Gas leakage detector is to detect the gas concentration detector, its core components for the gas-sensitive sensor, installed in the place where the gas leakage may occur, when the gas concentration in the air exceeds the set value of the detector will be triggered by the alarm, and the external sound and light alarm signals, if connected to the alarm host and the alarm center can be connected to the alarm, and can be automatically activated to start the exhaust equipment, close the gas pipeline valves, etc., to protect the safety of life and property. At the same time, it can automatically start the exhaust equipment, close the gas pipeline valves, etc., to protect the safety of life and property. In civil security projects, mostly used for home gas leakage alarm, but also widely used in various types of refineries, oil depots, chemical plants, liquefied petroleum gas stations and other places prone to combustible gas leakage.
People facing the threat of gas leakage caused by a variety of accidents, there really is not a complete solution? According to relevant experts, the use of gas leakage alarm is one of the important means of dealing with the invisible killer gas. Gas experts pointed out that the gas leakage or exhaust emissions and a large number of carbon monoxide is the root cause of gas poisoning response, such as the use of useful gas leakage alarms will be able to get a timely warning. Relevant departments after long-term testing also concluded that the gas alarm to prevent carbon monoxide poisoning accident efficiency of more than 95%.
Product Description Editor
Detecting gas: natural gas, liquefied petroleum gas, city gas (H2)
Working voltage: 220VAC or 110VAC, 12VDC-20VDC
Unique features:
(1) the new sensor drift auto-compensation function to truly prevent false alarms and omissions (2) alarms Failure to prompt the function, so that the user to replace and repair, to prevent the non-reporting
(3) MCU full control, operating temperature at -40 degrees ~ 80 degrees
Networking: wired networking (NO, NC)
Common alarms in order to reduce the cost of most of the selection of domestic devices, many manufacturers simply do not have a background in industrial product design to the generic electronic design ideas to guide the product design. Electronic design ideas to guide product design. The development process is not standardized, the test coverage is too low, there are potential life safety hazards, many manufacturers can not provide basic 3C certification.
In order to improve product reliability, the core components of the design, electronic chips and sensors usually need to be imported, and provide a variety of diagnostic and redundancy design to improve the safety and reliability of the system. Specifics can be found in the description of Inovation Environmental Safety Technology.
Installation Instructions Editor
1. Alarm Installation Location: Within 1.5 meters radius from the gas source, in a well-ventilated place:
(1) Liquefied gas is heavier than air, install it about 0.3 meters from the ground. (2) Natural gas, city gas, carbon monoxide, etc. are lighter than air and are installed about 0.3 meters from the ceiling.
2, can not be installed alarm location: corners, cabinets and other air is not easy to circulate the location; easy to be directly smoked fumes and other locations.
3, the gas alarm using a wide range of voltage, commonly 220V civil voltage products, general 12V voltage is rare, the way to get electricity with a telephone line type interface, suitable for higher security requirements of users, installed in the bedroom, compact and practical! See right
Application of production and sales of alarms you want in your mind 1, power light: green light, powered on, off when the alarm.
Alarm light: red, on when the alarm, stop the alarm off.
2. Turn on the power, the green light is on or flashing for 3 minutes, the alarm starts to work normally.
3, when the detected gas reaches the alarm point, the alarm starts to alarm, the green light is off, the alarm light is on, the buzzer sounds "B, B, B.......", when the concentration of the detected gas falls below the alarm point, the alarm stops alarming. (Carbon monoxide alarm has a delay function)
4, if you add a manual detection function, when you press the button, the green light is off, the alarm light is on, the buzzer sounds "B, B, B..." alarm.
5. If the function of exhaust fan is added, when the alarm is activated, the connected exhaust fan will start to remove harmful gases automatically.
6, if add the link robot or solenoid valve function, when the alarm alarm, has been linked to the robot or solenoid valve will automatically close the gas valve, so as to cut off the harmful gas source.
7, if you add the networking function, when the alarm alarm, the management center or control center at the same time to receive normally open and closed (NO, NC) signal. (For the addition of wireless function, the alarm host will receive 2-3 seconds of wireless signals)
After the alarm can be output to a pair of relay passive contact signals (normally open, normally closed jumper can be set), used to control the ventilation equipment or other equipment to provide normally open or normally closed alarm contacts.
When the concentration of combustible gas in the environment reaches the set threshold, it can send out sound and light alarm signals, and can output relay passive contact signals.
When the ambient combustible gas concentration falls below the response threshold, the detector in the alarm state will automatically return to normal operation.
Installation and Use Editor
The gas alarm consists of a detector and an alarm control mainframe, which is widely used in petroleum, gas, chemical industry, oil depots and other petrochemical industries where toxic gases exist to detect leakage in indoor and outdoor hazardous places, and is an important instrument to ensure production and personal safety. When toxic gases exist in the place to be measured, the detector will convert the gas signal into a voltage signal or current signal to be transmitted to the alarm instrument, which displays the percentage concentration value of the lower explosive limit of toxic gases. When the concentration of toxic gases exceeds the alarm set value when the sound and light alarm signal prompts the staff on duty to take timely safety measures to avoid explosion accidents.
1. Application considerations, gas alarm fixed installation once in place, the location is not easy to change, the specific application should consider the following points.
(1) to find out what the device to be monitored may leak points, analyze their leakage pressure, direction and other factors, and draw a distribution map of the location of the probe, according to the severity of the leakage is divided into Ⅰ, Ⅱ, Ⅲ three levels.
(2) According to the direction of airflow, wind direction and other specific factors in the place where it is located, determine the direction of leakage of toxic gases when a large number of leaks occur.
(3) According to the density of the leaking gas (greater or less than air), combined with the air flow trend, the three-dimensional flow trend of the leakage is synthesized into a map, and the downstream position of its flow to make the initial set point program.
(4) Study the leakage state of the leakage point is a micro-leakage or jet. If it is a micro-leakage, the location of the set point should be closer to the leakage point. If it is a jet leak, then slightly away from the leak. Combining these conditions, the final setup plan is formulated. In this way, the number and variety of purchases can be estimated.
(5) for the existence of large toxic gas leaks, according to the relevant provisions of every 10-20m apart should be set up a detection point. For unmanned small and discontinuous operation of the pump room, need to pay attention to the possibility of toxic gas leakage, generally should be installed in the downwind of a detector.
(6) for hydrogen leakage places, should be installed in the detector leakage point above the plane.
(7) for the gas density greater than the air medium, should be installed in the detector below the leak point below the plane, and pay attention to the characteristics of the surrounding environment. For places where toxic gases tend to accumulate should pay special attention to the setting of the safety monitoring point.
(8) for the open toxic gas diffusion escape environment, if the lack of good ventilation, it is also easy to make a part of the air in the toxic gas content close to or reach the lower limit of the explosion concentration, these are not to be ignored safety monitoring points. According to the analytical results of on-site accidents, more than half of them are caused by incorrect installation and calibration. Therefore, it is necessary to introduce the correct installation and calibration considerations to minimize failures.
2. Gas alarm installation precautions
(1) alarm probe is mainly in contact with the detection element of the combustion gas sensor, by the platinum wire coil wrapped with alumina and adhesive composition of the sphere, the outer surface of which is attached to the platinum, palladium and other rare metals. Therefore, must be careful when installing, to avoid dropping the probe.
(2) The installation height of the alarm should generally be 160-170cm, so as to facilitate the maintenance personnel to carry out routine maintenance.
(3)The alarm is a safety instrument with sound and light display function, and should be installed in the place where the staff can easily see and hear in order to eliminate the hidden danger in time. (4) The alarm can not be around the strong electromagnetic field (such as high-power motors, transformers) that have an impact on the work of the instrument.
(5) The density of the measured gas is different, the installation position of the indoor probe should be different. When the density of the measured gas is less than the air density, the probe should be installed 30cm away from the roof, downward direction; on the contrary, the probe should be installed 30cm from the ground, upward direction. The controller adopts three-core shielded wire to connect with the detector (Note: the diameter of single-core wire is not less than 0.75mm national standard wire, depending on the actual distance), and the shielding layer is connected to the controller case and reliably grounded. When the RVV cable is used, it should be threaded through a metal pipe and the metal pipe should be grounded reliably.
Construction wiring diagram of gas alarm
Refer to the wiring diagram of the controller and detector, connect the corresponding terminals of the controller and detector wiring mode will be input to the controller terminals and detector terminals corresponding to the corresponding ◆ Output terminals and linkage equipment connection ▲. When the exhaust fan and other inductive devices to meet the conditions of less than or equal to 5A/220VAV, can be directly connected to the output terminal, but as far as possible to avoid the load equipment is directly connected to the output terminal, when the load equipment is greater than 5A/220VAV, must be connected to the external adapter equipment; ▲. When the load device is larger than 5A/220VAV, it must be connected to the external adapter; ▲. When carrying out all kinds of installation operations, the power needs to be disconnected first, otherwise it may burn out the mainframe. The detectors used with the controller are: point-type gas detector. Technical parameters: ◆ Detection principle: catalytic combustion type, electrochemical type ◆ Detecting gas: combustible gas, toxic gas ◆ Sampling method: natural diffusion ◆ Display error: ±5% F-S/±10%/±5×10mol/mol ◆ Response time: ≤30s ◆ Operating voltage: DC12V ~ 30V ◆ Rated power: ≤3W ◆ Temperature: -40 ℃ ~ 60 ℃ ◆ Humidity: ≤95% RH ◆ Connection cable: ≥95% of the total number of the gas detector. RH◆ Connection cable: ≥RVV3×0.75mm (national standard wire) ◆ Transmission distance: ≤1200m ◆ Explosion-proof grade: ExdⅡCT6 ◆ Installation: Fixed bracket, pipe, wall ◆ Installation screw: G1/2〃 Installation position: The detector should be installed in the place where the gas is easy to be leaked, and the specific position should be decided according to the specific gravity of the gas detected in comparison with the air. When the specific gravity of the gas to be detected is greater than the specific gravity of air, the detector should be installed at a distance of (30-60) cm from the ground, and the sensor part is downward. When the specific gravity of the gas to be detected is less than the specific gravity of air, the detector should be installed at a distance of (30-60) cm from the ceiling with the sensor part downward. In order to use the detector correctly and prevent the detector from malfunctioning, please do not install it in the following locations: ◆ Places directly affected by steam and grease smoke; ◆ Places with large air flow such as air supply ports, ventilating fans, and doorways; ◆ Places with a lot of water vapors and water droplets (Relative Humidity: ≥90%RH); ◆ Places with temperatures below -40℃ or above 55℃; and ◆ Places with a strong electromagnetic field.
Treatment Editor
1. Please open doors and windows immediately, turn off hazardous air sources, and do not turn on or off any electrical switches.
2. Immediately report to the gas management department for inspection and treatment by professionals.
3. After being treated by professionals, the alarm should be ventilated.
Emergency treatment editor
Due to gas leakage caused by the detector alarm and the use of automatic cut-off device action, do not turn on the lights or open any electrical switches; should immediately open the window to ventilate the detector, such as the red alarm indicator off, look for confirmation of the cause of gas leakage (can not confirm the cause should be contacted to deal with the relevant gas company), and excluded. After confirming that the detector does not continue to alarm (gas does not continue to leak), press the manual switch to turn on the automatic shut-off device to restore gas. Please do not touch the power supply of the home gas alarm, in case the detector can not work properly.
Technical Parameters Editor
Voltage Selection: AC 220V/AC110; DC9V-16V
Low Power Alarm Static Power Consumption: <0.5W (Calculated by 12VDC)
High Power Alarm Static Power Consumption: ﹤3.3W (Calculated by 220VAC)
Alarm Concentration: gas Hugh: liquefied gas 0.1% ~ 0.5%; natural gas 0.1% ~ 1%; city gas (H2) 0.1% ~ 0.5%; carbon monoxide: 1 ‰ ~ 0.4 ‰
Using the U.S. imported PIC 16F676 is the front of the world's best one of the IC
Gas response, recovery time: ≤ 30S Carbon monoxide response, recovery time: ≤200S Alarm volume: ≥70dB
Working environment: humidity ≤97% RH Temperature: -15℃-+50℃
Unique Features Editor
Automatic shut-off valve manipulator, in the gas alarm automatically close the total ball valve. It makes it possible to fully realize the 24-hour alarm service function.
(1) the new sensor drift automatic compensation function, according to the drift of the sensor and drift to truly prevent false alarms and omissions. This technology is the first of its kind in China
(2) Alarm fault prompting function, the sensor is damaged automatically prompted so that the user to replace and repair, to prevent non-reporting.
(3) MCU full control, working temperature at -40 degrees ~ 80 degrees. Manipulator can be automatically reset without manual reset, to ensure the first time in a timely manner governance
Combustible gases and carbon monoxide hazards to the human body
1, combustible gas concentration exceeds the lower limit of the explosion, when the fire (lighters, electrical switches, static electricity, etc.) will be exploded, resulting in injury.
2, carbon monoxide is a colorless, odorless, highly toxic gases, inhaled through the respiratory tract and the human hemoglobin combination, resulting in human hypoxia and poisoning.
3, city gas itself contains a large amount of carbon monoxide, so gas leaks, both the risk of explosion, but also the risk of carbon monoxide poisoning, in addition, gas, kerosene, wood and other incomplete combustion of carbon monoxide.
Whether it is natural gas, liquefied petroleum gas, or coal gas, due to a variety of reasons after the leak, when the indoor gas concentration exceeds the lower limit of the explosion, when the fire (lighters, electrical switches, static electricity, etc.) is bound to explode. Why gas poisoning? China's city of artificial coal gas composition is different, but contain more carbon monoxide, for example, Harbin gas containing carbon monoxide 13, Shanghai gas containing carbon monoxide 19, Qingdao gas containing carbon monoxide 21, Qinhuangdao gas containing carbon monoxide as high as 30. as we all know, carbon monoxide is a highly toxic gas, healthy people in the air containing carbon monoxide 1, 10 minutes to produce spasms, half an hour, will die. It is known that carbon monoxide is a very poisonous gas. Therefore, when coal gas leaks, there is both a danger of explosion and carbon monoxide poisoning (direct poisoning). In addition, carbon monoxide poisoning (exhaust poisoning) can also occur when using a gas water heater or coal stove with poor ventilation. What is meant by the lower explosive limit? It means the lowest concentration that will explode in air in the presence of fire, and the alarm concentration is set at less than 1/4 of the lower explosive limit. For example: methane (the main component of natural gas) explosion lower limit of 5.0 (50,000 ppm) propane (liquefied petroleum gas main component) explosion lower limit of 2.0 (20,000 ppm) hydrogen (the main component of coal gas) explosion lower limit of 4.0 (40,000 ppm) What are the causes of gas leakage? In any household, no matter how much care is taken, there are likely to be eventualities. Among them, mis-ignition, bubbling pots or wind blowing out, extinguishing the flame in the middle of the day, and the main valve not being tightly piped account for more than 70% of the causes of leakage. Why do alarms know about gas leaks? The core of a gas alarm is the gas sensor, commonly known as the "electronic nose". This is a unique resistance, when the "smell" of gas, the sensor resistance with the gas concentration and change, the gas reaches a certain concentration, the resistance reaches a certain level, the sensor can issue an audible and visual alarm. What do you mean by audible and visual alarm? When the gas leakage reaches the concentration of the alarm, the red indicator light of the alarm will be on, and the buzzer will emit the alarm sound of "Pai-Pai-Pai", so it is called acousto-optic alarm. Why does the gas alarm have an expiration date? The quality of the sensor, generally 1-2 years on the decline in performance, and therefore the loss of the alarm safety type. Alarm in which the other electronic components (such as transformers, capacitors, transistors, etc.) have a limited life expectancy, so even the advanced countries also stipulate that the expiration date of up to five years. In order to ensure safety, five years after the expiration of the alarm must be replaced with a new one.
Trivia Editor
Gas Leakage Alarm Principle
Very important gas safety equipment, it is the last protection of the safe use of city gas. Gas leakage alarm through the gas sensor to detect low concentrations of combustible gases in the surrounding environment, through the sampling circuit, the detection signal with analog or digital transmission to the controller or control circuit, when the concentration of combustible gases exceeds the value set in the controller or control circuit, the controller through the actuator or the implementation of the circuit to send an alarm signal or perform the closure of gas valves and other actions. Combustible gas alarm sensor to detect combustible gases are mainly oxide semiconductor type, catalytic combustion type, hot-wire type gas sensors, there are a small number of other types, such as chemical battery type sensors. These sensors are through the adsorption of combustible gases in the surrounding environment, the sensor surface to produce a chemical reaction or electrochemical reaction, resulting in a change in the electrophysical properties of the sensor.
Function of gas leakage alarm
Function can be divided into leakage alarms and leakage alarms that only have leakage alarms and detection alarms that can indicate the concentration of detected gas and have alarm functions; from the place of use can be divided into civil gas leakage alarms and commercial alarms. Residential alarms are usually independent in the residential use of gas alarms, the function is relatively simple; commercial alarms are mainly used for gas transportation, storage sites, the use of gas and gas leakage may be factories and public **** places. City gas specification in the basement, semi-basement, the ground confined space of the gas room, the building's pipeline wells, closed metering room, etc. to install gas alarms. Building and gas related codes and regulations also recommend the use of residential gas leak alarms.
Installation Steps Editor
Installation Method
In the selected wall location, corresponding to the random mounting plate on the two mounting holes to make a good hole marking (the hook on the plate should be horizontal towards the top);
Punching the mounting holes, put in the random mounting rubber plugs, and then use the random tapping screws to fix the mounting plate to the wall;
The three holes at the back of the body aligned with the mounting plate on the three holes on the back of the body to align with the fixed hooks on the mounting plate and hang the body;
Connect the relevant output signal lines and then turn on the power.
Status test
Normal monitoring state: after 3 minutes of power on warm-up, the green light will glow steadily, indicating that the alarm is working normally in the monitoring state; during the warm-up process, the alarm may emit a "beep beep beep beep" sound and the red light will flash, and disappear before the green light is on.
Site alarm status: When the gas content in the air around the alarm exceeds the alarm point, the alarm will emit "beep...beep..." intermittent ear-piercing chirping, while the red light flashes to remind the user as soon as possible for the scene processing; alarm output status: After the sound and light alarm lasts for 10 seconds, different specifications of the alarm will output different types of alarm signals to notify the alarm system or start the corresponding linkage device.
Features Editor
(1) Ventilation port: gas (natural gas, liquefied petroleum gas, city gas) enters the induction chamber through the gap between the alarm face shell and bottom shell. In order to allow air to circulate properly, do not install the alarm in a very dirty, dusty or greasy place.
(2) Sensor: The sensor applies semiconductor technology, which is extremely sensitive to combustible gases and avoids false alarms.
(3) Buzzer: The volume is up to 85 decibels, which occurs to alert you to potential dangers, and the alarm is in the form of: continuous ringing.
(4) warm-up: when the alarm is energized, it needs to be warmed up for 2-3 minutes, and it will not alarm within 2-3 minutes of energization.