FR2848008A1 - Electrical conductor events e.g. lightning strike monitoring device, has stamping unit for time stamping of events and display unit to display information regarding intensity and time of occurrence events on screen - Google Patents

Abstract

The device has a sensor (40) arranged in a case (2) and a counter (43) to count events. The case has a stamping unit for time stamping of a set of events stored in a memory. Information regarding intensity and time of occurrence of the events are transmitted to a visualization and display unit (44) for displaying the information on a screen (3) of a liquid crystal display.

Description

i

  EVENT TIMING DEVICE. GENERAL TECHNICAL AREA.

  The present invention relates to autonomous devices for monitoring physical events.

  More specifically, it relates to autonomous devices for monitoring and time stamping events in an electrical conductor.

STATE OF THE ART.

  Means and devices for monitoring physical events are already known in the prior art, making it possible, in particular, to detect and count a certain number of physical phenomena.

  The physical phenomena that one seeks to observe and count are, for example, changes in the magnetic field or the electric field within a given perimeter, or also changes in the intensity of the current flowing through an electrical conductor.

  The detection and the counting of these physical events can have a scientific interest of course, but also an interest for the insurance or maintenance companies for example. Indeed, 20 some insurance companies want to ensure that certain material damage declared by their customers has been caused by an alleged physical event, and not by negligence on the part of their customer.

  This is particularly the case for damage caused by lightning.

  Still in this particular application given by way of example, the observation and counting of lightning strikes can also be useful for the maintenance of a certain number of devices, in particular lightning conductors or lightning arresters.

  Figures 1 and 2 schematically represent examples of known devices for detecting and counting lightning strikes.

  Such a detection and counting device 1 mainly comprises a box 2 mounted on an electrical conductor, generally a downward conductor of lightning conductor 4. It is recalled that a lightning conductor 4 is a device for protection against atmospheric discharges comprising, in general, one or more rods or points, earth connections and down conductors bringing these elements together. The lightning rod is therefore referenced by 4 in all of the figures in this description. It extends vertically 5 in order to be able to attract lightning at its top, which does not fall on the building on which it is placed.

  The device 1 includes display and display means 3 making it possible to display the number of lightning strikes which have struck the lightning rod 4.

  The housing 2 has substantially a parallelepiped shape. A front wall 11 and a rear wall 12 which extend vertically are defined on the housing 2. The housing 2 is fixed to the lightning rod 4 by fixing means referenced by 5 in FIGS. 1 and 2 and mounted on its rear wall 12. The means 5 form a flange mainly comprising a plate enclosing the lightning rod 4 between the plate 5 and the wall 12 of the housing 2. The flange 5 is fixed to the housing by fixing means 20 visible in FIG. 2. The fixing means 20 comprise for example screws.

  Thus, when the housing 2 is in position on the lightning rod 4, the latter extends between the wall 12 of the housing 2 and the plate of the means 5. The wall 12 and the plate are substantially parallel with respect to the 'other.

  The display and display means 3 are generally located on the front wall 11 of the housing 2.

  During a discharge caused by lightning striking the top of the lightning conductor 4, the electric overcurrent moves in the down conductor of the lightning conductor 4 towards the earth connection generally situated on the ground. The current therefore flows in the lightning rod 4 in the direction referenced by 10 in FIGS. 1 and 2.

  The device 1 detects the overcurrent during its passage through the conductor 4. It increments a counting device, which therefore makes it possible to determine the number of lightning strikes which have struck the lightning rod 4 since the device was put into service on the lightning rod.

  The principle diagram for detecting the passage of current in the lightning conductor 4 is shown diagrammatically in FIG. 3.

  During the passage of an overcurrent represented by 30, there is creation of a magnetic field 31 winding around the overcurrent 5 in a clockwise direction for a falling intensity. This winding is known by the skilled person as the "right hand theorem". The magnetic field flux variation is then detected through a window 32 or a detector. The flux variation is detected because it itself creates an induced current, the intensity of which can be measured. By knowing the induced current, we can go back to knowing the current overcurrent, these two currents being linked by the characteristics of the conductors in the circuit.

  FIG. 4 shows the various elements constituting the device 1 according to the prior art.

  Figure 4 shows schematically in a longitudinal section the autonomous unit 2 comprising a block 40 for detecting a physical event, that is to say the passage of an overcurrent in an electrical conductor in the example of lightning conductors. The detection block is located near the rear wall of the housing 2 and near the conductor 4, in order to ensure better detection of the event. Block 40 detects the event and transforms it into an electrical signal.

  A block 41 for conditioning the signal detected at 40 is connected at the output of block 40.

  A comparator block 42 connected at the output of block 41 makes it possible to compare the signal with a predetermined threshold.

  When the signal at the output of block 41 is larger than the predetermined threshold and fixed in block 42, a counter 43 is then incremented located at the output of comparator block 42.

  There is then the display of the information from the counter 43 on 30 of the display and display means 44, which are connected to a display screen 3 on the front face 11 of the housing 2.

  The components of the different blocks of device 1 are such that device 1 can meet the UTE C 17-106 standard. In particular, the standard defines that the orders of magnitude of the detected overcurrents are 1 kA.

  The prior art has been described more precisely for lightning strike counters, but of course, there are also devices for detecting overcurrents in any electrical conductor, for example an overcurrent with respect to a useful signal in a communication network. The only difference is then the sensitivity of the block 40 as well as the increment threshold of the counter 43.

  Other events can also be detected, such as variations in the magnetic or electric field according to techniques known to those skilled in the art.

  The devices of the prior art do not however bring total satisfaction. It can be seen that, despite their practical interest, the monitoring devices described above have not experienced the expected industrial development. PRESENTATION OF THE INVENTION.

  The invention proposes to improve the situation and to propose a device having advantages over the prior art.

  To this end, the invention provides an autonomous device for monitoring events in an electrical conductor comprising an event sensor disposed in a housing and means for counting events, characterized in that the housing comprises storage means and time stamping of a set of events and means 25 for displaying and displaying on said housing the time stamping of events of the set.

  Thus, while in the state of the art, the information displayed on the box only gives information on the number of events which has been observed, the present invention makes it possible to know when the various events have happened.

  In particular, for insurance, to know if the damage declared by one of their insured is really due to a thunderbolt, the present invention makes it possible to precisely date the event to verify the declarations, and to correlate the information with weather reports by example.

  Likewise, the invention makes it possible, for maintenance procedures, to be able to date the event. Indeed, certain maintenance procedures must be carried out within a certain time following an event, such as a lightning strike.

  We note that by set of events, we mean a succession in time of physical events of the same nature.

  The invention is advantageously supplemented by the following features, taken alone or in any of their technically possible combinations: - it includes means capable of allowing a user to scroll through the set of events to view an event selected on the display means; the display means are capable of displaying the rank, the year, the month, the day, the hour and the minute of the occurrence of each event; - It includes means for sending a signal out of the housing upon the occurrence of an event; the sending means comprise means generating a light signal and an optical fiber transporting said light signal out of the housing; - It includes means for adjusting time stamping means; - It includes autonomous power supply means; - the events to be time-stamped are overcurrents on the driver; the event sensor comprises an electronic circuit forming an inductor comprising at least two circuits connected in series; and - it comprises means capable of displaying on the housing the charge and / or the intensity having passed through the conductor during the event.

  It is thus found that the device is autonomous in supply and in a state of electrical potential with respect to the outside world.

PRESENTATION OF THE FIGURES

  Other characteristics, objects and advantages of the invention will emerge from the description which follows, which is purely illustrative and not limiting, and which should be read with reference to the appended drawings in which: - Figures 1 and 2, already commented on, schematically represent a device for detecting and counting lightning strikes according to the state of the art; - Figure 3, already discussed, schematically shows the principle of detecting an overcurrent passing through a conductor; - Figure 4, already commented, schematically shows the functional blocks included in a device housing according to the prior art; - Figure 5 schematically shows a possible assembly of an embodiment according to the invention; - Figure 6 schematically shows an advantageous embodiment of a magnetic field sensor disposed in a device according to the invention; - Figure 7 schematically shows a possible embodiment of a housing according to the invention; and - Figure 8 schematically shows all the blocks that can be arranged in a housing of a device according to the invention.

DETAILED DESCRIPTION.

  FIG. 7 schematically represents a possible embodiment of a device 1 for detecting, counting and time stamping 25 physical events according to the invention. The means substantially identical to those of FIGS. 1 to 4 and fulfilling the same functions bear the same numerical references.

  FIG. 7 shows that the device 1 mainly comprises a box 2 of substantially parallelepiped shape having on a front face 30 of vertical extension 11 means 3 for displaying and displaying information relating to detection, counting or time stamping physical events. The means 3 comprise for example a liquid crystal screen.

  A rear face 12 opposite the front face 11 comprises means for fixing to an electrical conductor 4. The fixing means are referenced by 5 in FIG. 8, which is a schematic longitudinal section of the device 1 and of the functional blocks located at the inside the housing 2. The fixing means 5 are almost similar to those described above in the prior art. They comprise a plate forming a flange and means for fixing the flange to the rear wall of the housing, comprising for example screws.

  They make it possible to fix the device 1 to the conductor 10 4 in an insulating manner. They thus guarantee the autonomy of the system. The term "autonomy" means autonomy both in supplying power to the various components constituting the device 1, and autonomy in the potential of the device 1. In fact, the device 1 is not connected to any external conductor. It is not part of any electrical circuit. This is why it can be mounted, thanks to an insulating connection, on lightning conductors 4 which are crossed by very high electrical currents. The device 1 is electrically isolated from the outside world and is not likely to be crossed by a strong current which could damage it or damage elements of a circuit in which it would be mounted.

  The detector 40, processing 41, comparison 42, counting 43 and display 44 blocks fulfill the same general functions as in the device of the prior art.

  FIG. 8 thus shows that the housing 2 comprises, near the rear wall 12 of the housing 2 and of the conductor 4, a block 40 for detecting a physical phenomenon the output of which is connected to means 41 for processing the signal electrical from sensor 40, in order to be able to inject the signal into a comparator block 42 which compares the value of the electrical signal to a predetermined threshold depending on the chosen application.

  If the value of the signal is greater than the threshold, then a counter block 43 is triggered which increments the number of events which have occurred in the conductor 4, and according to the invention also triggers a time stamp of the event which comes to occur.

  The detection, counting and time stamping information is then sent to the display means 44 and the screen 3 on the front face 11 of the housing 2.

  Thus, the device 1 comprises means making it possible to detect, count and time stamp physical events, such as a variation of a magnetic field, of an electric field, or to detect an overcurrent crossing the conductor 4.

  The following description takes as an example the detection of an overcurrent. This overcurrent can take place on a lightning conductor, on a lightning arrester protecting an electrical installation, a conventional electrical installation, or conductors of telecommunication networks transporting an electrical signal carrying information. Thus the conductor 4 can be of different nature depending on the applications.

  Thus, the device 1 detects an overcurrent with respect to a threshold, the threshold being fixed and predetermined in means 42 visible in FIG. 8.

  FIG. 5 schematically represents an electronic circuit allowing a possible embodiment of the device according to the invention. The circuit of FIG. 5 uses the “surface mounted circuit” or CMS technology according to the terminology generally used by a person skilled in the art. 20 The CMS technology makes it possible to obtain a very flat circuit and obtain a compact housing. It is thus noted that the block 40 mainly comprises a coil making it possible to detect the variation in the flux of the magnetic field created by the overcurrent 30 passing through the conductor 4.

  FIG. 6 shows that the detector unit 40 advantageously comprises a winding forming a coil embodied in the form of printed circuit technology.

  The detector is arranged in an eccentric position relative to the axis of the conductor 4. Such a position avoids the compensation of the fluxes 30 entering and leaving the coil, compensation which occurs if the detector is centered relative to the axis connector 4.

  Advantageously and as shown in FIG. 6, the sensitivity of the block 40 is increased by mounting in series at least two coils 61 and 62 of the same type and offset relative to the axis 30. The two coils 61 and 62 are mounted in series , but the winding direction of the coils of each coil is symmetrical to that of the other coil with respect to a plane passing through the axis 30 and perpendicular to the plane passing through the coils 61 5 and 62. A coil has its coils winding clockwise, the coil connected in series has its windings winding counterclockwise. Thus, the magnetic field fluxes do not compensate for each other. The entire block 40 can therefore be centered on the axis 30.

  Advantageously, the circuit comprises four coils mounted in series and whose winding directions are symmetrical with respect to the axis. The circuit then comprises two coils on each surface of the plate on which it is mounted.

  The block 41 mounted at the outlet of the block 40 mainly comprises a diode bridge making it possible to rectify the signal, and thus to detect an overcurrent whatever its direction of passage in the conductor 4.

  The circuit of FIG. 5 also includes a block 55 intensity limiter leaving the block 40. It is on the one hand connected to the outlet of the block 40 and on the other hand connected to the inlet of the block 41. It thus protects the entire circuit downstream of it.

  The block 41 therefore processes the signal in order to be able to inject it into the block 42 which mainly comprises a capacitor C1 of which the charge and the discharge are measured in a resistor R3.

  The block 42 also includes a Zener diode DI mounted in parallel with the resistor R3 and which performs the function of clipping the electrical signal from the charging and discharging of the capacitor C1.

  The output of the diode D1 is connected to elements forming logic gates 56, 57 forming comparator at a predetermined threshold. Thus, as a function of the signal level at the output of block 41, the logic elements 56 and 57 provide an instruction to an assembly 58 forming an integrated circuit 30 forming a counter and a time stamp, in particular having moreover an integrated clock which makes it possible to time stamp each event. .

  If the signal at the output of block 41 is less than the threshold, then the assembly 58 does not count any additional event.

  If, on the other hand, the threshold is exceeded, the logic elements 56 and 57 deliver to the assembly 58 a signal capable of incrementing an event counter. The information recorded by all of the integrated circuits 58 5 is then transferred to the display block 44. The block 44 transmits to the screen 3 located on the wall of the housing 2 for its display for a user.

  The display includes information concerning the rank 50 of the event in the set of detected events, information 51 concerning the year of the event, information 52 concerning the month of the event, information 53 concerning his day, as well as the hour and the minutes in 54 at which it occurred.

  The set 58 of integrated circuits can detect x events and display one by one y events. X and y can be equal, but can for example be equal to 100 and 10 respectively.

  FIG. 7 shows that the scrolling of the information on the display means 3, in particular the display of the events y according to their rank, is carried out by means 6 fixed on a wall of the housing 2. The means 6 allow a user to scroll through the events recorded on the display and include, for example, a press button. Advantageously, the press button is fixed under the lower wall of the housing 2 so as not to be sensitive to bad weather.

  Advantageously, the device 1 comprises means allowing the adjustment of the time stamping means included in the assembly 58.

  In particular, the adjustment means comprise means for setting the time of the internal clock and the date counted by the assembly 58. The adjustment means can be combined with the means 6 for scrolling events, or have a separate push button fixed to a wall of the housing 2. As a variant, it may be a magnetic actuator which acts through the housing, for controlling a Reed type bulb for example. The protocol for adjusting the time stamping means is conventional and is carried out, for example, by pressing on the adjustment means. In a variant, it is also possible to provide devices allowing synchronization of the time stamping means with respect to a high precision clock, by radio electric means for example. Thus, the device always remains on time and a very high time stamping precision is obtained, without a user needing to reset the device after a clock drift in time. Advantageously, resetting the event counter to zero is impossible by a user, and can only be carried out by returning to the factory and dismantling the device. This avoids abuse by malicious people, who would not have performed maintenance actions after an event for example, and who would like to erase the traces of this omission.

  Advantageously also, the box 2 can comprise means making it possible to send a signal out of the box 2 during the occurrence of an event. This signal makes it possible to warn an outside person during the occurrence of an event, for example with a view to maintenance in a time relatively close to the event.

  The sending means comprise for example means sending a radio signal. Preferably, the sending means comprise a light generator and an optical fiber 7 sending a light signal 20 outside the housing 2 to warn a person, or trigger a device remotely. This device 7 for sending the signal out of the housing 2 is preferably in optical form, in order to maintain the characteristic of autonomy of potential and of isolation of the device 1 from the outside world.

  It should be recalled that the term “autonomy” means an autonomy of electrical supply as well as an autonomy of electrical potential, that is to say that the device 1 is not connected to anything electrically and can undergo phenomena or events. of high electrical amplitude without damaging a circuit or an installation located downstream for example.

  Conventionally, to ensure the autonomy of the power supply to the device, it comprises a conventional long-life battery.

  However, it is possible in a variant to provide means 8 forming a solar cell visible in FIG. 7.

  The dimensions of the parallelepiped housing are of the order of 5 cm.

  The housing is waterproof to withstand the most difficult atmospheric conditions.

  According to an advantageous variant, shown diagrammatically in FIG. 8, the device further comprises a block 45 making it possible to store information which is a function of the intensity of the event 30 which takes place in the conductor 4.

  In the example of the present description, it may be the current measured at the output of the detector 40. Thus, knowing the values of the inductances and the mutual between the conductor and the coil, we can go back to the intensity of the current which has passed through the conductor 4. It is also possible, by integrating this value of the current, to go back to the load which created this current.

  Advantageously, this information on the intensity of the event which has occurred in the conductor 4 is transmitted to the display and display means 44 to be displayed on the display screen 3 of the box 2.

  Thus, the housing 2 comprises two main circuits mounted in parallel from the output of the sensor 40. The first circuit is composed of the block (41, 42 and 43) and possibly includes a clipping step at the output of the sensor 40 in order to compare a pulse to a predetermined threshold, for counting and time stamping. The second circuit mainly comprises the block 45 which stores in memory an analog information item at the output of the detector 40 which can subsequently be linked to the value of the intensity of the event.

Claims (10)

CLAIMS.   1. Autonomous device (1) for monitoring events in an electrical conductor (4) comprising an event sensor (40) arranged in a housing (2) and means (43) for counting events, characterized in that that the box (2) comprises means for storing and time stamping a set of events and means (44, 3) for displaying and displaying on said box (2) the time stamping of events of all. 10 2. Device according to claim 1, characterized in that it comprises means (6) capable of allowing a user to scroll through the set of events to view an event chosen on the display means (3).   3. Device according to one of claims 1 or 2, characterized in that the display means (3) are capable of displaying the row (50), the year (51), the month (52), the day ( 53), the hour and minute (54) of the occurrence of each event. 20 4. Device according to one of claims 1 to 3, characterized in that it comprises means making it possible to send a signal out of the housing during the occurrence of an event.   5. Device according to claim 4, characterized in that the sending means comprise means generating a light signal and an optical fiber (7) transporting said light signal out of the housing. 6. Device according to one of claims 1 to 5, characterized in that it comprises means (6) for adjusting the time stamping means.   7. Device according to one of claims 1 to 6, characterized in that it comprises autonomous electrical supply means.   8. Device according to one of Claims 1 to 7, characterized in that the events to be time-stamped are overcurrents on the conductor (4). 9. Device according to claim 8, characterized in that the event sensor (40) comprises an electronic circuit forming an inductor coil 10 comprising at least two circuits forming coils (61, 62) connected in series.   10. Device according to one of claims 8 to 9, characterized in that it comprises means (45) capable of determining and / or displaying on the housing the charge and / or the intensity having passed through the conductor during the event.