WO1999042846A1 - Method for measuring and controlling electrical parameters in a low voltage industrial alternating current electric installation and equipment for implementing said method - Google Patents

Abstract

The invention concerns a method and equipment for centralising both voltage and intensity level sensing and processing of said parameters to facilitate measurement and control of all the electrical parameters of an installation, reduce costs, while improving efficiency and security of personnel and equipment. The equipment (2) is characterised in that it comprises: a single sensing module (3) connected to the electric installation (1) conductors (P1, P2, P3, N) and arranged to pick up analog signals corresponding at least to said installation voltage (U1, U2, U3, Un) and intensity (I1, I2, I3) levels; a central processing unit (4) connected to the sensing module (3) for receiving said signals, said unit comprising at least means for converting analog signals into digital signals corresponding to the values of said electrical parameters; a communication bus (5) connected to the processing unit (4) for transmitting said digital signals; and at least a link-attached apparatus for reading and operating on (6) said signals and arranged for transforming them into values corresponding to said electrical parameters capable of being displayed. The invention is applicable to industrial electric installations.

Description

PROCESS FOR MEASURING AND CONTROLLING THE ELECTRICAL PARAMETERS OF A LOW-VOLTAGE INDUSTRIAL ELECTRICAL SYSTEM IN ALTERNATE SYSTEM AND EQUIPMENT FOR IMPLEMENTING SAID METHOD

The present invention relates to a method for measuring and controlling the electrical parameters of a low-voltage industrial electrical installation in alternating mode, for example a three-phase installation with or without neutral, as well as equipment for implementing said method.

In general, in industrial electrical installations at low voltage and in alternating regime, there is a need to measure, control, manage, monitor, count some or all of the electrical parameters of the network, namely: the voltages between phases or between phase and neutral, the currents on each phase, the active power, the reactive power, the apparent power, the instantaneous peak power, the instantaneous peak energy calculated over 10 or 15 minutes for example and the cumulative electric energy, the power factor or cosine phi, frequency, etc.

To carry out these measurements and checks, there is a multitude of reading and operating devices specific for each parameter or common to several parameters, such as indicators (voltage, current, frequency, power, etc.), transducers, current or voltage relays, energy management devices, meters and any other measurement and control device. Each device must be connected to the electrical installation to capture voltages, currents and possibly other electrical parameters and must be supplied with electricity to operate. This connection requires the user to mount a current transformer on each phase, a voltage tap protected by a fuse or a circuit breaker on each phase and on the neutral and to wire an electrical supply. It is easy to understand that these different connections and cabling are tedious, that they require long interventions as well as specific material. In addition, in industry, the control and management of electrical parameters are generally centralized in a control room remote from the installation. In this case, it is necessary to provide connecting cable lengths accordingly.

In addition, each reading and operating device is equipped as standard with at least one input stage receiving the signals corresponding to the captured parameters such as voltages and currents, a processing stage which conditions and converts these signals in values, and as the case may be, determines the values of other electrical parameters of the installation by calculation or integration, and a display stage for these values. Therefore, these devices are relatively expensive and the range of devices available from manufacturers is important to meet the needs of all customers.

A priori, there is no solution to rationalize these measures and controls. The only devices used to centralize certain electrical parameters and then process them are used in the metering of household energy. In this case, the different consumer lines are connected to a central processing unit and the only parameter taken into account is the electrical energy consumed.

In other fields of application, devices arranged to centralize certain functions are used, such as for example in the publication US-A-5,428,553 which describes a protection relay intended for the protection of medium and high voltage networks. , which is used in an industrial backplane bus (VME) rack.

This protection relay comprises, in the same housing and at the same location, input functions of voltages U and intensities I, a central unit, an I / O module, a display and adjustment means. The essential aim of this invention is to distribute the different functions (inputs, display, outputs) on different cards each comprising a digital signal processor in order to carry out processing in parallel and gain either in processing speed or in precision for the network protection function. It is important to note that this solution is very expensive because a VME bus is certainly very fast but limited in distance since it must be in the same rack, which is also very expensive. This particularly expensive system was chosen specifically for its extreme reliability which is necessary for medium and high voltage networks where any loss of equipment by default (accident) is excluded.

Another device is described in international publication WO-A-94/03818 concerning an electrical network analyzer which performs in a single housing the measurement of electrical parameters: voltages U, intensities L, frequency and cosine phi then transmits them to a card Internal PC via an internal bus which can transmit them to a networked computer. There is no mention of remote reading and operating devices, separated from the central unit and connected via a serial bus. It is also not specified that the signals are captured by a single sensor module.

The object of the present invention is to solve the drawbacks mentioned above by proposing a method and equipment making it possible to facilitate the implementation of the measurements and the controls to be carried out on industrial low-voltage electrical installations. They essentially consist in centralizing both the capture of voltages and currents, and, the processing and conversion of the signals picked up into signals which can be used directly by remote reading and operating devices, then in transmitting these usable signals to said reading devices. deported and located at any distance from the catchment area. Thus, the assembly of the current transformers and the voltage taps is carried out in a single operation whatever the number of reading and operating devices provided for collecting, managing and displaying the various electrical parameters of an installation. In addition, the invention makes it possible to add other remote reading and operating devices, or any other electrical apparatus, easily. and quickly without the need to wire a specific power supply and connect it electrically to the installation.

To this end, the method according to the invention as defined in the preamble is characterized in that:

- the analog signals corresponding to the electrical parameters of the installation are picked up by means of a single sensor module connected to the conductors of the electrical installation,

these analog signals are transmitted to a central processing unit, these analog signals are processed and converted into digital signals corresponding to values of said electrical parameters by means of said central processing unit,

- these digital signals are transmitted by means of a communication bus to at least one remote reading and operating device, - these digital signals are recovered by means of at least said remote reading and operating device ,

- The values of said electrical parameters are processed and displayed on at least said reading and operating device as a function of the digital signals received.

Preferably, said central processing unit is electrically supplied by the sensor module and it is possible to supply said reading and operating device by means of a supply bus provided at the output of said central processing unit. treatment.

The invention also relates to the device implementing the method mentioned above, characterized in that it comprises:

- a single sensor module connected to the conductors of the electrical installation and arranged to pick up the analog signals corresponding at least to the voltages and intensities of this installation, a central processing unit connected to the sensor module for receiving said signals, this central unit comprising at least means for converting these analog signals into digital signals corresponding to the values of said electrical parameters, and performing calculations on these values to determine other values ,

a communication bus connected to the central processing unit for transmitting said digital signals to at least one remote reading and operating device, and

- At least said device for reading and processing these digital signals arranged to transform them into displayable values corresponding to said electrical parameters.

In a first embodiment, the sensor module and the central processing unit are each housed in an independent box and are connected by an electric cable.

In a second variant embodiment, the sensor module and the central processing unit are integrated in the same housing.

In a preferred form of the invention, the central processing unit comprises at least:

- a multiplexer which receives the analog signals corresponding to the voltages and intensities picked up by the sensor module and transmits them to an amplification stage with variable gain,

a microcontroller which alternately selects said analog signals in the multiplexer and chooses the gain of the amplification stage as a function of said signals,

- an analog / digital conversion stage which converts analog signals into digital signals, a processing module which comprises the microcontroller, calculates certain values of the electrical parameters of said installation by calculation and transmits them in the form of digital signals to a communication interface, and

- a communication interface which receives the digital signals from the processing module and formats them according to a defined communication protocol.

In this preferred form, the reading and operating device comprises at least:

- a communication interface which receives the digital signals transmitted by the communication bus, - a processing stage of the communication protocol which decodes the signals,

a processing unit which comprises at least one microcontroller arranged to format said decoded signals as a function of the value of the electrical parameter to be displayed, and

- a digital display to display the value of said electrical parameter measured or calculated.

The reading and operating device can be selected from the group comprising at least a multi-measurement device, an energy management device, an energy meter, a display device, a transducer, a detection relay. thresholds, a remote input and output module.

The transducer preferably comprises, in place of the display, a digital / analog conversion stage, internal or external to the microcontroller of the processing unit, which transforms the digital signals into analog signals of very low values usable by other electrical appliances.

The equipment can comprise a communication gateway arranged to connect said communication bus to another communication bus having a different protocol, this communication gateway comprising at least: - an input communication interface which receives the digital signals transmitted by the communication bus of said equipment,

- a communication protocol processing stage which decodes the signals,

a processing module which comprises at least one microcontroller arranged to format the decoded signals,

a processing stage of a different communication protocol which recodifies these signals, and

- an output communication interface which transmits said recoded digital signals to the other communication bus.

The central processing unit can advantageously be supplied electrically by means of the sensor module and can comprise an electric supply bus arranged to supply electrically the reading and operating devices.

The present invention and its advantages will appear more clearly in the following description of an exemplary embodiment, with reference to the appended drawings, in which:

FIG. 1 represents a diagram of an electrical installation and of the measurement and control device according to the invention,

FIG. 2 is a block diagram of the central processing unit of the device of FIG. 1,

FIG. 3 is a block diagram of an apparatus for exploiting the electrical parameters of the installation of the display type,

FIG. 4 is a block diagram of a transducer, and

Figure 5 is a block diagram of an additional communication module. With reference to FIG. 1, an industrial electrical installation 1 low voltage in alternating mode comprises for example four electrical conductors, corresponding to the three phase conductors PI, P2, P3 and to the neutral conductor N, the latter being not always necessary. . The equipment 2 for measuring and controlling the electrical parameters of this installation includes:

- a single sensor module 3 connected to the conductors of the electrical installation and arranged to receive the analog signals corresponding to the electrical parameters of this installation,

a central processing unit 4 connected to the sensor module 3 for receiving said signals, this unit comprising at least means for converting these analog signals into digital signals corresponding to the values of said electrical parameters,

- A communication bus 5 connected to the central processing unit for transmitting said digital signals, and - at least one reading and processing device 6 for these remote signals arranged to transform them into displayable and usable values corresponding to said electrical parameters.

The sensor module 2 comprises four internal conductors corresponding to the conductors of the installation 1, a current transformer mounted on each phase conductor PI, P2, P3 and a voltage tap connected to each phase conductor PI, P2, P3 and of neutral N. These voltage taps can for example be integrated into the current transformers by perforation of the insulation surrounding said conductors. The intensity transformers are coupled to a calibration device which makes it possible to cover a wide range of intensities, for example from 5 to 160A without having to change them. Analog signals corresponding to the voltages between phases and neutral Ul, U2, U3, Un and to the intensities on each phase

II, 12, 13 are collected in a conventional output connector. This single sensor module 3 will not be described in more detail since it is the subject of a French patent application published under the number 2,745,910 of the same holder. In the case where the intensities II, 12, 13 of the industrial electrical installation are greater than 200 amperes, the conductors PI, P2, P3 are busbars and then use current transformers of higher capacity which are generally external to the sensor module 3 and mounted directly on these bars.

The central processing unit 4 comprises, with reference to FIG. 2:

- an input connector 7 connected to the output connector of the sensor module 3 by an electric cable 8, - a multiplexer 9 which receives the analog input signals corresponding to the voltages Ul, U2, U3, Un and to the intensities II, 12 , 13 picked up by the sensor module 3 and transmits them to an amplification stage 10 with variable gain,

- an analog / digital conversion stage 11 which converts the amplified analog signals into digital signals, - a processing module 12 which on the one hand controls the multiplexer and the amplification stage and on the other hand determines by calculation certain values electrical parameters of said installation as a function of the voltages and intensities sensed to transmit them in the form of digital signals to a communication interface 13, and - a communication interface 13 which receives the digital signals from the processing module 12 and puts them shaped according to a defined communication protocol, for example CAN (Control Area Network), for transmitting them on the communication bus 5, for example by serial link of the RS485 type, and allowing the reading and operating devices 6 which are connected on this bus to retrieve these digital signals to read and use them.

The processing module 12 comprises a microcontroller which alternately selects all of the analog input signals Ul, U2, U3, Un, II, 12, 13 in the multiplexer 9 by a link A, to scan their value and transmit them to the amplification stage 10. The cycle for examining all the input signals is for example 10

about 600 μs. Furthermore, the microcontroller controls and adjusts the value of the amplification gain as a function of the analog signal selected in the multiplexer 9 by a link B. This makes it possible to simplify the amplification stage 10 by having only a single stage amplification instead of an amplification stage by type of signal to be processed. This microcontroller also calculates, from the analog input signals, the values of the following electrical parameters:

• the effective instantaneous intensity (on the three phases and the neutral)

• the effective instantaneous voltage (on the three phases and the neutral)

• three-phase instantaneous active power • three-phase instantaneous reactive power

• the three-phase instantaneous apparent power

• frequency

• the power factor (s) or the phi cosine (s)

• the instantaneous peak powers • the instantaneous peak intensity

• instantaneous energy and / or peak energy calculated for example over the last 10 or 15 minutes.

After the calculation of these values by any existing method, for example integration by the trapezoid method, the processing module 12 transmits them in the form of a 16-bit digital signal and cyclically to the communication interface

13.

For an electrical installation where the intensity is less than 200 amperes, the central processing unit 4 and the sensor module 3 can advantageously be integrated in a single housing. In this case, the economy achieved compared to the state of the art is very significant given the much simpler and faster implementation of the equipment 2. In addition, the installation 1 can easily evolve taking into account of the wide range of intensities covered by the sensor module 2. Beyond an intensity of 200 amperes, the central processing unit 4 is necessarily separated from the sensor module 3 taking into account the specific intensity transformers that are necessary 11

plan, but it is at most a few meters away from the phase conductors P1JP2 and P3.

As an option, this processing unit 4 can be equipped with a supply bus 14 intended to supply the various reading and operating devices electrically.

6. This power supply includes a transformer 15 whose input, for example at 380V, is connected to two voltage inlets before the multiplexer 9 and the output, for example at 12V, is connected to a voltage regulator 16 which supplies the supply bus 14 intended to supply the various reading and operating devices 6.

The reading and operating devices 6 are located at a distance from the sensor module 2, this distance being not limited. They are said to be deported. They are connected to the sensor module 2 by the communication 5 and power bus 14. These devices can be of different types, such as for example: a multi-measurement device 61, an energy management device 62, an energy meter 63, a digital indicator 64.

These reading and operating devices 61 to 64 have substantially the same configuration and comprise at least, with reference to FIG. 3: - an input connector 19 intended to be connected to the communication bus 5,

a communication interface 20 which receives the digital signals transmitted by the communication bus 5,

a processing stage 21 of the communication protocol which decodes the signals,

a processing unit 22 which comprises at least one microcontroller arranged to format said decoded signals as a function of the value of the electrical parameter to be displayed, and

- a digital display 23 for displaying the value of said electrical parameter measured or calculated. 12

In the case of a multi-measurement device 61, there is added a selection button 24 on the front of the device for selecting the electrical parameter to be displayed. D. is thus possible to selectively display currents, voltages, frequency, etc. i.e. all the electrical parameters of the installation.

The energy management appliance 62 is interested, in addition to the functions of the preceding appliance 61, in powers, instantaneous energy, tariff management (for example off-peak / peak hours, EJP tariff, etc.), power peaks with penalties, etc.

The energy counter 63 only displays the value corresponding to the energy consumed transmitted by the central processing unit 4. It does not make any calculation. Similarly, the digital indicators 64 only display the values transmitted by the central processing unit 4 without carrying out any calculation. For example, an ammeter is designed to receive only digital signals corresponding to the three-phase current parameters (II, 12, 13). D. the same applies to the voltage, power, frequency, etc. indicators. A selection button on the front panel makes it possible to display the value of said parameter of each phase PI, P2, P3.

The reading and operating device can also be a transducer 65. In this case and with reference to FIG. 4, we find the same configuration as before but the digital display 23 is replaced by:

a digital / analog conversion stage or principle 25 which transforms the digital signals into analog signals corresponding to very low voltage or intensity values, for example a voltage of 0 to 10 V, an intensity of 4 to

20 m_A or from 0 to 20 mA, usable in industry by other electrical devices such as for example automats, electronic cards;

- A communication interface 26 which receives these analog signals and puts them in a defined configuration to send them to an output connector 27 intended to supply said other electrical devices by a usual electrical cable. It is also possible to connect other electrical devices, such as a threshold relay 66, a remote input and output module 67, a permanent insulation controller 70, a differential toroid 71 or a differential relay, a temperature probe 72 for example of the PT100 type.

The threshold relay 66 is directly connected to the communication bus 5 and makes it possible to detect the digital signals transmitted by the central processing unit 4 and corresponding to the values of electrical parameters exceeding a threshold configured in the device 66. The characteristics operating modes of threshold relay 66 can be configured, namely threshold values, hysteresis, time delay. If this threshold is exceeded, this threshold relay 66 can control, for example, a cut-off device, a generator, a load shedding circuit.

The input and output module 67 is also directly connected to the communication bus 5. It can, for example, be a digital input which receives electrical signals from auxiliary contacts coupled to switches arranged on said electrical installation 1 but downstream of said equipment 2. These auxiliary contacts generally provide information relating to the open or closed state of these switches. The output can for example control a motor for actuating a switch according to the state of the network.

In a variant shown in dotted lines in FIG. 2, the processing unit 4 can directly include an optional remote input / output module 67 ′ whose functions are identical to module 67, as well as an optional communication gateway 69 ′ identical to that of reference 69 described below.

The permanent insulation controller 70 is connected to the neutral conductor N of the installation 1 and makes it possible to detect any leaks due to an insulation fault. 14

This controller 70 is connected to the communication bus 5 by an appropriate interface 73 to forward this information to the central processing unit 4 or send it directly to other electrical devices connected to this bus.

The differential toroid 71 is arranged around the conductors PI, P2, P3 and N of the installation 1 and makes it possible to detect any leaks to the ground. This differential toroid 71 is connected to the communication bus 5 by a differential relay 74 and an appropriate interface 75 for forwarding this information to the central processing unit 4 or sending it directly to other electrical devices connected to this bus. In some cases, a single specific interface 75 may be sufficient to connect the differential toroid 71 to the communication bus 5.

The temperature probe 72 for example of the PT100 type is for example placed in the electrical control cabinet or on the busbar of said installation 1 and makes it possible to provide information relating to the operating temperature. It is also connected to the communication bus 5 by an appropriate interface 76 to forward this information to the central processing unit 4 or send it directly to other electrical devices connected to this bus.

The equipment 2 as defined above can be connected to a computer 68 equipped with supervision software which makes it possible to retrieve the values of the various electrical parameters to use them but also to program adjustment parameters on the various devices 6 connected. This computer 68 can generally supervise several industrial electrical installations and is located for example in a control room of a factory. In the case where this computer 68 is already connected to an existing communication bus 28 which transmits the electrical parameters of one or more other installations but which operates on the basis of another protocol, a communication gateway 69 is inserted between this existing communication bus 28 and the communication bus 5 of said equipment 2. This communication gateway 69 has a configuration similar to that already described in with reference to FIG. 3 but instead of the digital display 23 and with reference to FIG. 5:

- A processing stage 29 of a different communication protocol which recodes these signals, and - an output communication interface 30 which transmits said recoded digital signals to the existing communication bus 28 by an output connector 31. This communication gateway 69 allows for example to connect a communication bus 5, the Uaison of which is of the RS485 type with the CAN protocol, to a communication bus 28, the House of which is of the RS232 or Ethernet type with the protocol

Jbus or TCP-IP, any other configuration being possible.

In the same context, another piece of equipment 2 ′ corresponding to another industrial electrical installation 1c can be connected to the same communication bus 5 if the type of use and the communication protocols are the same. In this case, the reading and operating devices 6 can be the same, a selection button making it possible to choose the number of the installation 1 or the one to be controlled being provided on these devices, which makes it possible to use the values of network 1 or l 'on equipment 2 or 2' of your choice. This system is not limited to two networks but can be extended to 1 "networks, etc., and to 2" equipment, etc., without limitation.

It is also important to note that this equipment 2 considerably improves safety for people and the electrical equipment used. Indeed, in the state of the art, the reading and operating devices are supplied directly by the installation, that is to say that the measured voltage is equal to the voltage supplying these devices, for example 380 V. In this equipment 2, the devices 6 can be supplied directly with very low voltage, for example 12 V thanks to the supply bus 14 provided at the output of the central processing unit 4 and the voltage levels of the communication bus are less than 5 V. In addition, thanks to this equipment 2, U is no longer possible to make a mounting or wiring or inversion error in the mounting of the current transformers (in the case where the current transformers are integrated into the sensor module 3). Only operations to configure the various modules, units and devices remain to be performed. As a result, this equipment enables significant savings to be made in the implementation and control operations which are no longer necessary.

Another advantage lies in the fact that the sensor module 3 and the central processing unit 4 are located close to the conductors of the installation 1 and at most 1 meter for example. Then, the communication bus 5 can supply the various devices to any location in the factory without any difficulty or difficulty in terms of the quality and response time of the information transmitted. This advantage allows a significant gain in wiring compared to the state of the art.

The assembly of this equipment 2 is therefore simplified to the maximum. The operator must do the following:

- connect the sensor module 3 to the conductors of installation 1, either by simply connecting its inputs if the current is less than 200 A, or by mounting the current transformers directly on the busbars if the current is higher at 200 A,

- connect the central processing unit 4 to the sensor module 3 if it is not already integrated in said module,

- connect the communication bus 5 and possibly the power bus 14,

- connect the various remote reading and operating devices 6 and others to buses 5, 14,

- configure the various devices according to the parameters to be measured.

If an electrical appliance is later to be connected to this equipment, it suffices to connect it directly to the communication bus 5 and possibly to the supply bus 14. The above description shows that the invention achieves all the aims mentioned.

Of course, the present invention is not limited to the example of réaUsation described but extends to any modification and variant obvious to a person skilled in the art.

Claims

claims 1. Method for measuring and controlling the electrical parameters of a low-voltage alternating mode industrial electrical installation, for example a three-phase installation with or without neutral, characterized in that: - the analog signals corresponding to the electrical parameters of the installation are picked up by means of a single sensor module connected to the conductors of the electrical installation, these analog signals are transmitted to a central processing unit, these analog signals are processed and converted into digital signals corresponding to values of said electrical parameters by means of said central processing unit, - these digital signals are transmitted by means of a communication bus to at least one remote reading and operating device, - these digital signals are recovered by means of at least said remote reading and operating device , - The values of said electrical parameters are processed and displayed on at least said remote reading and operating device as a function of the digital signals received. 2. Method according to claim 1, characterized in that the said central processing unit is supplied electrically by means of the sensor module. 3. Method according to claim 2, characterized in that said remote reading and operating device is supplied by means of a supply bus provided at the output of the central processing unit. 4. Equipment (2) for implementing the method according to any one of the preceding claims, characterized in that U comprises: - a single sensor module (3) connected to the conductors (PI, P2, P3, N) of the electrical installation (1) and arranged to pick up the analog signals corresponding at least to the voltages (Ul, U2, U3, Un) and at the intensities (II, 12, 13) of this installation, - a central processing unit (4) received from the sensor module (3) to receive said signals, this central unit comprising at least means for converting these analog signals into corresponding digital signals to the values of said electrical parameters, and perform calculations on these values to determine other values, - a communication bus (5) connected to the central processing unit (4) for transmitting said digital signals to at least one device of remote reading and operating, and - At least said remote reading and operating device (6) arranged to transform said digital signals into displayable values corresponding to said electrical parameters. 5. Equipment according to claim 4, characterized in that the sensor module (3) and the central processing unit (4) are each housed in an independent housing and are reUés by an electric cable. 6. Equipment according to claim 4, characterized in that the sensor module (3) and the central processing unit (4) are integrated in the same housing. 7. Equipment according to claim 4, characterized in that the central processing unit (4) comprises at least: - a multiplexer (9) which receives the analog signals corresponding to the voltages and intensities picked up by the sensor module (3) and transmits them to an amplification stage (10) with variable gain, a microcontroller which alternately selects said analog signals in the multiplexer (9) and chooses the gain of the amplification stage (10) as a function of said signals, - an analog / digital conversion stage (11) which converts the analog signals into digital signals, - a processing module (12) which comprises the microcontroller, determines by calculation certain values of the electrical parameters of said installation and transmits them in the form of digital signals to a communication interface, and - a communication interface (13) which receives digital signals from the processing module and formats them according to a defined communication protocol. 8. Equipment according to claim 7, characterized in that the reading and operating apparatus (6) comprises at least: - a communication interface (20) which receives the digital signals transmitted by the communication bus (5) , - a processing stage (21) of the communication protocol which decodes the signals, a processing unit (22) which comprises at least one microcontroller arranged to format said decoded signals as a function of the value of the electrical parameter to be displayed, and - a digital display (23) to display the value of said electrical parameter measured or calculated. 9. Equipment according to claim 8, characterized in that the reading and operating device (6) is selected from the group comprising a multi-measurement device (61), an energy management device (62), a counter. energy (63), a display device (64), a transducer (65), a threshold detection relay (66), a remote input and output module (67). 10. Equipment according to claim 9, characterized in that the transducer (65) comprises, in place of the display (23), a digital / analog conversion stage (25), internal or external to the microcontroller of the unit processing, which transforms digital signals into analog signals of very low values usable by other electrical devices. 11. Equipment according to claim 4, characterized in that U comprises a communication passereUe (69) arranged to receive said communication bus (5) to another communication bus (28) having a different protocol, this communication passereUe comprising at least: - an input communication interface (20) which receives the digital signals transmitted by the communication bus of said equipment, a processing stage (21) of the communication protocol which decodes the signals, a processing module (22) which comprises at least one microcontroller arranged to format the decoded signals, - a processing stage (29) of a different communication protocol which recodifies these signals, and - an output communication interface (30) which transmits said recoded digital signals to the other communication bus. 12. Equipment according to claim 4, characterized in that the central processing unit (4) is electrically supplied via the sensor module (3). 13. Equipment according to claim 12, characterized in that the central processing unit (4) comprises an electrical supply bus (14) arranged to electrically supply the reading and operating devices (6).