JPH08255291A - Method for correcting smoke sensor - Google Patents

Abstract

PURPOSE: To surely correct the zero point, a test warning point and changing expression of a smoke sensor without increasing an uncautioned state. CONSTITUTION: The difference d of the zero point value Z1 of the smoke sensor till a present time for correcting the zero point and the test warning point of the smoke sensor which detects fire or a smoke density in a monitoring area by the change of light receiving quantity with fire smoke are corrected with the newly measured zero point value Z2 is obtained. When the difference d is within correcting limit width L, the zero point value Z1 is corrected to be the newly obtained value Z2 and, moreover, a test warning point value F1 is corrected to be the value F2 obtained by correction for the portion of difference d. Then, the changing expression of the light receiving quantity and the smoke density is calculated and corrected by the corrected zero point value and the test warning point value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a zero point, a warning point, and a conversion characteristic connecting the zero point and the warning point of a smoke detector for detecting the smoke density or the fire in the monitoring area by the change in the amount of light received with the smoke of the fire. The present invention relates to a smoke sensor correction method for performing (conversion) correction.

[0002]

2. Description of the Related Art Conventionally, in a fire alarm system, a sensor is regularly inspected to check whether the sensor is normal or not. For example, in a fire alarm system using an analog photoelectric smoke detector, the receiver or the analog smoke detector itself has a conversion formula table that converts the amount of light received by the sensor unit of the analog smoke detector into smoke concentration. The current smoke density is measured using this conversion formula.

However, the smoke detector in the analog smoke detector,
When the detection element becomes dirty with dust or changes over time, the amount of received light changes, and the zero point (the amount of received light in a steady state without smoke) and the alarm point (the amount of received light that is determined to be a fire) ) Also changes. Of course, the conversion formula also changes due to changes in the zero point and the reporting point. Therefore, the smoke density cannot be accurately measured based on the amount of light received by the analog smoke sensor, which leads to the occurrence of false alarms.

For this reason, it is necessary to check the zero point periodically (every day or every week) and the amount of light received (test reporting point) when the testing LED is turned on to artificially make a fire. Then, a conversion formula for the analog smoke detector was newly created from these two points to prevent erroneous detection of smoke density.

[0005]

It is necessary to carry out such an inspection in order to prevent a false alarm from being given to the analog smoke detector, and it is desirable that an accurate conversion formula is constantly sought. However, if the inspection period is shortened for that purpose, the test L
Since the ED is turned on, the period in which the ED is not alerted increases. Furthermore, since the test LED is turned on, much power is consumed.

On the contrary, if the inspection period is lengthened, it may be delayed in detecting a failure of the analog smoke sensor, or the period not converted by an accurate conversion formula may be increased. Further, when measuring the zero point at the time of inspection, if dust or smoke is temporarily present, the value may be set to the zero point.

The present invention has been made based on such a background, and an object thereof is to correct to a more accurate zero point, a test reporting point and a conversion formula without increasing the number of unwarned states. It is to provide a method of correcting a smoke sensor.

[0008]

In order to achieve this object, the present invention is directed to the smoke density of a monitoring area or the smoke density of a smoke detector for detecting a fire based on a change in the quantity of light received with the smoke of a fire. In a smoke sensor correction method for correcting conversion characteristics between two, a first difference value between a zero value of the smoke sensor up to the present time and a newly measured zero value (a zero value obtained by averaging a large number of measured values) is calculated. Process, and if the difference is within the correction limit width, the second process of correcting the zero point value to the newly obtained value, and the third process of setting the test reporting point value to the value corrected by the difference. And the fourth step of correcting the conversion characteristic to a conversion characteristic obtained by connecting the corrected zero point value and the test reporting point value.

In this case, if the difference exceeds the correction limit width, the zero point value and the test alarm point value are corrected to the current value plus the correction limit width. Further, in this case, the test report may be issued by the test command at an interval longer than the zero point correction to obtain an accurate test report point.

[0010]

In the present invention, only the zero point that does not affect fire monitoring is measured in a short-term cycle, for example, every hour, and the zero point is corrected. Then, the difference between the zero points before and after the measurement is obtained, and the test reporting point is also corrected in a pseudo manner by the difference. Then, finally, the conversion characteristic (conversion formula) connecting the zero point and the test reporting point is corrected to a conversion formula based on the corrected zero point and the test reporting point.

Further, the accurate measurement of the test reporting point is performed during the period (one day or one week) which does not affect the conventional detection, and the test reporting point and the conversion formula are accurately corrected at that time. . When correcting the zero point, the latest analog value at the time of correction may be taken, but the more accurate zero point can be corrected by taking the average of a large number of analog values.
Furthermore, a correction limit width (range) is set for the correction of the zero point, and if the correction value of the zero point exceeds the correction limit width so that the value of the zero point does not change suddenly, Instead of correcting as it is, it is corrected by the correction limit width.

[0012]

FIG. 1 is a block diagram showing a first embodiment of a disaster prevention monitoring device according to the present invention. In FIG. 1, a plurality of transmission lines 8 are drawn from the receiver 1, and an analog heat detector 2, an analog smoke detector 3, a detector repeater 4, and a control relay are provided as terminals on the transmission lines 8 of each system. The repeater 5 is connected. Further, a sensor line 9 is drawn from the sensor repeater 4, a plurality of on / off sensors 6 are connected, and a termination resistance 6a for disconnection monitoring is connected to the end. further,
A control device 7 such as a smoke control device is connected to the line drawn from the control repeater 5.

A maximum of 127 terminals can be connected to the transmission path 8 of one system, and a maximum of 127 types of unique addresses and type information are preset in each terminal. Further, a maximum of 4 lines are drawn from the sensor repeater 4 and the control repeater 5. The receiver 1 includes a main MPU 11 that manages the entire receiver, for example, two sub MPUs 12-1 and 12-2 that perform data transmission with a terminal, an operation unit 13, a display unit 14, and a power supply unit 15. It is provided.

The main MPU 11 has a reception controller 16. In addition to the fire reception process, the reception control unit 16 sets the sub-MPU 12 at a predetermined zero point correction cycle, for example, once an hour.
Issue a zero point correction request command to -1, 12-2, and a predetermined test reporting point correction cycle, for example, once a day, sub-M
A conversion-type correction request command is issued to the PUs 12-1 and 12-2.

Each of the sub MPUs 12-1 and 12-2 is
Transmission control unit 17, correction processing unit 18, and fire determination unit 19
Have. In the normal monitoring state, the transmission control unit 17 repeats the process of sequentially sending the polling commands to collect the information of each terminal and sending the AD conversion command every one second, for example. The AD conversion command is a common command that does not depend on the addresses of the analog heat sensor 2 and the analog smoke sensor 3, and when the terminal receives the AD conversion command, the analog detection data of the currently detected heat or smoke is AD converted. And hold it in memory.
The data held in the memory is sent to the receiver when the self-address included in the polling command following the AD conversion command is determined.

Furthermore, each of the sub-MPUs 12-1 and 12-2 can issue a test command to perform an operation test of the analog heat detector 2 and the analog smoke detector 3.
The analog smoke detector 3 to which the present invention is directed is provided with a scattered light type smoke detector, and the light receiving element detects the amount of scattered light according to the concentration of smoke. A test LED for a test is provided at a position facing the light receiving element of the smoke detector, and when the test command is received, the test LED is turned on and a smoke concentration of, for example, 18 [% / m], which is a test reporting point, is emitted. The light receiving element is irradiated with the amount of scattered light corresponding to. This test reporting point is set to the upper limit of the convertible range when the sensor converts the received light amount into smoke density using the conversion formula Y = aX + b. This is the lower limit of the convertible range. This is because a more accurate conversion formula can be obtained by measuring two points apart from the zero point and the test reporting point of the upper limit value.

The fire judging section 19 of each of the sub MPUs 12-1 and 12-2 uses the detection data X from the analog smoke sensor 3 collected by the transmission control section 17 as Y = aX + which is predetermined.
The smoke density Y is converted according to the conversion formula of b, and when the smoke density at the alarm point set in advance is exceeded, the main MPU 11 is notified of the occurrence of a fire and the reception control unit 16 performs the fire reception process.

The fire determination unit 19 holds constants a and b used in the conversion formula Y = aX + b in a memory, and the constants a and b are retained.
Is obtained from the measurement result of the zero-point measurement at the time of initialization diagnosis processing accompanying power-on and the measurement of the test reporting point by lighting the test LED. The correction processing unit 18 has a zero-point correction function, and each time it receives a zero-point correction request command from the main MPU 11, for example, once every hour, the analog smoke sensor 3
The correction process of the fire determination unit 19 is performed based on the measurement of the zero point. When the conversion type correction request command is received once a day from the main MPU 11, the analog smoke detector 3
Fire Judgment Unit 19 Based on Measurement of Zero Point and Test Warning Point
Correction processing is performed.

FIG. 2 is a block diagram on the terminal side of the second embodiment of the disaster prevention monitoring apparatus according to the present invention. In this second embodiment,
The analog smoke detector 3 on the terminal side is provided with a conversion function of Y = aX + b of the fire determination unit 19 included in the sub MPUs 12-1 and 12-2 of the receiver 1 of FIG. That is, the sensor unit 21, the transmission control unit 22, the correction processing unit 23, and the conversion unit 24 are provided. A conversion formula Y = aX + b is set in the conversion unit 24, and the analog detection signal X from the sensor unit 21 is AD-converted and then converted into smoke density Y according to the conversion formula.

Therefore, for polling from the receiver,
The transmission control unit 22 responds with the smoke density data Y converted by the conversion unit 24. Since the analog smoke sensor 3 includes the conversion unit 24 as described above, the correction processing unit 23 is provided to correct the conversion formula. The correction processor 23 receives the zero-point correction request command and the conversion-type correction request command from the receiver 1 except that the sub-MP of FIG.
This is the same as the correction processing unit 18 provided in U12-1, 12-2.

FIG. 3 is a block diagram on the terminal side of the third embodiment of the disaster prevention monitoring apparatus according to the present invention.
The addressable smoke sensor has a correction processing function. The addressable smoke detector is shown in FIG.
In addition to the embodiment, a fire judging unit 25 is further provided. That is, it is a smoke detector in which the smoke detector itself has a fire determination function. The detection data X from the sensor unit 21 is converted into the conversion unit 2
In step 4, the smoke density data Y is converted and input to the fire determination unit 25. The fire determination unit 25 compares the smoke density data with the smoke density at the reporting point, returns data of "0" if it is less than the smoke density at the reporting point, and returns "0" if it is more than the smoke density at the reporting point. The data of "1" is transmitted to the receiver 1 as a fire determination result.

The smoke detector is also capable of returning the smoke density data Y converted by the conversion formula by a dedicated command from the receiver. Also in this case, the correction processing unit 23 performs the correction processing based on the zero-point correction request command and the conversion-type correction request command transmitted from the receiver 1.
On the other hand, the present invention is also applicable to a system in which the smoke sensor does not have the conversion unit 24 but includes the sensor unit 21, the fire determination unit 25, and the transmission control unit 22 and the conversion unit is provided in the sub MPU of the receiver 1. Applicable. In other words, this smoke detector is
Directly input the detection data X from the fire determination unit 25,
The fire determination unit 25 is a smoke detector that compares the detected data with a preset alarm point value, and if the alarm point value is greater than or equal to the alarm point value, transmits data of "1" to the receiver 1 as a fire determination result. Furthermore, the detection data X can be returned by a dedicated command from the receiver 1.

The detection data returned by the dedicated command can be converted into a smoke density value by the conversion formula of the receiver 1 and monitored. In this case, the sub MPU is provided with a correction processing unit, and when a zero point correction request command or a conversion type correction request command is received from the main MPU 11, the sub MPU
Sends a dedicated command to the smoke sensor to have it send back the detection data of the smoke sensor, and from this detection data, performs a variable-type correction process of the conversion unit. In this smoke detector correction process, the smoke density value at the reporting point of the fire determination unit 25 must also be corrected. Therefore, a new alerting point value is calculated from the corrected conversion formula and is sent to the smoke detector for correction.

Further, as another embodiment of the present invention, the same can be applied to the fire alarm equipment having the sub-MPUs 12-1 and 12-2 of FIG. 1 in the relay board, and the command from the receiver or the relay board itself. The correction process may be performed by. Next, the zero point correction processing of the present invention will be described by taking the embodiment of FIG. 1 as an example. FIG. 4 is a flowchart of the zero point correction control in the main MPU 11 of the receiver 1. First, a state monitoring process is performed in step S1. Next, in step S2, it is determined whether or not the zero point correction period has been reached. Here, the zero point correction cycle is set to, for example, 1 hour. If it is the zero point correction cycle, it is determined in step S3 whether the conversion type correction cycle has been reached. Here, the conversion type correction cycle is, for example, one day (2
4 hours).

If it is not a conversion type correction cycle, the process proceeds to step S4, and a zero point correction request command is transmitted to the sub MPUs 12-1 and 12-2. If it is a conversion type correction cycle, step S
In step 5, the conversion type correction request command is transmitted to the sub MPUs 12-1 and 12-2. Step S6 is another receiver process, and this process includes the display unit 14 associated with the fire detection.
The alarm display process for the, and various processes associated with the operation input from the operation unit 13 are included.

FIG. 5 shows the sub-MPU 12-1, 1 of the receiver 1.
2 is a flowchart of a zero point correction process in 2-2,
It is executed when a zero point correction request command is received from the main MPU 11. First, in step S11, the absolute value of the difference d = Z2-Z1 between the current zero point value Z1 and the newly measured zero point value Z2 (hereinafter referred to as "measured zero point value Z2") is larger than the correction limit width L. Determine whether

The measurement zero point value Z2 may be measured as follows. In the steady monitoring state, the sub MPU 12
Each of -1, 12-2 collects the detection data of the analog smoke sensor 3 by transmitting the polling command, and the collected detection data for the past 10 minutes is held in the memory. Therefore, when the correction request command is received, a plurality of latest data are read out from the collected data held in the memory and the measured zero point value Z2 is obtained as an average value thereof.
Ask for. Further, the measurement value Z2 may be obtained as an average value of a plurality of detection data collected after receiving the correction request command.

If the absolute value of the difference d does not exceed the correction limit width L in step S11, the difference d is calculated in step S12.
Is a correction value h. Also, the absolute value of the difference d is the correction limit width L
If it exceeds, the correction limit width L is set to the correction value h in step S13. Next, in step S14, the magnitude of the zero point value Z1 and the measured zero point value Z2 are compared. If the measured zero point value Z2 is larger than the current zero point value Z1, step S15.
Then, the zero point value Z1 is corrected upward by the difference d or the correction value h of the correction limit width L.

That is, (Z1 + h) is set as a new zero point value. Here, the corrected zero point value is set to Z2 '. At the same time, the test reporting point value F1 is also artificially corrected upward by the correction value h. That is, (F1 + h) is set as a new test reporting point value.
Here, the corrected test reporting point value is set to F2. On the other hand, when the current zero point value Z1 is larger than the measured zero point value Z2, the zero point value Z1 is similarly corrected downward by the difference d or the correction value h of the correction limit width L in step S16. That is, (Z1-h) is set as a new zero point value. Here, the corrected zero point value is set to Z2 '. At the same time the test reporting point value F
1 is also corrected downward by the correction value h, and the test reporting point value F2
And That is, (F1-h) is set to the new test reporting point value F
Set to 2.

Next, in step S17, it is determined whether the corrected zero point value Z2 'and the test alarm point value F2 are within a predetermined specified level range. If it is not within the range of the specified level, it means that a fault has occurred in the analog smoke sensor 3, so that the terminal fault occurrence process is performed in step S18 and an abnormal alarm is issued. When the zero point value Z2 'and the test reporting point value F2 are within the specified level range,
Next, in step S19, a conversion formula is calculated and corrected from the corrected zero point value Z2 'and the test reporting point value F2.

FIG. 6 is a flow chart of the correction processing in the sub MPUs 12-1 and 12-2 which is executed when the conversion type correction request command is received. First, step S
From 21 to step S24, the same operation as step S11 to step S14 shown in FIG. 5 is performed. If the measured zero point value Z2 is larger than the current zero point value Z1 in step S24, the zero point value Z1 is corrected upward by the correction value h in step S25. The zero point value after this correction is Z2
´

On the other hand, if the current zero point value Z1 is larger than the measured zero point value Z2, the zero point value Z1 is determined in step S26.
Is corrected downward by a correction value h. The corrected zero point value is set to Z2 '. Next, in step S27, a test command is sent to perform the test operation, and the test warning point value F2 is measured by the light emission of the test LED. The test LED is turned off by sending a test end command. Then, the current test reporting point value F1 is corrected to the test reporting point value F2.

Then, in step S28, it is determined whether or not the corrected zero point value Z2 'and the test reporting point value F2 are at predetermined levels. If it is not within the specified level range, terminal failure occurrence processing is performed in step S29,
Generate an abnormal alarm. If the zero point value Z2 ′ and the test reporting point value F2 are within the specified level range, then step S
From the zero point value Z2 'corrected by 30 and the test reporting point value F2,
Calculate and correct the conversion formula.

As a result, the zero point value, the test alarm point value, and the conversion formula are corrected correctly in a longer cycle than the zero point correction of once a day. FIG. 7 is a conversion characteristic diagram before and after zero correction according to the present invention. In FIG. 7, the horizontal axis represents the smoke density Y [% / m], and the vertical axis represents the detection data of the analog smoke sensor, that is, the AD conversion value X of the amount of light received by the light receiving element. This conversion characteristic is represented by, for example, a linear expression of Y = aX + b, and before correction, X = Z when Y = 0 [% / m].
Since it is 1, the constant b is b = −aZ1 and Y = aX−aZ1.

In this state, when the correction processing unit receives the zero point correction request command once an hour, the measured zero point value Z2 is measured for zero point correction, and the difference between the current zero point value Z1 and the measured zero point value Z2 is measured. If d = Z2-Z1 is smaller than the correction limit value L, the current zero point value Z1 is updated to the measured zero point value Z2. At the same time, the current test reporting point value F1 is changed by the difference d to be corrected to the test reporting point value F2. If the measured zero point value Z2 and the test reporting point value F2 are within the specified level range, The measured zero point value Z2 and the test reporting point value F2 are updated as valid values.

When the difference d is larger than the correction limit value L, the current zero point value Z1 is changed by the correction limit value L to obtain the zero point value Z2 '. At the same time, the current test reporting point value F1 is changed by the correction limit value L to correct it to the test reporting point value F2, and the zero point value Z2 ′ and the test reporting point value F2 are within the specified level range. For example, this zero point value Z2 ', test alarm point value F
Update 2 as a valid value.

Further, since X = Z2 was obtained as the AD conversion value X when Y = 0 [% / m] by the zero point measurement, the constant b becomes b = -aZ2, and the conversion equation is Y = It is corrected to aX-aZ2, and the conversion formula of the fire determination unit 19 is updated. Naturally, Y = 0 [% / m], X = Z2 and Y = 18 [% /
m] and X = F2, the same result can be obtained by calculating the conversion formula.

When the conversion type correction request command is issued once a day or once a week, when the measured value F2 of the test issue point is obtained, Y = 0 [% / m], X = Z2 and Y = 18%
/ M] and X = F2, a conversion formula is calculated and the fire determination unit 19 stores the correct conversion formula. The same correction method can be applied to the sensors shown in other embodiments as shown in FIGS.

The numerical values in the above embodiment are merely examples.
The present invention is not limited by these numerical values.

[0040]

As described above, according to the present invention, only the zero point value that does not affect fire monitoring is measured in a short cycle, the zero point value is corrected based on the measurement result, and the test generation is performed. Since the report point value is also pseudo-corrected and the conversion characteristic connecting both points is also corrected, more accurate zero point correction, test reporting point correction, and conversion characteristic correction are performed without increasing the number of unwarned states. Therefore, disaster prevention monitoring with high reliability becomes possible.

In this case, if the test reporting point is measured and corrected at a period longer than the zero point correction period of one day to one week, the disaster prevention monitoring with higher reliability becomes possible.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of a disaster prevention monitoring device according to the present invention.

FIG. 2 is a block diagram on the terminal side of the second embodiment of the disaster prevention monitoring device according to the present invention.

FIG. 3 is a block diagram of a terminal side of a disaster prevention monitoring device according to a third embodiment of the present invention.

FIG. 4 is a flowchart of zero-point correction control in the main MPU of the receiver.

FIG. 5 is a flowchart of zero correction processing in the sub MPU of the receiver.

FIG. 6 is a flowchart of conversion type correction processing in the sub MPU of the receiver.

FIG. 7 is a conversion characteristic diagram before and after zero correction.

[Explanation of symbols]

 1: Receiver 2, 3, 4, 5: Terminal 11: Main MPU 12-1, 12-2: Sub MPU 13: Operation part 14: Display part 15: Power supply part 16: Reception control part 17: Transmission control part 18 : Correction processing unit 19: Fire determination unit 21: Sensor unit 22: Transmission control unit 23: Correction processing unit 24: Conversion unit 25: Fire determination unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomonao Morota 2-1043 Kamiosaki, Shinagawa-ku, Tokyo Hochiki Co., Ltd. (72) Tetsuya Nagashima 2-1043 Kamiosaki, Shinagawa-ku, Tokyo No. Ho Chiki Co., Ltd. (72) Inventor Atsushi Nagai 2-1043 Kamiosaki, Shinagawa-ku, Tokyo Ho Chiki Co., Ltd. (72) Akira Kitajima 2-1043 Kamiosaki, Shinagawa-ku, Tokyo Ho Chiki Co., Ltd.

Claims (4)

[Claims] 1. A smoke sensor correction method for correcting the conversion characteristic between the light reception amount and smoke concentration of a smoke sensor for detecting smoke concentration or fire in a monitoring area based on a change in the light reception amount due to fire smoke. The first process of obtaining the difference between the current zero point value of the smoke detector and the newly measured zero point value, and if the difference is within the correction limit width, the zero point value is corrected to the newly obtained value. The second step of setting and the third step of setting the test reporting point value to a value corrected by the difference
And a fourth step of correcting the conversion characteristic into a conversion characteristic in which a corrected zero point value and a test alarm point value are connected to each other, the smoke sensor correction method. 2. The smoke sensor correction method according to claim 1, wherein when the difference exceeds a correction limit width in the second and third steps, the zero point value and the test alarm point value are set to the current values. A method for correcting a smoke sensor, which comprises correcting to a value to which a correction limit width is added. 3. The smoke detector correction method according to claim 1, further comprising: issuing a test report by a test command at an interval longer than the correction to obtain an accurate test report point. Sensor correction method. 4. The method of correcting a smoke sensor according to claim 1, wherein the first step is to average the zero point value of the smoke sensor up to the present time and a large number of newly measured values. A method of correcting a smoke sensor, characterized in that the difference between the obtained zero point value is obtained.