter selected from the group consisting of: active power p, reactive power q, active quantity, and reactive quantity. Specifically, the corresponding waveforms and RMS values ​​are calculated for the electrical parameters listed above.

[0115] The control and measurement device 101 can also perform calculations of other parameters, such as differential current and / or ground loop impedance, by means of the control and processing device 113.

[0116] As an example, the control and processing device 113 determines the power factor based on the following equation. and power factor Considering the measured parameter phase current I under power factor correction F and neutral current I N To calculate the differential current:

[0117]

[0118] According to the example, the ground loop impedance Re is used by the control and measurement device 101 (independent of the variable load device 102) as a reference to the neutral point voltage V. FN and relative ground voltage V FT Difference between the two divided by the differential current I Δn To evaluate:

[0119]

[0120] It has been observed that the ground loop impedance Re can also be evaluated through the cooperation of control and measurement device 101 and variable load device 102. For example... Figure 6 As shown, when the first switch 143 is open, the voltage V0 between the phase conductor PC and the ground conductor GC is measured by the first voltmeter 118. When the first switch 143 is closed, a first variable impedance 142 with negligible resistance R0 is introduced by the variable load device 102 between the phase conductor PC and the ground conductor GC: the corresponding voltage V1 is measured by the first voltmeter 118, and the phase current I is measured by the first ammeter 117. F The grounding loop impedance Re can be obtained from the following equation:

[0121]

[0122] According to a particular embodiment, the control and measurement device 101 is also configured to detect specific events occurring in the electrical installation 103. In particular, at least one of the following detections can be performed: AC detection, overcurrent detection, overvoltage detection, undervoltage detection, and abnormal frequency detection.

[0123] The AC detection is triggered when the phase-to-neutral voltage is zero. The overcurrent detection is triggered when the phase current reaches a threshold current value. The overvoltage detection is triggered when the phase-to-neutral voltage reaches a maximum threshold voltage value. The undervoltage detection is triggered when the phase-to-neutral voltage reaches a minimum threshold voltage value.

[0124] The control and measurement device 101 can also be configured to automatically perform the monitoring (both historical and real-time) of the main parameters of the electrical installation 103, such as: load and ground voltage (to verify the nominal values), load and differential current (to verify potential faults), active and reactive power, ground connection.

[0125] It is noted that, as an example, the control and measurement device 101 can be configured to send, via the server computer device 200, a notification of a specific detected event to the user device 301. According to an embodiment, the user can be notified in the following cases: the system behaves abnormally (unsafe connected device, ground loop connection fault, electrical input parameters mismatch or temperature too high in the electrical cabinet, etc.); there is no power supply; signal loss; system maintenance is required.

[0126] It is also observed that, even if the above description refers to a single-phase electrical installation 103, the electrical installation measurement system 100 can be used to measure electrical parameters in a three-phase electrical installation. The skilled person recognizes that, for the other two-phase conductors of a three-phase electrical installation, the exemplary measurements described with reference to the single-phase conductor PC can also be performed. In this case, the number of measurement devices included in the control and measurement device 101, similar to the first measurement device 115, can be selected so as to allow the measurement of electrical parameters related to the other two phase conductors of the three-phase electrical installation.

[0127] The described electrical installation measurement system 100 provides advantages for the professional technician. In particular, the electrical installation measurement system 100 allows to perform the required measurements and tests in an easier and faster way compared to what is obtainable with traditional devices. The electrical installation measurement system 100 can be manufactured with non-expensive components.

[0128] Moreover, the described electrical installation measurement system 100 can also provide advantages for the end user (i.e. the home owner). In particular, the automatic monitoring of the electrical installation can actively increase its safety, provide information about potential fault conditions, and control the electricity consumption.

Claims

1. An electrical installation measurement system (100) comprising: - a control and measurement device (101) designed to be installed and electrically connected to a distribution board (104) of an electrical installation (103) and configured to: perform at least one measurement of an electrical parameter of the electrical installation (103) in function of an electrical load connected to the electrical installation (103), including at least one of the following measurements: estimation of a differential switch tripping current; estimation of a differential switch tripping time; and send a command signal (SCM) along a telecommunication link; - a variable load device (102) connectable to the electrical installation (103) and configured to: receive the command signal (SCM) from the telecommunication link; and adopt a plurality of load configurations according to the command signal (SCM); wherein the variable load device (102) is portable and comprises: an electrical plug (139) to be connected to a socket (112) of the electrical installation (103), the electrical plug comprising a first terminal (144), a second terminal (145) and a third terminal (146); a variable impedance module (136) comprising: a first adjustable impedance device (140) comprising at least one first variable impedance (142) and a first switch (143); the at least one first variable impedance (142) having a first impedance terminal connected to the second terminal (145) and a second impedance terminal connected to the first switch (143) connected to the first terminal (144) of the plug (139); the first switch (143) being configured to be closed / opened to connect / disconnect the first variable impedance (142) to / from the first terminal (144); a second adjustable impedance device (141) comprising at least one second variable impedance (147) and a second switch (148); the second variable impedance (147) comprising a third impedance terminal connected to the third terminal (146) of the plug (139) and a fourth impedance terminal connected to the second switch (148) connected to the first terminal (144) of the plug (139); the second switch (148) being configured to be closed / opened to connect / disconnect the second variable impedance (147) to / from the first terminal (144).

2. The measurement system (100) of claim 1, wherein: the first adjustable impedance device (140) and the second adjustable impedance device (141) are configured to adopt a plurality of impedance values according to the plurality of load configurations; and the variable load device (102) comprises a control device (135) configured to generate a control signal (SA) to select the plurality of impedance values according to the command signal (SCM).

3. The measurement system (100) of claim 1 or 2, wherein the control and measurement device (101) comprises: a measurement module (114) configured to perform the at least one measurement of the electrical parameter of the electrical installation (103); ​ ​ ​ ​ a first wireless communication module (127) configured to transmit said command signal (SCM); a control and processing device (113) configured to manage the operation of the measuring module (114) and of the first wireless communication module (127).

4. The measuring system (100) of claim 3, wherein the variable load device (102) comprises: a second wireless communication module (137) configured to receive said command signal (SCM) from the first wireless communication module (127); and wherein the control device (135) is connected to said second wireless communication module (137) and is configured to manage the operation of the variable impedance module (136) as a function of the command signal (SCM).

5. The measuring system (100) of claim 4, wherein each of said first variable impedance (142) and of said second variable impedance (147) comprises at least one electrical device selected from the group consisting of: a variable resistance load, a variable inductance load, a variable capacitance load.

6. The measuring system (100) of claim 1, wherein said control and measuring device (101) is configured to perform a measuring procedure by: - transmitting a procedure command signal (SCM) to cause the variable load device (102) to assume a procedure load configuration when connected to the electrical installation (103); - performing said at least one measurement of an electrical parameter of the electrical installation (103) as a function of said procedure load configuration assumed by the variable load device (102) to provide at least one measured value.

7. The measuring system (100) of claim 6, wherein said control and measuring device (101) is further configured to process said at least one measured value to produce at least one computed electrical parameter.

8. The measuring system (100) of claim 1, wherein the control and measuring device (101) comprises: a first voltmeter (118) to be connected between a phase conductor (PC) and a ground conductor (GC) of the electrical installation (103); a second voltmeter (120) to be connected between the phase conductor (PC) and a neutral conductor (NC) of the electrical installation (103); a first ammeter (117) to be connected to the phase conductor (PC); a second ammeter (119) to be connected to the neutral conductor (NC).

9. The measuring system (100) of claim 6, wherein said system is configured to perform, as a function of said measuring procedure, at least one measurement selected from the group consisting of: measurement of the ground return impedance; measurement of the voltage drop over a portion of the electrical installation (103); estimation of the short-circuit current; test of the behavior of a magnetic thermal switch.

10. The measuring system (100) of claim 1 or 2, wherein said system further comprises: at least one computer device (200) external to the control and measuring device (101) and configured to exchange data with said control and measuring device (101) and to store values of electrical parameters; 11. The measuring system (100) of claim 10, wherein said computer device (200) is configured to perform a procedure of: - receiving at least one measured value from the control and measuring device (101); - processing said at least one measured value to produce at least one computed electrical parameter; - storing said at least one computed electrical parameter. at least one client device (300, 301) configured to exchange data / information with said control and measurement device (101) and to access stored values by a user of said at least one client device.

11. The measurement system (100) of claim 4, wherein each of the control and measurement device (101) and the variable load device (102) comprises: a respective housing (134, 153) and a respective power supply module (125; 138)。 12. The measurement system (100) according to claim 1 or 2, wherein said system is configured to operate on electrical installations (103) selected from the following types: single-phase electrical installations, three-phase electrical installations.

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