EP0501887A1 - Device and process of monitoring at least one light source - Google Patents

Abstract

The process comprises a step consisting in detecting normal operation of the light source and in emitting a normal operation signal and, in the event of a fault or abnormal operation, in emitting a signal which differs from the normal operation signal. The device for implementing the process comprises an individual item of equipment (2) associated with a light source (1) for emitting a signal of normal operation of the said source and a signal which differs from the said signal in the event of abnormal operation or a fault, protected by at least one protection device (6) associated with a light source (1). The individual items of equipment (2) are connected up via a supply line (3) to a central item of equipment (4) situated in a supply cabinet (5). The central item of equipment (4) converses with a central cut-in station (6) through telecommunication means (7). Application to the monitoring of public lighting networks. <IMAGE>

Description

The invention relates to a method for monitoring at least one source of light radiation as well as a device for implementing said method.

The invention relates more particularly to the monitoring of a plurality of public lighting sources. The monitoring of a public lighting network can be carried out by personnel when the network is energized by observing the operation of the sources. This results in significant personnel costs.

Several solutions have been proposed to overcome these drawbacks.

There is known, according to French patent FR-A-2,592,718, a monitoring method according to which the radiation emitted by a live source is detected, and a single frequency failure signal is emitted, for example at a musical frequency. Each source is associated with an individual item of equipment emitting the above-mentioned monofrequency signal.

As this single frequency signal is only emitted in the event of a failure, it is not possible, in the absence of a signal, to determine what is the nature of the failure: failure of the individual equipment or of the radiation source.

According to French patent application 88.08017, a monitoring method and system are known which use a low voltage at the industrial frequency to monitor light sources. This system can only be used when the source is switched off, preferably shortly after switching off. This system does not make it possible to date and memorize the events or to identify the nature of the failure.

The object of the invention is to remedy the aforementioned drawbacks by creating an improved method and device for monitoring light sources.

The method according to the invention for monitoring at least one source of light radiation connected to a supply network is characterized in that it comprises at least one step consisting, using individual equipment associated with the radiation source, detecting the normal operation of the radiation source and emitting a normal operating signal, and, in the event of a fault or abnormal operation, emitting a signal different from said signal normal operation, said different signal possibly consisting of an absence of signal.

Thus, during normal operation of the radiation source, a signal is regularly emitted. If this signal is a normal operating signal, no event is recorded. If this signal is a signal different from the normal operating signal, the fault is identified and stored. This thus makes it possible to establish the list of failures and to prepare intervention plans.

The signals relating to a given radiation source are advantageously transmitted over a supply line to said radiation source and received, at a point on said line remote from said source, by central equipment.

Thus, a single central equipment is used to date and memorize failures relating to various sources of radiation with which it communicates. A substantial saving is thus achieved by allocating the dating and storage means of a single central item of equipment to several sources of radiation.

Preferably, a signal corresponding to a given radiation source is emitted regularly by the associated individual equipment during a predetermined time interval.

Thus, since the signals are transmitted over the supply lines of the radiation sources and each signal is transmitted in turn during a predetermined time interval, all the signals are transmitted over the supply lines of the sources without using any additional transmission line.

Preferably also, when it is desired to monitor an ordered plurality of sources, the normal operating or failure signal is emitted after the expiration of a predetermined time interval and then of a time interval depending on a number d order of the radiation source within said plurality of sources.

A source of radiation given by its position within a time sequence is thus identified and the state of said source is identified by the associated signal.

In an advantageous embodiment of the invention, the signal different from the normal operating signal indicates the nature of the failure of the radiation source.

Thus, depending on the nature of the failure, the necessary repair means are brought in, avoiding, when it is not necessary, the costly displacement of a ladder car.

According to a preferred embodiment of the invention, the signals transmitted by individual equipment are signals of musical frequencies.

These signals relating to a given radiation source are, in the event of failure or abnormal operation, identified, memorized and transmitted to a central intervention station, preferably by telephone line. Thus, a central intervention station is sufficient to monitor, maintain and repair a large public lighting installation, depending for example on an urban community.

The invention also relates to a device for implementing the above method.

A device according to the invention is characterized in that it comprises individual equipment associated with a radiation source, for emitting a normal operating signal from said source and a signal different from said normal operating signal, in the event of abnormal operation or failure of said source.

This device comprises central equipment connected to at least one individual equipment by a supply line from said source.

In the case of monitoring an ordered plurality of sources, the device comprises scanning means for interrogating individual items of equipment and causing them to be transmitted according to an ordered cycle in the direction of the central equipment to which they are connected. Each individual device transmits during a predetermined time interval and the time interval is determined so as not to overlap the emissions of two separate individual devices. Preferably said scanning means comprise at least one microprocessor.

Preferably also, the individual equipment is able to emit a different signal depending on the nature of the abnormal operation or the failure of the light radiation source.

A device according to the invention advantageously comprises means of dating, storage and transmission by means of telecommunication by telephone line or the like, to a central intervention station.

Individual equipment of a device according to the invention is advantageously protected by at least one protection device associated with a radiation source which simultaneously protects said individual equipment and said radiation source.

• Les figures 1A et 1B représentent respectivement un schéma synoptique d'un procédé selon l'invention et un diagramme temporel associé.
• La figure 2 représente un schéma simplifié d'un dispositif pour la mise en oeuvre d'un procédé selon l'invention.
• Les figures 3A et 3B représentent respectivement un diagramme temporel des signaux émis par un équipement individuel selon l'invention, et un schéma de réalisation d'un équipement individuel.
  - Les figures 4A, 4B et 4C représentent respectivement les courbes de tension et de courants I₀, I₁, I₂ , I₃ et les signaux associés S₂₀, S₂₁, S₂₂, S₂₃; un shéma de réalisation d'un analyseur pour indiquer la nature des défaillances des sources; et un diagramme temporel associé.
• La figure 5 représente un schéma de réalisation d'un équipement central d'un dispositif selon l'invention.

We will now describe, by way of nonlimiting example, a particular embodiment of the invention with reference to the appended drawings in which:

• FIGS. 1A and 1B respectively represent a block diagram of a method according to the invention and an associated time diagram.
• FIG. 2 represents a simplified diagram of a device for implementing a method according to the invention.
• FIGS. 3A and 3B respectively represent a time diagram of the signals emitted by an individual device according to the invention, and a diagram of embodiment of an individual device.
  - Figures 4A, 4B and 4C respectively represent the voltage and current curves I₀, I₁, I₂, I₃ and the associated signals S₂₀, S₂₁, S₂₂, S₂₃; an implementation diagram of an analyzer to indicate the nature of source failures; and an associated time diagram.
• FIG. 5 represents a diagram of an embodiment of central equipment of a device according to the invention.

• attendre un intervalle de temps prédéterminé T_o après la mise sous tension, ce temps étant choisi de façon à ce que toutes les sources de rayonnement fonctionnant normalement soient allumées;
• envoyer un signal d'interrogation S₁ à la pluralité d'équipements individuels associés à la pluralité de sources de rayonnement;
• attendre un temps T_n à partir de l'apparition de S₁.
• émettre à l'expiration du temps T_n un signal S₂ caractérisant l'état de la source;
• après interrogation de tous les équipements individuels de la pluralité, attendre l'expiration d'un intervalle de temps prédéterminé T_p ,et recommencer une nouvelle séquence d'interrogations.

With reference to FIG. 1, a method for monitoring an ordered plurality of light radiation sources comprises the following steps:

• wait for a predetermined time interval T _o after switching on, this time being chosen so that all normally operating radiation sources are switched on;
• sending an interrogation signal S₁ to the plurality of individual devices associated with the plurality of radiation sources;
• wait a time T _n from the appearance of S₁.
• emit at the end of time T _n a signal S₂ characterizing the state of the source;
• after interrogation of all the individual equipments of the plurality, wait for the expiration of a predetermined time interval T _p , and start a new interrogation sequence.

The signals S₂ emitted by an individual device can be a normal operating signal S₂₀ or a signal different from said signal S₂₀ such as S₂₁, S₂₂, or S₂₃.

The different signal S₂₃ is for example an absence of signal (zero signal).

Preferably, the signals S₂ relating to a given radiation source are transmitted over a supply line to said radiation source.

In the time diagram of FIG. 1B, in the case of five sources associated with five individual items of equipment EI, each individual item of equipment emits a signal S₂ corresponding to a given radiation source during a predetermined time interval DT _n . The signal S₁ is emitted at the end of a predetermined time interval, T₀ just after powering up the network or T _p between two consecutive scanning cycles. The signal S₂ for normal operation or for failure is emitted after a time T _n after the appearance of the signal S₁, a function of the sequence number n of the radiation source within the plurality of sources. To allow independent and not simultaneous transmissions, the transmission time DT _n of an equipment E _n must be such that the emission of EI _n is completed before the equipment transmitting directly after EI _n has started to transmit. For example, the predetermined time intervals DT _{n are} all chosen to be equal to each other and with the same transmission duration DT. The frequency of the power supply network is advantageously used to define the time intervals, T _n , DT. The signals S₁ and S₂ are advantageously monofrequency signals of respective different musical frequencies F₁ and F₂.

With reference to FIG. 2, the signals S₂ relating to sources 1 of given radiation SR are transmitted by individual equipment 2 EI. on the supply line 3 of said radiation source 1. These signals S₂ are transmitted on said supply line 3 and received at a point on said line distant from said source by central equipment 4 EC. The central equipment 4 EC is preferably located in the cabinet 5 for supplying electrical power to a plurality of sources. In the event of a fault or abnormal operation of a source 1, the signals S₂ are identified and stored at the level of the central equipment 4 EC to be transmitted to a central intervention station 6 PCI by telecommunication means 7, by for example, by telephone line. This transmission to the central intervention station 6 is carried out systematically, for example once a day, but also on request transmitted from the central intervention station 6.

Each source 1 of radiation SR is generally protected by an individual protection device 8, in accordance with the rules of the art governing public lighting installations. This individual protection device 8 comprises, for example, fuses. Advantageously, the device 8 can be placed downstream of the individual equipment 2, as shown. This arrangement makes it possible to simultaneously protect a radiation source 1 and associated individual equipment 2.

With reference to FIG. 3A, an emission time interval DT common to a plurality of individual items of equipment has been chosen equal to the period of the power supply voltage E, represented by curve 9. In correspondence with the curve 9 we see, in the case of a radiation source constituted by a discharge lamp, four different types of signals S₂. The signal S₂₀ (curve 10) corresponds to the normal operation of a live source. The signal S₂₁ (curve 11) corresponds to the case of the breakdown of the lamp. The signal S₂₂ (curve 12) corresponds to a fault in the capacitor associated with the lamp. The signal S₂₃ (curve 13) corresponds to cases distinct from the preceding cases, for example: individual equipment out of use, individual protection triggered, absence of voltage, etc.

As mentioned previously, the individual equipment determines the nature of the fault and consequently chooses the type of signal S₂ to be sent for example from the aforementioned signals S₂₀, S₂₁, S₂₂, S₂₃.

The signal S₂₁ indicates normal operation of both the radiation source and the individual equipment.

The method according to the invention making the individual equipment emit when everything is normal, thus makes it possible to test the operation of the individual equipment while ensuring the protection of said individual equipment by the source protection devices already installed.

With reference to FIG. 3B, individual equipment 2 associated with a source 1 of SR radiation is connected between said source 1 and the individual protection device 8. This individual equipment 2 comprises a receiver 14 of an interrogation signal S₁ emitted by a central equipment EC not shown.

On receiving the signal S₁, the receiver 14 transmits a logic signal in the direction of the counter 15. As soon as the logic signal is received, the counter 15 counts the time T _n allocated to the individual equipment, This time T _n is for example equal double the period of the power supply by the serial number of the individual equipment.

During this countdown, the analyzer 16 compares the voltage U supplying the light source 1 with the current I flowing through it to deduce the value of the phase angle therefrom. This phase angle varies characteristically as a function of the different types of failure. Depending on this comparison, the analyzer 16 therefore chooses the type of signal S₂ to be emitted from the aforementioned signals S₂₀, S₂₁, S₂₂, S₂₃.

The counter 15 and the analyzer 16 transmit two logic signals entering a logic gate 17. When the time T _n has elapsed, the signal S₂ to be transmitted is identified and the logic gate 17 controls the transmission means 18 for transmitting the signal S₂ chosen on the supply line.

As shown in FIG. 3A, in the event of a failure of the radiation source, the signal S₂ distinct from S₂₀ indicates the nature of the failure and therefore characterizes the state of the radiation source 1 of the individual equipment 2. A power supply 18 provides the necessary voltages for electronic circuits.

In the case where the signals S₁ and S₂ are monofrequency signals of respective frequencies F₁ and F₂, capacitors 20A and 20B are connected in series with the receiver 14 and the transmitter 18 respectively. A filter 21 blocks the emission of the frequencies F₁ and F₂ to the radiation source, and, in the case of a discharge lamp, to the capacitor rectifying the power factor.

With reference to FIG. 4A, we can see, represented with respect to the same voltage curve U of electrical supply, the shapes of the curves I₀, I₁, I₂, I₃ of current in dashed lines as well as the signals S₂₀, S₂₁, S₂₂ , S₂₃ in bold lines for various cases of operation of the radiation source.

The curve I₀ corresponds to the case of normal operation of the radiation source; the signal S₂₀ (curve 10) is emitted by the transmitter 18.

The curve I₁ corresponds to the case of a breakdown of a discharge lamp; the signal S₂₁ (curve 11) is emitted by the transmitter 18.

The curve I₂ corresponds to the case of a capacitor out of use; the signal S₂₂ (curve 12) is emitted by the transmitter 18.

The curve I₃ corresponds to the case of an absence of current; the signal S₂₃ (curve 13) emitted by the transmitter 18.

With reference to FIG. 4B, a diagram of an analyzer 16 according to the invention capable of producing a signal indicating the nature of the failure of a radiation source is described. This analyzer is able to indicate the nature of the failures and this analysis is thus carried out at the location of the individual equipment and of the associated light source, that is to say locally. The supply voltage U and the current I passing through the radiation source 1 are transformed by the resistors 22, 23, 24 into voltage u image of U and current i image of I. The image current i is injected into the input of an electronic amplifier 25. The image voltage u is injected at the input of an electronic amplifier 26. These two amplifiers are saturated and produce at their output a square signal v and a square signal j shown in bold in the figure 4C and associated with the curves of u and i shown in dotted lines in the same figure. The comparison of the rising edges of the normalized signals j and v in the comparator 27 makes it possible to qualify the nature of the failure and to produce the appropriate signal S₂ for example the signal S₂₀ represented in FIG. 4C by the curve 10 which will be transmitted during the time interval DT by the transmitter 18. The transmitter 18 transmitting the signal S₂ is for example a single frequency oscillator and transmits for each type of signal a characteristic periodic emission, for example of different durations or different amplitudes, or a combination such variations. As a variant, it is possible to use a frequency characteristic of the type of faults to be reported, by choosing instead of a single frequency F₂, four different frequencies F₂₀, F₂₁, F₂₂, F₂₃. The choice of F₂₃ is justified if it is possible to connect emergency or test supplies to individual equipment, for example autonomous batteries.

With reference to FIG. 5, an embodiment diagram of a central equipment item 4 according to the invention is described. In this example, the central equipment corresponds to a three-phase distribution. Three protection devices 28, for example filters protect the supply network 3 electric music frequency broadcasts. Three capacitors 29 allow the connection to the network of the transmitter 30 of the signal S₁, and of the receiver 31 of the signal S₂. Central equipment 4 also includes a microprocessor 32 with several outputs. A first output of the microprocessor 32 controls the emission by the transmitter 30 of the signal S₁. An input of the microprocessor 32 receives from the receiver 31 of the signal S₂ logic information identifying precisely the type of failure of the source or indicating the proper functioning of the source. A clock 33 controls the scanning cycle of the microprocessor. Preferably this clock is synchronized by reference to the period of the network supply voltage. Thanks to the clock 33 and to the information stored in a memory 34, the microprocessor 32 counts the pulses which allows it to identify a source by counting down the time T _n corresponding to the order number n of a given source. The reception of the logic information coming from the receiver 31 of the signal S₂ allows it to know the state of the source. The microprocessor 32 can store all of the information corresponding to the state of a plurality of sources in an erasable memory 35. At the chosen time, information relating to the situation of the sources 1 of the the area he is responsible for controlling. It should be noted that, for a plurality of sources not exceeding the capacities of the microprocessor 32, the memories 34 and 35 are optional.

The method and the device according to the invention thus make it possible to scan the state of a plurality of light radiation sources by interrogating according to a first ordered scan cycle of the individual devices each associated with a radiation source and to cause these devices to be emitted according to a second cycle ordered towards the central equipment to which they are connected. Each individual device transmits during a predetermined time interval so as not to overlap the emissions of two separate individual devices.

Individual equipment is further protected by individual protection devices from light sources, without incurring additional costs. Individual equipment is continuously monitored, since their failure results in the emission of a signal S₂₃ or the like.

The individual equipment is switched on and off by switching the supply network on or off from a power supply cabinet serving a plurality of sources: monitoring under power is therefore permanent and automatic. As this monitoring is permanent, any event is reported as soon as it occurs. We can therefore date and memorize all the events corresponding to a failure: this makes it possible to develop reliable and precise statistics to optimize the management of the lighting network.

Without departing from the scope of the present invention, additional analysis means can be added to finely analyze the type of failure and involve the appropriate intervention means. In particular, different frequencies can be used, each characterizing a particular type of failure, or by using a given frequency, modulating the failure signal to provide additional information.

Claims (12)

Method for monitoring at least one source (1) of light radiation connected to a supply network, characterized in that it comprises at least one step consisting, using individual equipment (2) associated the radiation source (1) to detect the normal operation of the radiation source (1) and to emit a normal operation signal (S₂₀), and, in the event of a failure or abnormal operation, to transmitting a different signal (S₂₁, S₂₂, S₂₃) from said normal operating signal (S₂₀), said different signal possibly consisting of an absence of signal (S₂₃). Method according to claim 1, characterized in that the signals (S₂) relating to the radiation source (1) are transmitted on a line (3) supplying said radiation source (1) and received, at a point from said line (1) remote from said source, by central equipment (4). Method according to claim 2, characterized in that an individual device (2) emits a signal (S₂) corresponding to a given source (1) of radiation during a predetermined time interval (DT). Method according to one of claims 1 to 3, for monitoring an ordered plurality of sources, characterized in that the signal (S₂) of normal operation or of failure, is emitted after the expiration of an interval of predetermined time (T₀, T _p ) then a time interval (T _n ), function of a sequence number (n) of the radiation source (1) within said plurality of sources. Method according to any one of Claims 1 to 4, characterized in that the said different signal (S₂₁, S₂₂, S₂₃) indicates the nature of the failure of the radiation source (1). Method according to any one of Claims 1 to 5, characterized in that the signals (S₂) capable of being emitted by a given individual item of equipment (2) are signals of musical frequency (s). Method according to any one of Claims 2 to 6, characterized in that the signals (S₂) relating to a given source (1) of radiation are, in the event of failure or abnormal operation, identified, stored and transmitted to a central intervention station (6) preferably by telephone line (7). Device for monitoring at least one source of light radiation, characterized in that it comprises individual equipment (2) associated with a source (1) of radiation, for emitting a normal operating signal (S₂₀) from said source and a different signal (S₂₁, S₂₂, S₂₃) from said normal operating signal in the event of abnormal operation or failure of said source, said different signal possibly consisting of an absence of signal, and by the fact that an item of equipment (2) individual is protected by at least one protection device (8) associated with a radiation source (1) which simultaneously protects said individual equipment (2) and said radiation source (1). Device according to claim 8, characterized in that it comprises central equipment (4) connected to at least one individual equipment (2), by a line (3) supplying said source (1). Device according to claim 9 for monitoring an ordered plurality of sources, characterized in that it comprises scanning means (30,31,32,33,34,35) for interrogating by means of a signal ( S₁) of the individual items of equipment (2) and having them emitted according to an ordered cycle (T _n , DT) in the direction of the central item of equipment (4) to which they are connected, each individual item of equipment (2) emitting during a time interval ( DT) determined so as not to overlap the emissions of two separate individual pieces of equipment (2). Device according to any one of Claims 8 to 10, characterized in that the individual equipment (2) is capable of transmitting a different signal (S₂₁, S₂₂, S₂₃) according to the nature of the abnormal operation or of the failure of said said source (1). Device according to any one of Claims 8 to 11, characterized in that it comprises dating (33), storage (34,35) and transmission (7) means at a central station (6). intervention by telecommunication means, preferably by telephone line (7).

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