CN106530582A - Electrical fire monitoring device, system and method - Google Patents

Abstract

The invention provides an electrical fire monitoring device, system and method, and relates to the technical field of safe electricity use. The electrical fire monitoring device includes a controller, a monitoring detector connected to the controller, a circuit breaker, an alarm, a communication module, and a memory and external sensors. The controller is used to receive the residual current transmitted by the monitoring detector; when the residual current is greater than the preset threshold, the alarm is triggered to give an alarm prompt or the circuit breaker is controlled to cut off the power supply of the main circuit; the controller is also used to judge the environmental parameters monitored by the external sensor Whether it is abnormal, if so, trigger the alarm to give an alarm prompt, and transmit the environmental parameters to the server. The electrical fire monitoring device, system and method provided by the present invention monitor the residual current of the power distribution circuit and collect the environmental parameters of the environment in which it is located. The monitoring can effectively avoid electrical fire accidents caused by environmental factors.

Description

Electrical fire monitoring device, system and method

technical field

The invention relates to the technical field of safe electricity utilization, in particular to an electrical fire monitoring device, system and method.

Background technique

With the continuous expansion of the low-voltage power distribution field and the continuous improvement of people's safety awareness, the protection of electrical fires has also received more and more attention. In order to limit the trend of electrical fires increasing year by year, more and more places, especially large shopping malls and entertainment The site chooses to use electrical fire monitoring devices for monitoring. Most of the monitoring in the prior art is based on the monitoring of power distribution rooms and distribution lines. Although accidents are avoided to a certain extent, most line fire accidents are often caused by Electrical circuit short circuit or combustible material burning and other environmental factors, for these accidents, the monitoring system in the prior art can rarely provide timely monitoring and alarm prompts, resulting in untimely detection by monitoring personnel, or difficulty in troubleshooting, which in turn caused Economic loss, also can't meet the prevention demand of electric fire.

Aiming at the above-mentioned problems of economic losses caused by the monitoring system not being able to detect accidents in time and not being easy to troubleshoot fault points, and not meeting the needs of electrical fire prevention, no effective solution has been proposed yet.

Contents of the invention

In view of this, the purpose of the present invention is to provide an electrical fire monitoring device, system and method to monitor the power distribution room and distribution lines, reduce the economic loss caused by electrical fire accidents, and meet the electrical fire prevention requirements.

In the first aspect, an embodiment of the present invention provides an electrical fire monitoring device, including: a controller and a monitoring detector connected to the controller, a circuit breaker, an alarm, a communication module, a memory, and an external sensor; the monitoring detector is set on The main switch in the distribution box includes residual current transformers and/or residual current detectors, which are used to monitor the residual current of each distribution circuit in the distribution box in real time and transmit the residual current to the controller; among them, the monitoring The detector also includes a current terminal connected to the power lines of each power distribution circuit; the controller is arranged in the distribution box to receive the residual current transmitted by the monitoring detector; when the residual current is greater than the preset first threshold, trigger the The alarm prompts the alarm, and sends the line of the alarm prompt and the identification information of the monitoring detector to the server through the communication module; when the residual current is greater than the second threshold, the control circuit breaker cuts off the power supply of the main circuit; wherein, the second threshold is greater than The first threshold, the identification information of the monitoring detector includes the ID number of the monitoring detector and the installation location information of the monitoring detector; the identification information is pre-stored in the memory; the above-mentioned communication module includes a wireless communication unit, and the controller communicates with the server through the communication module Wireless communication; the above-mentioned external sensor is set outside the power distribution box, and includes at least one independent sensing probe for collecting environmental parameters of the environment; the external sensor also includes a data transceiver, which is connected to the sensing probe for It is used to receive the environmental parameters collected by the sensing probe, and transmit the environmental parameters to the controller, wherein the external sensors include temperature sensors, humidity sensors and smoke sensors; the above-mentioned controller is also used to determine whether the environment where the external sensors are located is Abnormal, if abnormal, trigger the alarm to give an alarm prompt, and transmit the environmental parameters to the server in real time.

With reference to the first aspect, the embodiment of the present invention provides a first possible implementation manner of the first aspect, wherein the above-mentioned alarm is an audible and visual alarm, configured to send out an audible and visual alarm signal under the trigger of the controller.

With reference to the first aspect, the embodiment of the present invention provides a second possible implementation manner of the first aspect, wherein the above-mentioned device further includes a power supply module, configured to supply power to the device.

In combination with the first aspect, the embodiment of the present invention provides a third possible implementation of the first aspect, wherein the above-mentioned controller, monitoring detector, circuit breaker, communication module and memory are packaged in a box; the box is set There are box doors and box locks.

In combination with the first aspect, the embodiment of the present invention provides a fourth possible implementation manner of the first aspect, wherein the above-mentioned device further includes a network sharing module connected to the controller, and the network sharing module includes a Bluetooth connection unit and/or a wifi The unit is used to connect with the mobile terminal; the above-mentioned controller is also used to transmit the environmental parameters to the mobile terminal through the network sharing module.

In a second aspect, an embodiment of the present invention further provides an electrical fire monitoring system, which includes a plurality of electrical fire monitoring devices described in the first aspect above, and also includes a server; the server communicates wirelessly with the electrical fire monitoring device.

In combination with the second aspect, the embodiment of the present invention provides a first possible implementation of the second aspect, wherein the above system further includes a host computer installed on the side of the server; the host computer is installed in the power distribution monitoring room for Display the monitoring status of the system to the monitoring personnel.

In combination with the second aspect, the embodiment of the present invention provides a second possible implementation of the second aspect, wherein the above-mentioned system further includes an automatic alarm system; when the server receives the alarm information from the electrical fire monitoring device, it triggers an automatic alarm system. The alarm system gives an alarm.

In the third aspect, the embodiment of the present invention also provides an electrical fire monitoring method, which is implemented by the electrical fire monitoring device described in the first aspect, including: the controller monitors the residual current of the power distribution circuit in real time through the monitoring detector; The device monitors the environmental parameters of the environment where the external sensor is located in real time through the external sensor; the external sensor includes: a temperature sensor, a humidity sensor and a smoke sensor; when the residual current is greater than the preset first threshold, the alarm is triggered to give an alarm prompt, And send the warning line and the identification information of the monitoring detector to the server through the communication module; when the residual current is greater than the second threshold, the control circuit breaker cuts off the power supply of the main circuit; wherein, the second threshold is greater than the first threshold, and the monitoring and detection The identification information of the sensor includes the ID number of the monitoring detector and the installation location information of the monitoring detector; the above identification information is pre-stored in the memory; when the environmental parameters determine that there is abnormal information in the environment where the external sensor is located, the alarm will be triggered to give an alarm prompt , and transmit the environment parameters to the server.

In combination with the third aspect, the embodiment of the present invention provides a first possible implementation manner of the third aspect, wherein the above-mentioned environmental parameters determine that the abnormal information in the environment where the external sensor is located includes at least one of the following: the temperature detected by the temperature sensor The parameter is higher than the preset temperature threshold; the humidity parameter detected by the humidity sensor is higher than the preset humidity threshold; the smoke concentration parameter detected by the smoke sensor is higher than the preset smoke concentration threshold.

Embodiments of the present invention bring the following beneficial effects:

An electrical fire monitoring device, system and method provided by the embodiments of the present invention monitor the residual current of each power distribution circuit in real time through monitoring detectors, and collect environmental parameters of the environment in real time through external sensors. At the same time as the monitoring of distribution lines, it can also monitor the external environment, effectively avoiding accidents caused by factors such as short circuit or combustible combustion of electrical lines. Send it to the monitoring personnel, which will help the monitoring personnel improve the efficiency of investigation.

Furthermore, the electrical fire monitoring system provided by the embodiment of the present invention also includes an automatic alarm system, which can give an alarm prompt in time when a fire accident occurs, which helps to reduce economic losses and further meets the prevention needs of electrical fires.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

In order to make the above-mentioned objects, features and advantages of the present invention more comprehensible, preferred embodiments will be described in detail below together with the accompanying drawings.

Description of drawings

In order to more clearly illustrate the specific implementation of the present invention or the technical solutions in the prior art, the following will briefly introduce the accompanying drawings that need to be used in the specific implementation or description of the prior art. Obviously, the accompanying drawings in the following description The drawings show some implementations of the present invention. For those skilled in the art, other drawings can also be obtained according to these drawings without creative work.

Fig. 1 is a schematic diagram of the internal control structure of an electrical fire monitoring device provided by an embodiment of the present invention;

2 is a schematic diagram of a specific internal control structure of an electrical fire monitoring device provided by an embodiment of the present invention;

Fig. 3 is a structural block diagram of an electrical fire monitoring system provided by an embodiment of the present invention;

Fig. 4 is a flowchart of an electrical fire monitoring method provided by an embodiment of the present invention.

detailed description

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. the embodiment. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts belong to the protection scope of the present invention.

Considering that the monitoring system in the prior art is mostly based on the monitoring of power distribution rooms and distribution lines, but lacks environmental monitoring, resulting in the problem of electrical line failures caused by environmental factors, which in turn cause economic losses, the embodiment of the present invention provides a An electrical fire monitoring device, system and method are provided to meet the needs of electrical fire prevention.

In order to facilitate the understanding of this embodiment, an electrical fire monitoring device disclosed in the embodiment of the present invention is firstly introduced in detail,

Embodiment one:

Figure 1 shows a schematic diagram of the internal control structure of an electrical fire monitoring device provided by an embodiment of the present invention, which includes: a controller 100 and a monitoring detector 101 connected to the controller 100, a circuit breaker 102, and an alarm 103 , a communication module 104, a memory 105 and an external sensor 106; the monitoring detector 101 is set at the main switch in the distribution box, including a residual current transformer and/or a residual current detector for real-time monitoring of each distribution box in the distribution box The residual current of the electrical circuit, and transmit the residual current to the controller 100; wherein, the monitoring detector 101 also includes a current terminal (not shown in FIG. 1 ) connected to the power line of each power distribution circuit; the controller 100 is set in the distribution Inside the electric box, it is used to receive the residual current transmitted by the monitoring detector 101.

When the residual current is greater than the preset first threshold, the alarm 103 is triggered to give an alarm prompt, and the line of the alarm prompt and the identification information of the monitoring detector 101 are sent to the server through the communication module 104; when the residual current is greater than the second threshold , control the circuit breaker 102 to cut off the power supply of the main circuit; wherein, the second threshold is greater than the first threshold, and the identification information of the monitoring detector 101 includes the ID number of the monitoring detector 101 and the installation location information of the monitoring detector 101; stored in memory 105. The communication module 104 includes a wireless communication unit (not shown in FIG. 1 ), and the controller 100 communicates wirelessly with the server through the communication module 104 .

Above-mentioned external sensor 106 is arranged on the outside of distribution box, and comprises at least one independent sensing probe (not shown in Fig. 1), is used for collecting the environment parameter of environment; External sensor also comprises data transceiver (Fig. 1 not shown in ), the data transceiver is connected with the sensing probe for receiving the environmental parameters collected by the sensing probe and transmitting the environmental parameters to the controller 100, wherein the external sensors include a temperature sensor, a humidity sensor and a smoke sensor The controller 100 is also used to determine whether the environment of the external sensor 106 is abnormal according to the above environmental parameters, if abnormal, trigger the alarm 103 to give an alarm prompt, and transmit the environmental parameters to the server in real time.

An electrical fire monitoring device provided by an embodiment of the present invention monitors the residual current of each power distribution circuit in real time through monitoring detectors, and collects environmental parameters of the environment in real time through external sensors. While monitoring the external environment, it can effectively avoid accidents caused by short circuit of electrical lines or combustion of combustibles.

During specific implementation, the above-mentioned device can be installed in large-scale places, such as in the main distribution box of shopping malls, theaters, cinemas and gymnasiums, etc., and the number of sensing probes included in the above-mentioned external sensor 106 can be multiple, and installed in densely populated places , and important lines, including fire protection, security, emergency power supply, channel lighting lines, and important places that do not allow power outages, in order to monitor the external environment, which not only ensures the safety of electricity use, but also ensures the uninterrupted use of electricity.

In actual application, the above-mentioned alarm is an audible and visual alarm, which is used to send out an audible and visual alarm signal under the trigger of the controller 100 . Figure 2 shows a schematic diagram of a specific internal control structure of the electrical fire monitoring device provided by the above-mentioned embodiment, in addition to the structure shown in Figure 1, it also includes a power supply module 107, a network sharing unit 108, a wireless communication unit 201 and a sensor probe 202. Wherein, the power supply module 107 is used to provide power supply for the above-mentioned devices. The network sharing module 108 is connected with the controller 100, including a bluetooth connection unit 108a and/or a wifi unit 108b for connecting with a mobile terminal; the controller 100 is also used to transmit the environmental parameters to the mobile terminal through the network sharing module 108, specifically When implemented, the above-mentioned device can be connected to the mobile terminal of the power supervisor through the network sharing module 108, for example, the mobile phone of the power supervisor can be connected through the wifi network, and the monitoring information can be sent to the supervisor in time, which helps the supervisor to improve the efficiency of investigation .

Specifically, the above-mentioned controller 100, monitoring detector 101, circuit breaker 102, communication module 104 and memory 105 can be packaged in a box, the box is set in the distribution box, and the box is provided with a box door and box Lock to prevent other people from opening it by mistake, further improving the protection of electricity safety.

Embodiment two:

In order to facilitate a further understanding of the electrical fire monitoring device provided in the above embodiments, on the basis of the above embodiments, an embodiment of the present invention also provides an electrical fire monitoring system, which includes the electrical fire monitoring device described in the above embodiments , also includes a server, and the server communicates wirelessly with the electrical fire monitoring device.

FIG. 3 shows a structural block diagram of an electrical fire monitoring system provided by an embodiment of the present invention, including a server 300 , multiple electrical fire monitoring devices 302 and a host computer 303 . The server 300 communicates wirelessly with the electrical fire monitoring device through a wireless network; the server 300 is used to receive the data sent by the electrical fire monitoring device; analyze and process the data, and store it in the database. In a specific implementation, the above system also includes a host computer 303 installed on the side of the server 300; the host computer 303 is installed in the power distribution monitoring room, and is used to display the monitoring status of the system to the monitoring personnel. It should be understood that, in other embodiments, the number of the above-mentioned electrical fire monitoring devices may also be other values, which may be set according to actual conditions in actual use, which is not limited in this embodiment.

In actual application, the above system also includes an automatic alarm system; when the server 300 receives the alarm information from the electrical fire monitoring device 302, the automatic alarm system is triggered to give an alarm. For example, when the sensor probe detects the abnormal information that the smoke concentration in a certain place is greater than the preset value, after reporting the abnormal information to the server, it can also automatically send a fire alarm to the security personnel or firefighters under the settings of the power monitoring personnel. Alarm prompts to prevent accidents from expanding and causing unnecessary economic losses.

The electrical fire monitoring system provided by the embodiment of the present invention can send the monitoring information of the electrical fire monitoring device to the server by communicating the electrical fire monitoring device with the server, so as to realize the monitoring of the power distribution room and the power distribution line, and at the same time The external environment is monitored in real time, and when abnormal information occurs, an alarm can be issued in time, which helps to reduce economic losses and further meets the needs of electrical fire prevention.

The electrical fire monitoring system provided by the embodiment of the present invention has the same technical features as the electrical fire monitoring device provided by the above embodiment, so it can also solve the same technical problem and achieve the same technical effect.

Embodiment three:

Corresponding to the electrical fire monitoring device provided in the first embodiment above, the embodiment of the present invention also provides an electrical fire monitoring method, which is realized by the above electrical fire monitoring device, as shown in Figure 4, the flow of an electrical fire monitoring method described above Figure, the method includes the following steps:

Step S402, the controller monitors the residual current of the power distribution circuit in real time through the monitoring detector;

Step S404, the controller monitors the environmental parameters of the environment where the external sensor is located in real time through the external sensor;

Wherein, the above-mentioned external sensors include: temperature sensor, humidity sensor and smoke sensor; in actual use, one or more sensing probes may be set at different positions of the monitored area to achieve the purpose of monitoring.

Step S406, when the residual current is greater than the preset first threshold, trigger the alarm to give an alarm prompt, and send the alarm prompt line and the identification information of the monitoring detector to the server through the communication module; when the residual current is greater than the second When the threshold is reached, the control circuit breaker cuts off the power supply of the main circuit;

Wherein, the above-mentioned second threshold is greater than the first threshold, and the identification information of the monitoring detector includes the ID number of the monitoring detector and the installation location information of the monitoring detector; and, the identification information is pre-stored in the memory.

Step S408, when the environment parameter determines that the environment of the external sensor has abnormal information, an alarm is triggered to give an alarm prompt, and the environment parameter is transmitted to the server.

During specific implementation, the above-mentioned environmental parameters and the abnormal information in the environment where the external sensor is located include at least one of the following: the temperature parameter detected by the temperature sensor is higher than the preset temperature threshold; the humidity parameter detected by the humidity sensor is higher than the preset humidity threshold The smoke concentration parameter detected by the smoke sensor is greater than the preset smoke concentration threshold. Further, the power supervision department can also set it on the server. When these abnormal phenomena occur, the control controller triggers the circuit breaker to cut off the power supply of the main circuit, so as to Avoid expanding economic losses. Through the monitoring of these parameters, electrical fire accidents caused by environmental factors such as electrical circuit short circuit or combustible combustion can be effectively avoided, and the prevention level of electrical fires has been improved.

An electrical fire monitoring method provided by the embodiment of the present invention monitors the residual current of each power distribution circuit in real time through the monitoring detector, and collects the environmental parameters of the environment in real time through the external sensor. At the same time, it realizes the monitoring of the external environment, effectively avoiding accidents caused by factors such as short circuit or combustible combustion of electrical lines, and further improving the level of prevention of electrical fires.

The computer program product of the electrical fire monitoring device, system and method provided by the embodiments of the present invention includes a computer-readable storage medium storing program codes, and the instructions included in the program codes can be used to execute the steps described in the previous embodiments For specific implementation, reference may be made to the embodiments, and details are not repeated here.

Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working process of the above-described system and device can refer to the corresponding process in the foregoing method embodiments, which will not be repeated here.

In addition, in the description of the embodiments of the present invention, unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection , or integrally connected; it may be mechanically connected or electrically connected; it may be directly connected or indirectly connected through an intermediary, and it may be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood in specific situations. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and should not be construed as indicating or implying relative importance.

If the functions described above are realized in the form of software function units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the essence of the technical solution of the present invention or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk, and other media that can store program codes.

Finally, it should be noted that: the above examples are only specific implementations of the present invention, to illustrate the technical solutions of the present invention, rather than to limit them, and the protection scope of the present invention is not limited thereto, although with reference to the foregoing examples The present invention has been described in detail, and those skilled in the art should understand that: within the technical scope disclosed by the present invention, any person skilled in the art can still modify the technical solutions described in the foregoing embodiments or can easily think of them Changes, or equivalent replacements for some of the technical features; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be covered by the protection scope of the present invention Inside. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (10)

1. a kind of electric fire monitoring device, it is characterised in that include：Controller and the monitoring detection being connected with the controller Device, breaker, alarm, communication module, memory and external sensor；

The monitoring detector is arranged at the main switch in distribution box, is visited including residual current transformer and/or residual current Device is surveyed, for the residual current of each distribution loop in monitor in real time distribution box, and the residual current is transmitted to controller； Wherein, the monitoring detector also includes the current terminal being connected with the power line of each distribution loop；

The controller is arranged in the distribution box, for receiving the residual current of the monitoring detector transmission；

When the residual current is more than the first threshold for pre-setting, triggering the alarm carries out alarm, and will report The alert circuit of prompting and the identification information of the monitoring detector are sent to server by the communication module；When described surplus When aftercurrent is more than Second Threshold, the power supply of the circuit breaker trip major loop is controlled；Wherein, the Second Threshold is more than described First threshold, the identification information of the monitoring detector include No. ID of the monitoring detector and the peace of the monitoring detector Holding position information；The identification information is prestored in which memory；

The communication module includes radio communication unit, and the controller carries out channel radio by the communication module and server News；

The external sensor is arranged on outside the distribution box, and including at least one independent sensing probe, for gathering The ambient parameter of place's environment；The external sensor also includes data collector, and the data collector is visited with the sensing Head connection, for receiving the ambient parameter of the sensing probe collection, and the ambient parameter is transmitted to the controller, its In, the external sensor includes temperature sensor, humidity sensor and Smoke Sensor；

Whether extremely the controller is additionally operable to the environment according to residing for the ambient parameter determines the external sensor, if Abnormal, triggering the alarm carries out alarm, and by the ambient parameter real-time Transmission to the server.

2. device according to claim 1, it is characterised in that the alarm is audible-visual annunciator, in the control The triggering of device processed issues visual alarm of speaking.

3. device according to claim 1, it is characterised in that described device also includes power module, for the dress Offer supply of electric power is provided.

4. device according to claim 1, it is characterised in that the controller, the monitoring detector, the open circuit Device, the communication module and the memory package are in a casing；

The casing is provided with chamber door and case lock.

5. device according to claim 1, it is characterised in that described device also includes the network being connected with the controller Sharing module, the network share module include bluetooth connection unit and/or wifi units, for being connected with mobile terminal；

The controller is additionally operable to the ambient parameter by the network share module transfer to the mobile terminal.

6. a kind of electric fire monitoring system, it is characterised in that the system includes the electricity described in any one of Claims 1 to 5 Gas fire-disaster monitoring device, also including server；

The server and the electric fire monitoring device wireless telecommunications.

7. system according to claim 6, it is characterised in that the system also includes being arranged on the server-side Host computer；The host computer is arranged on distribution monitor room, for the monitor state of the system is shown to monitoring personnel.

8. system according to claim 6, it is characterised in that the system also includes automatic alarm system；For working as When stating server and receiving the warning message of the electric fire monitoring device, trigger the automatic alarm system and reported to the police.

9. a kind of electric fire monitoring method, it is characterised in that methods described is by the electricity described in any one of Claims 1 to 5 The realization of gas fire-disaster monitoring device, including：

Residual current of the controller by monitoring detector monitor in real time distribution loop；

Ambient parameter of the controller by the environment described in external sensor monitor in real time residing for external sensor；Wherein, The external sensor includes：Temperature sensor, humidity sensor and Smoke Sensor；

When the residual current is more than the first threshold for pre-setting, triggering alarm carries out alarm, and warning is carried The circuit for showing and the identification information of the monitoring detector are sent to server by communication module；When the residual current it is big When Second Threshold, the power supply of circuit breaker trip major loop is controlled；Wherein, the Second Threshold is more than the first threshold, institute The identification information for stating monitoring detector includes No. ID of the monitoring detector and the installation site information of the monitoring detector； The identification information is prestored in memory；

When abnormal information occurs in the environment residing for the ambient parameter determines the external sensor, trigger the alarm and enter Row alarm, and the ambient parameter is transmitted to the server.

10. method according to claim 9, it is characterised in that the ambient parameter is determined residing for the external sensor Environment occur abnormal information at least include one below：

The temperature parameter of the temperature sensor detection is higher than the temperature threshold for pre-setting；

The humidity parameter of the humidity sensor detection is more than the humidity threshold for pre-setting；

The smokescope parameter of the Smoke Sensor detection is more than the smoke density threshold value for pre-setting.