JPH09102090A - Gas detection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the gas detection system which can secure speediness and reliability while securing economy by providing a signal generation part, a signal processing part, a 1st signal transmission part, and a 2nd signal transmission part. SOLUTION: This gas detection system is provided with plural signal generation parts 1 which output gas detection signals, a signal processing part 6 which performs a required monitoring process according to the gas detection signals, the 1st signal transmission part 5 which transmits the gas detection signals from the generation parts 1 together to the processing part 6 in series, and the 2nd signal transmission part 4 which transmits the gas detection signals from the generation parts 1 individually to the processing part 6 in parallel. Thus, transmission lines 4 and 5 of two serial and parallel systems are secured and then even if one transmission system gets out of order, the gas detection signals can be transmitted to the signal processing part 6 by the other transmission line. Emergency information can speedily be transmitted as compared with a case wherein both the transmission are perform by serial transmission, and the facility cost can be suppressed as compared with a case wherein both the transmission are performed by parallel transmission.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disaster prevention monitoring system for plants such as electric power and oil, where a local signal processing unit monitors gas detection information in a part of an area, and a center signal processing unit monitors all gas detection information. Gas detection system.

[0002]

2. Description of the Related Art As shown in FIG. 4, a conventional gas detection system includes a plurality of signal generators 1 for outputting gas detection signals.
And a signal processing unit 6 that performs a required monitoring process based on the gas detection signal, and a signal transmission unit 5 that receives the gas detection signal from the signal generation unit 1 and serially transmits it to the signal processing unit 6. Was. Here, the signal generation unit 1 uses a gas detection unit 2 installed in a monitoring target area and a detection using a liquid crystal or the like that displays its output signal in a bar graph or the like with good visibility as shown in FIG. And a signal receiving unit 3 having a warning lamp 3b for displaying a warning when the detected gas concentration exceeds a predetermined threshold value 3c.
A plurality of the signal receiving units 3 are grouped together and installed in the monitoring target area. As shown in FIG. 2, the signal processing unit 6 is composed of an alarm display unit 6a and the like in which an alarm lamp is arranged in association with the gas detection unit 2, and at first glance which gas detection unit 2 detects the gas. It is configured so that it can be known whether it has been detected. In addition, the signal transmission unit 5 is installed in the vicinity of the signal reception unit 3 which is grouped into a plurality, and activates an alarm when an individual gas detection signal, that is, when the gas concentration reaches an alarm level, An input unit 5a for inputting a contact signal for stopping the alarm when the concentration has not reached the alarm level, a gas concentration signal obtained by converting the detected gas concentration into a voltage value, etc.
And a signal converter 5b for converting those input signals into a predetermined digital signal, and the converted digital signal RS-2.
A transmission control unit 5c for serial transmission using 32C or the like is provided.

[0003]

However, in the above-described conventional gas detection system, since the plurality of gas detection signals are serially transmitted from the signal transmission section 5 to the signal processing section 6, As the number of signal generators 1 increases, the time until the signals are transmitted to the signal processing unit 6 becomes longer, and in order to prevent the deterioration of the performance of the gas detection system, which requires an emergency, the signal transmission unit 5 is connected. There is an inconvenience that the number of signal generators 1 to be operated is limited.
Further, if the transmission line from the signal transmitting unit 5 to the signal processing unit 6 breaks down due to a disconnection or the like, the whole system will stop, which is not preferable for disaster prevention. The present invention has been made in view of the above problems, and an object of the present invention is to provide a gas detection system capable of securing promptness and reliability while securing economic efficiency.

[0004]

A first characteristic structure of a gas detection system according to the present invention is, as described in claim 1 of the claims, a plurality of signal generators for outputting gas detection signals. A signal processing unit that performs a required monitoring process based on the gas detection signal; a first signal transmission unit that collectively serially transmits the gas detection signal from the signal generation unit to the signal processing unit; The second point is that a second signal transmission section for individually transmitting the gas detection signal from the generation section to the signal processing section in parallel is provided. The second characteristic configuration is, in addition to the first characteristic configuration, the signal processing section is arranged in the vicinity of the signal generating section and is regional in addition to the first characteristic configuration as described in claim 2 of the scope of claims. The local signal processing unit includes a plurality of local signal processing units that perform monitoring processing, and a center signal processing unit that is disposed remote from the signal generation unit and performs overall monitoring processing, and the first signal transmission unit is the local signal processing unit. To the center signal processing unit, the second signal transmitting unit is configured to send a signal to the center signal processing unit, and a gas detection signal from the local signal processing unit to the center signal processing unit. It is configured to transmit.

The operation will be described below. According to the first characteristic configuration, by securing the two transmission lines of serial transmission and parallel transmission, even if one transmission line should fail, the other transmission line can be reliably used. The detection signal can be transmitted to the signal processing unit. Moreover, the serial transmission takes a long time to transmit, but the facility cost can be suppressed, while the parallel transmission has a contradictory feature that the facility cost is high, but the transmission time is short. In comparison, the emergency information can be transmitted quickly, and the equipment cost can be suppressed as compared with the case of transmitting both in parallel. According to the second characteristic configuration, in addition to the operation of the first characteristic configuration described above, the signal processing unit includes a plurality of local signal processing units that perform regional monitoring processing and a center signal that performs overall monitoring processing. Since it is divided into processing units and configured to perform serial transmission for each local signal processing unit, even if the number of signal generation units increases as a whole, the communication load on each local signal processing unit will extremely increase. Therefore, it is possible to efficiently perform hierarchical processing such as local processing and overall processing while suppressing the signal delay time due to serial transmission within an allowable range.

[0006]

[Effects of the Invention] That is, according to the present invention, it is possible to provide a gas detection system capable of securing promptness and reliability while securing economic efficiency.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. The gas detection system according to the present invention,
As shown in FIG. 1, a plurality of signal generators 1 that output gas detection signals, a signal processor 6 that performs a required monitoring process based on the gas detection signals, and a gas detection signal from the signal generator 1 are provided. A first signal transmitter 5 that serially transmits to the signal processor 6 collectively and a second signal transmitter 4 that individually transmits the gas detection signals from the signal generator 1 to the signal processor 6 in parallel. Is provided and configured.

The signal generating section 1 comprises a gas detecting section 2 installed in a monitored area and a signal receiving section 3 having a warning lamp 3d for displaying a warning when the detected gas concentration exceeds a predetermined threshold value. A plurality of the signal receiving units 3 are assembled and installed in the monitoring target area. In the signal receiving section 3, a detection gas concentration display section using a liquid crystal or the like for displaying an output signal level, which has been conventionally provided, is removed, and, as will be described later, one signal receiving section 3 is provided with 4 units. By connecting the gas detection unit 2 of the table, the cost can be reduced as compared with the conventional signal reception unit 3. More specifically, as shown in FIG. 3, the gas detector 2 is a hot-wire semiconductor type gas sensor 2 for detecting a target gas.
a and an amplifier 2b that amplifies the sensor output, an A / D converter 2c that converts the amplified signal, and a predetermined output signal, that is, a predetermined signal processing, that is, the sensor output adjustment described later and the sensor output to the signal receiving unit 3. It is configured by a microcomputer 2d for performing processing such as transmission of the signal, and operates by receiving power supply from the signal receiving unit 3. The microcomputer 2d is provided with an optical interface circuit 2e, and by communicating with the microcomputer 2d via the optical interface circuit 2e, adjustment of sensor output, that is, zero point adjustment while ensuring explosion-proof at the installation site. The gain is adjustable. That is,
Compared with the conventional maintenance performed by two people at the installation site and the signal receiving unit 3, it is possible to reduce the maintenance cost that the gain adjustment using gas can be performed by one person at the installation site.

The signal processing unit 6 is arranged in the vicinity of the signal generating unit 1 and is arranged remote from the signal generating unit 1 and a plurality of local signal processing units 7 for performing regional monitoring processing. Center signal processing unit 8 that performs various monitoring processes, the first signal transmitting unit 5 transmits a signal to the local signal processing unit 7, and the second signal transmitting unit 4
Is configured to transmit a signal to the center signal processing unit 8 and to transmit a gas detection signal from the local signal processing unit 7 to the center signal processing unit 8.

The first signal transmitting section 5 receives a signal from the signal receiving section 3 and converts it into a digital signal to which sensor identification information and the like are added, and serial communication such as RS232C for serial transmission. And outputs a gas detection signal to the local signal processing unit 7, that is, a gas concentration signal from the gas sensor 2a, and a contact signal that activates an alarm when the gas concentration signal exceeds a predetermined threshold value. On the other hand, the data transmitted from the local signal processing unit 7, for example, threshold data for alarm activation is output to the signal receiving unit 3. The second signal transmitting unit 4 is included in a microcomputer (not shown) of the signal receiving unit 3, and the signal receiving unit 3 individually outputs the analog gas concentration signal to the center signal processing unit 8. , Outputs a nodal signal as a parallel signal that activates an alarm when the gas concentration signal exceeds a predetermined threshold value.

The local signal processing unit 7 also inputs status signals such as the open / closed state of the gas flow control valve and the operating state of the ventilator for the device to be detected, and displays a gas alarm and a failure alarm for the device and the gas sensor 2a. , Gas concentration display, trend display, summary display, etc. The center signal processing unit 8 is composed of an interface unit 8a and, as shown in FIG. 2, an alarm display device 8b in which an alarm lamp is arranged in association with the gas detection unit 2. The interface unit 8a inputs a parallel signal from the second signal transmitting unit 4 and a state signal such as an open / closed state of a gas flow control valve related to a detection target device or an operating state of a safety device such as a ventilation device,
A PLC (programmable circuit) that outputs a predetermined gas detection signal to the alarm display device 8b in accordance with a preset logic.
It is composed of an interface circuit consisting of a logic controller). The center signal processing unit 8 outputs a gas detection signal and a status signal to a separately provided disaster prevention computer 9, and the disaster prevention computer 9 receives the gas detection signal and the status signal from the center signal processing unit 8. Together with the information displayed by the alarm display device 8b, it is possible to judge whether the system is normal or abnormal, and to execute comprehensive disaster prevention management for instructing output of countermeasures or the like when an abnormality occurs. The alarm display device 8b
Is a plurality of warning lights in which a contact signal transmitted in parallel from the local signal processing unit 7 and a contact signal which is one of gas detection signals from the interface unit 8a are connected by a wired OR circuit 8c, and other equipment. It is composed of a warning light that displays the state of.

A plurality of first signal transmitting sections 5 are connected to each of the plurality of local signal processing sections 7 described above, and a plurality of signal receiving sections are connected to each of the first signal transmitting sections 5. 3 is connected to each signal receiving unit 3, and a plurality of gas detecting units 2 are connected to each signal receiving unit 3, and four gas detecting units 2 are connected to each signal receiving unit 3 in the present embodiment. The central signal processing unit 8 performs overall management.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

1] Overall configuration of the gas detection system

FIG. 2 is an explanatory view of a main part.

FIG. 3 is a circuit block diagram of a main part.

FIG. 4 is an overall configuration diagram of a conventional gas detection system.

FIG. 5 is an explanatory diagram of a main part of a conventional gas detection system.

[Explanation of symbols]

 1 Signal Generation Section 4 Second Signal Transmission Section 5 First Signal Transmission Section 6 Signal Processing Section 7 Local Signal Processing Section 8 Center Signal Processing Section

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shoichi Matsuoka 3-3-22 Nakanoshima, Kita-ku, Osaka City, Osaka Prefecture Kansai Electric Power Co., Inc. (72) Tomoaki Iwami 2-chome, Mitsuyanaka, Yodogawa-ku, Osaka No. 5-4 New Cosmos Electric Co., Ltd. (72) Inventor Tadahiro Maeda 2-5-4 Mitsuyanaka, Yodogawa-ku, Osaka City, Osaka

Claims (2)

[Claims] 1. A plurality of signal generators (1) for outputting gas detection signals, a signal processor (6) for performing a required monitoring process based on the gas detection signals, and a signal generator (1) from the signal generator (1). A first signal transmission unit (5) for serially transmitting a gas detection signal to the signal processing unit (6) collectively and a gas detection signal from the signal generation unit (1) to the signal processing unit (6). A gas detection system provided with a second signal transmission unit (4) for individually performing parallel transmission. 2. The signal processing unit (6) is arranged in the vicinity of the signal generating unit (1) and performs a local monitoring process, and a plurality of local signal processing units (7) and the signal generating unit (7). 1) is arranged remotely and comprises a center signal processing unit (8) for performing overall monitoring processing. The first signal transmission unit (5) sends a signal to the local signal processing unit (7). The second signal transmission unit (4) is configured to transmit a signal to the center signal processing unit (8), and the local signal processing unit (7) transmits the signal to the center signal processing unit (7). 8. The gas detection system according to claim 1, wherein the gas detection signal is transmitted to 8).