Fire safety device for recharging an electric battery

Abstract

The invention relates to a fire safety device (1) for preventing a fire in an electric battery (3) of a vehicle (V), in particular a motor vehicle, which device is capable of being connected to a terminal (2) for supplying electric current by means of a cable (4), the electric current having electrical data, wherein the device comprises at least one connector (10, 11), an appliance for measuring the electrical data detected at the connector, a smart module (7) that compares the measured electrical data with theoretical electrical data stored in a memory (6), a control module (8) capable of receiving an alert signal from the smart module (7) and capable of delivering a control signal (S1) for securing the vehicle, and a transceiver (9) capable of transmitting the control signal to a remote appliance (50) for securing the vehicle.

Description

Description Title of the invention: FIRE SAFETY DEVICE FOR RECHARGING AN ELECTRIC BATTERY FIELD OF THE INVENTION

[0001] The invention relates to the safety of an electric battery charging station, comprising a device which makes it possible to detect a fire risk during the charging of a battery and which in particular makes it possible to make the charging station safe in the event of detection of this risk. The device can also be installed in a charging terminal, or directly in an electronic module integrated directly into the battery STATE OF THE ART

[0002] Electric vehicles pose a significant fire risk, particularly when recharging their batteries.

[0003] Indeed, the risk of self-ignition of lithium batteries increases following a mechanical shock, which can damage the cell envelope that makes up the battery, or during exposure to a strong rise in temperature, or even following an electrical short circuit.

[0004] Such batteries operate optimally when the ambient temperature is between 10°C and 45°C.

[0005] However, their operation deteriorates outside this temperature range: for example, when the ambient temperature is approximately -20°C, a lithium battery loses approximately 60% of its discharge capacity. Thus, faced with excessively low temperatures, the electronic devices of electric vehicles can prevent the use of the batteries in order to preserve them, or at least reduce the discharge current for the same purpose.

[0006] Conversely, when the ambient air temperature is above 45°C, it is imperative to have technical means to reduce the temperature in the vicinity of the battery, for example by ventilating it.

[0007] Above 60°C, in addition to ventilation, it may be necessary to reduce the battery charging intensity or reduce the discharge current.

[0008] Above approximately 75°C, internal damage to the battery is observed, which can lead to its destruction with a risk of self-ignition and then thermal runaway.

[0009] Document WO201512742 discloses a system for thermal management and automatic fire extinguishing of an automobile battery. The system comprises a casing that surrounds the automobile battery and encloses an extinguishing agent. fire. The enclosure is designed to be opened when the battery temperature is above a preset temperature, to release the extinguishing agent onto the battery.

[0010] Document WO2022220366 also discloses an installation that is implemented to prevent the risk of fire spreading: the installation comprises mobile panels that are installed around a vehicle with an electric battery and above it, the panels being put in place when a fire or smoke is detected. The document also provides for the projection of water into the installation, inside the volume defined by the panels, up to knee height, to cool the vehicle and in particular the battery.

[0011] Finally, document WO2022104539 discloses a fire-fighting device capable of releasing a gas capable of fighting a fire and capable of collecting and trapping a combustible gas which is produced by the battery during its thermal runaway. The device also makes it possible to mix the combustible gas and the fire-fighting gas and to evacuate the mixture to the outside.

[0012] Other solutions have also been devised - they all have in common the fact that they offer a solution once the thermal runaway of the battery has been detected, or even after the fire has started.

[0013] The invention aims to propose a solution that intervenes before the thermal runaway of the battery, even before the fire starts. PRESENTATION OF THE INVENTION

[0014] The invention relates to this end to a fire safety device, for preventing a fire in an electric battery of a vehicle, in particular a motor vehicle, said battery being capable of being connected to an electric current supply terminal by means of a cable, said electric current having electrical data,

[0015] said safety device comprising:

[0016] - at least one connection connector, capable of connecting the device to the battery, to said terminal or to said power cable,

[0017] - a device for measuring said electrical data detected at the connection connector

[0018] - an intelligent module which compares the measured electrical data with theoretical electrical data, representative of a theoretical state of charge of said battery as a function of the charging time,

[0019] said theoretical data being recorded in a memory included in said device,

[0020] - a control module which communicates with said intelligent module and is capable of receiving an alert signal from said intelligent module if a discrepancy is observed between the measured electrical data and theoretical electrical data, as a function of the charging time, said difference being greater than a first predetermined value or less than a second predetermined value, said control module being capable of delivering a vehicle safety control signal, and

[0021] - a transmitter / receiver, capable of transmitting said control signal for securing said vehicle to a remote device for securing said vehicle.

[0022] Thus implemented, the device makes it possible to anticipate heating of the battery by monitoring the data which characterizes the electric current during the recharging of the battery, and to implement a preventive action before the battery catches fire.

[0023] Indeed, when a lithium battery is used during its electrical recharge or during its discharge to power electrical equipment, it operates under a well-defined voltage range, generally +25% / -5% of the nominal voltage for each of the cells that make up the battery.

[0024] Outside this recharge or discharge voltage range, the cells are exposed to abnormal operation which can lead to irreversible damage to the battery.

[0025] The device according to the invention may also include the following characteristics, taken separately or in combination:

[0026] - When one of the cells making up the battery is short-circuited due to an inappropriate ambient temperature or a mechanical shock, the said lithium battery produces an electrical peak which is measured by the device as a very strong and brief rise in voltage greater than 25% of the nominal recharge or discharge voltage, allowing the device to identify the short-circuiting of one or more elements making up the battery, thus preventing the imminent thermal runaway of the said battery. This voltage peak is different from those indicating the end of a fast recharge or the end of a slow recharge: thus, the first predetermined value is greater than 25% of the voltage or the theoretical intensity of the battery charge as a function of time and the second predetermined value is -5% of the voltage or the theoretical intensity of the battery charge as a function of time,

[0027] - the memory of the device includes a log in which the electrical data measured as a function of time are recorded, preferably at regular intervals,

[0028] - advantageously, the device comprises a connector allowing it to be connected to an external device in order to collect said data recorded in said log,

[0029] - according to an alternative embodiment, the connection connector comprises a first cable to be connected to said terminal and a second cable to be connected to said battery,

[0030] - according to another embodiment variant, the connection connector comprises a first socket which connects to said terminal or to said battery, and a second socket to which said cable is connected.

[0031] The invention also relates to a vehicle battery, in particular an automobile battery, which is associated with a device as defined above.

[0032] The invention also relates to a charging terminal which is associated with a device as defined above.

[0033] The invention also relates to an installation comprising a vehicle battery, in particular an automobile battery, a charging terminal for said battery, a cable for connecting said terminal to said battery and a device as defined above.

[0034] The invention also relates to a charging station for a vehicle battery, in particular a motor vehicle, comprising at least one installation as defined above and a remote safety device.

[0035] The invention also relates to a method for preventing a fire in an electric battery of a vehicle, in particular a motor vehicle, using a device as defined above, said method comprising the following steps:

[0036] - measurement of said electrical data detected at the connection connector of said device,

[0037] - comparison of the measured electrical data with theoretical electrical data, by said intelligent module, and

[0038] - transmission to the control module of an alert signal if the intelligent module detects a discrepancy between the measured electrical data and the theoretical electrical data, as a function of the charging time, said discrepancy being greater than a first predetermined value or less than a second predetermined value,

[0039] - delivery, by said control module, of a vehicle safety control signal, or a specific voltage peak as described above,

[0040] - reception of said control signal by a remote safety device of said vehicle and triggering of the safety device.

[0041] Furthermore, in the case where the method according to the invention implements a fire safety device associated with a battery, characterized in that the safety device is an electronic control unit of the vehicle, and in that the triggering of the safety device leads in particular to reducing the speed of said vehicle until it stops.

[0042] In the case where the method according to the invention is implemented in an installation according to the invention and defined above, the remote device for securing said vehicle comprises at least one fire- and smoke-tight closing curtain for an entrance to said station, said curtain being mounted to move between an open position and a closed position, and the triggering of the safety device causes the curtain to move from the open position to the closed position of said entrance .

[0043] The fire safety of the electric vehicle charging area, delimited by the frame and the fire-resistant curtain(s), can be remotely controlled by the device of the invention, or self-controlled by the rupture of a thermal fuse following the abnormal rise in the ambient temperature of the charging area, thus controlling the closure by intrinsic energy of the fire-resistant curtain(s).

[0044] The method according to the invention may also comprise an additional step of recording the measured electrical data in the memory of said device.

[0045] Finally, the method may advantageously include a step following which the measured electrical data is transmitted to a remote server of a fire safety monitoring unit. PRESENTATION OF FIGURES

[0046] Other advantages and characteristics of the invention will appear on examining the detailed description of a non-limiting embodiment, and the appended drawings, in which:

[0047] [Fig.l] is a schematic representation of a safety device according to the invention, as well as a charging terminal connected to a battery by a power cable,

[0048] [Fig.2] is a schematic representation of a first embodiment of an installation in accordance with the invention,

[0049] [Fig.3] is a schematic representation of a second embodiment of an installation according to the invention,

[0050] [Fig.4] is a schematic representation of a third embodiment of an installation according to the invention, and

[0051] [Fig.5] illustrates an electric vehicle battery charging station according to one embodiment of the invention, seen in perspective.

[0052] DESCRIPTION OF AN EMBODIMENT

[0053] The device according to the invention is designed to detect the imminent ignition of a battery and to secure the site where the battery is located (charging station, or even the vehicle alone containing the battery). The invention makes it possible to identify an event which occurs just before the ignition of the battery in order to avoid it, or following an increase in the ambient temperature of the charging station >70°C.

[0054] [Fig.l] schematically represents an embodiment of a device 1 in accordance with the invention:

[0055] The device 1 is designed to be positioned between a charging station 2 and an electric battery 3.

[0056] The electric battery 3 may be a Lithium battery, designed to be implemented in a motor vehicle, a vehicle with two or three wheels, or any other vehicle equipped with an electric battery requiring recharging.

[0057] Conventionally, said battery 3 is designed to be connected to the power supply terminal 2 by means of a cable 4, in order to be recharged.

[0058] The device according to the invention can be positioned either at a connector 20 of terminal 2 (see [Fig.4]), or at a connector 30 of the battery (see [Fig.3]), or on the connection cable 4 (see [Fig.2]): in this case, the device 1 is equipped with two connection cables 4, one of the cables connecting to the connector 20 of the charging terminal and the other connecting to the connector 30 of the battery 3 to be recharged.

[0059] To enable this connection, the device can itself be equipped with sockets 10 and 11, including a socket 10 which connects directly to the connector 20 of the charging terminal 2 or to the connector 30 of the battery, and a socket 11 which allows the connector located at the end of the connection cable 4 to be connected.

[0060] The device 1 could also be designed to be integrated into the charging station 2 or the battery 3, this embodiment hiding the device 1 from the public.

[0061] Thus connected to the charging terminal, to the battery or to the connection cable, the device 1 can measure data relating to the electric current which circulates between the charging terminal and the battery through the connection cable 4, or the data relating to the electric current at the output of the charging terminal 2 or even to the terminals of the battery 3.

[0062] Data relating to electrical currents are, for example, voltage, power or current intensity.

[0063] To measure the data relating to the electric current, the device 1 comprises a measuring device 5, which measures the electrical data received at the socket 10 and / or 11 or directly at the terminals of the battery or in the charging station if the device 1 is directly integrated into the terminal 2 or the battery 3.

[0064] The device 1 also comprises, in accordance with the invention, a memory 6, which comprises at least:

[0065] - a log 60, in which are recorded, for example at regular time intervals, the data relating to the electric current and which are measured by the measuring device 5, and

[0066] - a set of theoretical data, previously recorded in a memory part 61, which corresponds to a set of charging data that could or should normally be observed during a battery recharge or during a discharge of battery.

[0067] This set of theoretical data depends on the type of battery to be recharged and is recorded prior to any use of the device 1. It can also be updated, in a manner known to those skilled in the art, for example by equipping the device with an update control unit and by equipping the device with a USB port or an antenna connected to the low-frequency Lora or Wifi network, allowing the updating of the data in the memory part 61 as well as the transmission of this data locally via a USB, Bluetooth or WIFI port, or remotely via the Internet or via the Lora communication protocol, in particular.

[0068] It should be noted, in fact, that depending on the type of Lithium battery and its capacity, recharging must be done more or less according to a predetermined model: for example, initially, the power of the electric current transmitted to the battery by the terminal has a high current intensity, to allow the battery to be recharged as quickly as possible, in a limited time interval. In fast charging, we can expect the battery to be recharged to 80% of its capacity in a time between 20 minutes and 2 hours, for a battery that normally charges completely in a time interval between 8 and 12 hours. Once 80% charge is reached, the battery recharge switches to slow charging, with a constant voltage, in particular to limit the rise in temperature of the battery 3.

[0069] The battery charge level is identified by an electronic system included in the terminal and / or in the device according to the invention.

[0070] When charging the battery, the theoretical data of the memory part 61 are compared with the electrical data measured by the device 1 using an intelligent module 7.

[0071] The intelligent module 7 is capable of detecting whether the power, voltage or current intensity corresponds to substantially more or less than 25% (or corresponds to more or less 25%) of the theoretical power, voltage or current value which should be observed depending on the charging time.

[0072] The smart module is also able to detect if the charging power, voltage or current intensity is less than -5% (or significantly less than 5%) of what should be observed during battery discharge.

[0073] In fact, the intelligent module 7 also takes into account the discharge of the battery 3 which occurs when the battery is fully charged and which allows the battery to be left connected to the charging station without the battery 3 being damaged or without it overheating.

[0074] If the intelligent module detects variations greater than 25% during charging (or -5% during discharging), or even peaks in voltage or intensity or power delivered, then it transmits an alert signal to a control module 8, which also comprises the device 1 according to the invention, which can control a preventive action on the battery, on the vehicle comprising the battery or on the installation comprising the charging terminal to prevent the battery from catching fire and before the battery catches fire.

[0075] To do this, the control module 8 communicates with a fire safety system (for example) or any other safety device of the vehicle which includes the battery, this safety device being remote from the device 1.

[0076] This communication can be done by Wifi, LoRa Wan technology or Bluetooth, in a manner known per se, thanks to a transmitter / receiver 9 which the device 1 also includes (see [Fig.1]).

[0077] The transmitter / receiver 9 can also be used to remotely transmit the data recorded in the data log 60.

[0078] It should be understood that the current data that is recorded in the log could be retrieved by other means: for example, the device could be equipped with a USB connection socket, or other connector, dedicated to the retrieval of the data from the log 60.

[0079] Reference will now be made to a charging station, in accordance with the invention and illustrated in [Fig.5], which comprises terminals 2 for charging vehicle batteries V.

[0080] Each of the terminals 2 incorporates a device 1 in accordance with the invention.

[0081] The charging station is a station located, for example, in a closed parking lot. It comprises walls 40 which have openings 41 for access to the charging terminals 2.

[0082] In the context of the example shown, each opening 41 is equipped with a movable wall, such as a fire-resistant curtain 42.

[0083] It should be understood that this is only a non-limiting example of implementation: the opening 41 could be hidden by a fixed wall, without departing from the scope of the invention.

[0084] When the opening is covered by a fixed fire-resistant wall, it has the same characteristics as fire curtains.

[0085] When the opening is concealed by a fire curtain 42, mounted to move between an open and closed position, the closing is either self-controlled using a thermal fuse, or remotely controlled by a fire safety system.

[0086] Self-controlled closing can be done by a thermal fuse made of eutectic alloy calibrated to a given temperature, thus releasing the curtain to obtain its complete closure, or by a thermoelectric fuse, calibrated to a given temperature, acting directly on the device held in the open position if it is of the electromagnetic type, thus releasing the moving part of the curtain to to obtain its complete closure.

[0087] The fuse trigger temperature can be any temperature between 60° and 230°C. This range is determined, on the one hand, when an ambient temperature inside a covered parking lot is higher than 60°C, which represents an abnormal and uncomfortable situation for the user. On the other hand, many materials have a self-ignition temperature between 300°C and 600°C, while paper has a self-ignition temperature around 230°C.

[0088] Triggering from 70°C seems advisable.

[0089] There are also provided ramps comprising water projection nozzles 43. These ramps are connected to a Guillemin type connector so that firefighters can connect their fire hoses directly to the curtains to spray the fire curtains 42 with water.

[0090] From the complete closure of the curtains until the emergency services fill with water, the curtains 42 are flame- and smoke-tight for at least 1 / 2h00 (E30), then once supplied with water by the fire brigade, the fire curtains have a fire resistance of fire resistance level IhOO (EI260) at least.

[0091] The nozzles 43 are positioned in the upper and lower parts of the boxes 44. The nozzles 43 positioned in the upper parts of the boxes 44 are directed towards the masonry frame and the upper slab of the recharging area in order to cool the supporting structure to prevent the building from collapsing under the effect of the heat produced by the fire. The nozzles 43 positioned in the lower parts of the boxes 44 participate in the cooling of the fixed and curtain walls.

[0092] Other actuated fire safety devices could be provided in a station in accordance with the invention, without however being limiting to the invention.

[0093] The station is equipped with the remote safety device mentioned above, which communicates with the devices 1 in accordance with the invention, integrated into the charging terminals.

[0094] This remote safety device is illustrated schematically by a box and bears the reference 50 on [Fig.5], and it is part of the station's fire safety system.

[0095] The method according to the invention, implemented in the station illustrated in [Fig. 5] is now described:

[0096] We consider two motor vehicles V, each comprising an electric battery 3 requiring recharging.

[0097] The motor vehicles V are each parked in a dedicated location, and the batteries 3 of each of the vehicles V are connected to the charging stations 2 using the connection cables 4.

[0098] Once the batteries 3 are connected to terminals 2, the devices 1 of each of the terminals 2 measure, for example for a predetermined time and at regular time intervals, the electrical data (i.e. data relating to the electrical power transmitted via the cables 4, to the voltage and / or to the current intensity) which are detected by the measuring devices equipping the devices 1.

[0099] These measured electrical data are stored as they are received in the log 60 of the memory 6 of the device 1, and transmitted to an intelligent module 7 which compares these detected data with the theoretical data which should be observed during the recharging of the battery, as a function of time.

[0100] If the intelligent module 7 detects a deviation between the measured electrical data and the theoretical electrical data, as a function of the charging time, which is greater than a first predetermined value or less than a second predetermined value, then it informs the control module 8 of the device 1.

[0101] This first value may be, for example, 25% higher than the theoretical data which should be observed.

[0102] If the value of the electrical data is greater than 25% of the theoretical data, then a control signal S 1 for securing the vehicle is generated by the control module 8 and transmitted by the transmitter / receiver 9 of the device 1.

[0103] This signal SI is received by the remote device 50 (represented schematically by a box) for securing said vehicle, which then triggers the securing of the vehicle and the station at the charging terminal connected to the vehicle V concerned.

[0104] Concretely, and as illustrated in [Fig.5], the safety of vehicle V and the station is achieved by closing the fire curtains 42 (see arrows F) and spraying water through the nozzles 43 of the ramps equipping the fire curtain boxes.

[0105] The electrical data recorded in log 60 of memory 6 is then retrieved and analyzed to understand why the security system was triggered.

[0106] Data recovery from log 60 can be done via the Internet or Lora, or by connecting a data recovery device directly to device 1.

[0107] This data transmitted via Internet or LoRa networks can be sent to a remote server of a fire safety monitoring unit, which may subsequently intervene to secure the parking lot and supply water to the charging area, then reopen the fire-resistant curtains once the danger has passed.

[0108] Other scenarios for implementing the device according to the invention could be envisaged.

[0109] For example, according to another mode of implementation, the device 1 is associated with a vehicle battery which is not recharged: the vehicle is moving and the device 1 is not visible because it is in the vehicle.

[0110] Even when the battery 3 is not connected to a charging station 2, the fire prevention device 1 can detect abnormal electrical data at the terminals of the battery 3.

[0111] If the electrical data (i.e. its power, the voltage at the terminals for example) are higher or lower than a predetermined threshold, for example -5% in this example of implementation, then the device 1 can alert the driver of the vehicle, for example with an audible alarm and a warning light, of a dangerous situation.

[0112] Device 1 can even trigger, via the vehicle's electronic system, safety devices for the vehicle: This may be, for example, an electronic control unit of the vehicle, which, when triggered, leads in particular to reducing the speed of said vehicle until it stops.

[0113] It is understood from the preceding description how the invention makes it possible to warn of imminent danger and makes it possible to trigger preventive actions before a dangerous event occurs, such as the battery catching fire.

[0114] It should be understood that the invention is not limited to the sole presence of the elements presented above, and that the devices in accordance with the invention could include other modules and other functionalities without departing from the scope of the invention, for example, once the fire risk has been clearly identified, giving the order to disperse inside the battery a refrigerant gas which could be of the R410A type or others, suddenly lowering the internal temperature of the battery in order to delay the thermal runaway of the battery, or even to avoid its thermal ignition.

Claims

Claims

1. Fire safety device (1), for preventing a fire in an electric battery (3) of a vehicle (V), in particular a motor vehicle, said device being capable of being connected to an electric current supply terminal (2) by means of a cable (4), said electric current having electrical data (voltage, intensity, etc.), said safety device (1) comprising: - at least one connection connector (10, 11), capable of connecting the device (1) to the battery (3), to said terminal (2) or to said power supply cable (4), - a device for measuring said electrical data detected at the connection connector (10, 11), - an intelligent module (7) which compares the measured electrical data with theoretical electrical data, representative of a theoretical state of charge of said battery (3) as a function of the charging time, said theoretical data being recorded in a memory (6) included in said device (1), and - a control module (8) which communicates with said intelligent module (7) and is capable of receiving an alert signal from said intelligent module (7) if a difference is observed between the measured electrical data and the theoretical electrical data, as a function of the charging time, said difference being greater than a first predetermined value or less than a second predetermined value, said control module (8) being capable of delivering a control signal (SI) for securing the vehicle, - a transmitter / receiver (9), capable of transmitting said control signal for securing said vehicle to a remote device (50) for securing said vehicle.

2. Device (1) according to claim 1, characterized in that the first predetermined value is greater than 25% of the theoretical voltage or intensity of the charge of the battery (3) as a function of time and in that the second predetermined value is -5% of the theoretical voltage or intensity of the charge of the battery (3) as a function of time.

3. Device (1) according to claim 1 or 2, characterized in that said memory (6) of said device (1) comprises a log in which the data are recorded, preferably at regular intervals electrical measured as a function of time.

4. Device (1) according to claim 3, characterized in that said device (1) comprises a connector allowing said device (1) to be connected to an external device in order to collect said data recorded in said log.

5. Device (1) according to any one of the preceding claims, characterized in that said connection connector comprises a first cable (4) to be connected to said terminal (2) and a second cable (4) to be connected to said battery (3).

6. Device (1) according to any one of claims 1 to 5, characterized in that said connection connector comprises a first socket which connects to said terminal (2) or to said battery (3), and a second socket to which said cable (4) is connected.

7. Battery (3) for a vehicle, in particular an automobile, associated with a device (1) according to any one of the preceding claims.

8. Charging terminal (2) associated with a device (1) according to any one of claims 1 to 6.

9. Installation comprising a vehicle battery (3), in particular an automobile, a terminal (2) for recharging said battery (3), a cable (4) for connecting said terminal (2) to said battery (3) and a device (1) according to any one of claims 1 to 6.

10. Charging station for a battery (3) of a vehicle, in particular a motor vehicle, comprising at least one installation according to claim 9 and a remote safety device.

11. Method for preventing a fire in an electric battery (3) of a vehicle, in particular a motor vehicle, using a device (1) according to any one of claims 1 to 5, said method comprising the following steps: - measurement of said electrical data detected at the connection connector of said device (1), - comparison of the measured electrical data with theoretical electrical data, by said intelligent module (7), and - transmission to the control module of an alert signal if the intelligent module (7) notes a difference between the measured electrical data and the theoretical electrical data, as a function of the charging time, said difference being greater than a first predetermined value or less than a second predetermined value, - delivery, by said control module, of a control signal vehicle safety, - reception of said control signal by a remote safety device of said vehicle and triggering of the safety device.

12. Method according to claim 11, implementing a fire safety device (1) associated with a battery (3), characterized in that the safety device is an electronic control unit of the vehicle, and in that the triggering of the safety device leads in particular to reducing the speed of said vehicle until it stops.

13. Method according to claim 11, implemented in an installation according to claim 9, characterized in that said remote device for securing said vehicle comprises at least one fire- and smoke-tight closing curtain of an entrance to said station, said curtain being mounted to move between an open position and a closed position, and in that the triggering of the safety device causes the curtain to move from the open position to the closed position of said entrance.

14. Method according to any one of claims 11 to 13, characterized in that it comprises an additional step of recording the measured electrical data in the memory (6) of said device (1).

15. Method according to any one of claims 11 to 14, characterized in that it comprises a step following which the measured electrical data are transmitted to a remote server of a fire safety monitoring unit.

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