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Product Introduction
Gas Alarm Detector is the core equipment of industrial safety monitoring systems, equipped with high-precision gas sensors to real-time monitor the concentration of flammable gases, toxic and harmful gases (such as CO, H2S) and oxygen in the environment. It automatically triggers sound and light alarm signals when the concentration exceeds the safety threshold, providing continuous online monitoring and leakage early warning guarantees for high-risk scenarios such as petrochemical industry, gas stations, and sewage treatment plants, widely used in industrial explosion protection, environmental monitoring and safety production management fields.
Core Product Advantages
1. Accurate Detection & Rapid Response
Adopts electrochemical/catalytic combustion/infrared principle sensors with high resolution (0.1%LEL for flammable gases, 0.1ppm for toxic gases) and response time ≤30s, enabling quick capture of gas leakage signals.
2. Stable & Durable with Strong Anti-Interference
Explosion-proof housing design (IP65/IP67 protection grade), high temperature, corrosion and electromagnetic interference resistance, suitable for complex industrial environments with a service life ≥2 years.
3. Intelligent & Easy to Operate and Maintain
Large screen displays real-time concentration and alarm status, supports infrared remote control/magnetic rod calibration for cover-free maintenance; modular design allows quick sensor replacement.
4. Multi-Scenario Adaptation & Strong Compatibility
Capable of detecting over 30 gas types, supports 4-20mA/RS485 signal output, compatible with DCS/PLC control systems for remote monitoring.
5. Multi-Level Protection & High Reliability
Dual high/low concentration alarm settings, sound-light + relay output linkage, and self-diagnosis function to avoid false/missed alarms.
Main Components
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Sensor: As the core component, it is responsible for detecting the concentration of flammable gases. Common types include:
- Catalytic combustion sensor: Suitable for most flammable gases. It generates signals through temperatue changes of components caused by gas combustion.
- Semiconductor sensor: Features high sensitivity and fast response, but has relatively poor selectivity.
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Alarm controller: Receives signals from the sensor, processes and judges them. When the gas concentration exceeds the set threshold, it triggers the alarm device.
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Alarm device: Usually includes an acoustic-optical alarm, which emits a sharp sound and flashing lights to alert on-site personnel.
Types of Detectable Gases
Specify the flammable gases that can be detected, such as methane (CH4), propane (C3H8), hydrogen (H2), acetylene (C2H2), ethanol (C2H5OH), etc.
Some instruments support multi-gas detection by replacing sensors (multi-gas type), and the range of compatible gases should be indicated.
Detection Principles
Corresponding to the sensor types:
- Catalytic combustion type: Suitable for most flammable gases with a wide detection range.
- Semiconductor type: High sensitivity, suitable for low-concentration detection.
- Infrared type: Strong anti-toxicity and long service life, often used for specific gases such as methane.
Environmental Adaptation Parameters
Operating Temperature
- Fixed type: -40ºC~+70ºC (for industrial scenarios, designed to withstand high and low temperatures).
- Portable type: -20ºC~+50ºC (for daily inspections, in relatively mild environments).
Exceeding this range may affect sensor performance, requiring additional protection (such as thermal insulation or heat dissipation devices).
Operating Humidity
Typically 10%~95% RH (non-condensing). High-humidity environments (e.g., humid workshops) require moisture-proof design to prevent short circuits or sensor failure.
Explosion-Proof Rating
A critical parameter, such as Ex d II CT6 (flameproof type, suitable for Zone II, Category C explosive areas, with a maximum surface temperature ≤85ºC). The rating must be selected based on the explosion hazard level of the usage site to avoid the instrument becoming an ignition source.
Protection Rating
For example, IP65 (completely dust-tight, protected against low-pressure water jets). Outdoor or dusty environments require a higher protection rating (IP66/IP67).
Alarm Methods
- Acoustic-optical alarm: Sound intensity ≥85dB (at 1 meter distance); light is red flashing (visual distance ≥20 meters).
- Others: Vibration alarm (for portable devices), remote alarm (linked with control systems).
Signal Output
- Analog quantity: 4-20mA current signal (long transmission distance, suitable for connecting to PLC/DCS systems).
- Digital quantity:
- RS485 (Modbus protocol, facilitating data upload to monitoring platforms).
- Switch quantity (for interlocking with valves/fans, usually with a capacity of AC220V 5A).
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Working Principle
1. Gas Sampling: Collect ambient gas via pump suction or diffusion mode and send it to the sensor detection chamber.
2. Signal Conversion: The sensor reacts with the target gas (e.g., catalytic combustion, electrochemical reaction) to generate an electrical signal proportional to the gas concentration.
3. Data Processing: The built-in microprocessor amplifies, filters and AD-converts the electrical signal to calculate and display the gas concentration value.
4. Alarm Judgment: When the detected concentration exceeds the preset alarm threshold, it drives the buzzer and LED indicator to emit sound-light alarms, and outputs switch/analog signals to link external devices (e.g., solenoid valves, exhaust fans).
5. Status Feedback: Upload concentration data and alarm status to the control system in real time for remote monitoring and data traceability.
Maintenance and Calibration
To ensure the accuracy and reliability of the instrument's detection, regular maintenance and calibration are required:
- Clean the sensor regularly to prevent dust, oil stains, etc., from affecting detection accuracy.
- Calibrate with standard gas regularly according to the instructions to ensure the alarm threshold is accurate.
- Check whether the alarm device works normally to ensure the sound and light alarm functions are intact.
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https://hzzexuan.en.made-in-china.com/product/lpiYJfxGjjkt/China-Biogas-Flare-System-for-Industrial-Methane-Combustion.html
Address: Huji Industrial Park, Deshang Expressway, Mudan District, Heze City, Shandong Province, China
Business type: Manufacturer/factory, trading company
Business scope: manufacturing and processing machinery
Management system certification: ISO9001:2015 ISO45001:2018 ISO14001:2015
Main products: Ground flare, Biogas flares, flare stack,
Thermal Oxidation Furnace, Flue gas purification equipment
Heze Zexuan Equipment Manufacturing Co., Ltd. is an enterprise engaged in the manufacture of special equipment for environmental protection; sales of special equipment for environmental protection; application of industrial automation technology; sales of power electronic components; research and development of mechanical equipment; sales of intelligent instruments and meters; manufacturing of intelligent instruments and meters; research and development and promotion of comprehensive utilization of waste gas and VOCs treatment technology.
The company's main products and service directions: manufacturing of ground torches, elevated torches, waste gas venting torches, biogas torches, three waste incinerators, and wastewater treatment equipment, industrial automation and DCS system applications, wastewater treatment projects, VOCs treatment equipment and engineering construction, petrochemical accessories and instrument sales, petrochemical equipment installation, maintenance and repair, etc.; support product customization services and OEM services in the same industry, from design to manufacturing, installation, commissioning, and after-sales one-stop service.
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Q: What is the function of a combustible gas alarm?
A: Real-time gas concentration monitoring with audible-visual alarm to prevent explosions.
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Q: Which gases can it detect?
A: Methane, propane, hydrogen, acetylene, ethanol, natural gas, etc.
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Q: What's the difference between fixed and portable models?
A: Fixed: 24/7 on-line monitoring; Portable: for on-site inspection.
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Q: What does explosion-proof rating mean?
A: Safety level for use in hazardous areas (e.g., Ex d II CT6).
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Q: What alarm methods are available?
A: Audible-visual alarm, optional vibration and remote alarm.
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Q: What signal outputs does it support?
A: 4-20mA, RS485 (Modbus), and switch output.
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Q: What sensor types are used?
A: Catalytic combustion, semiconductor, and infrared sensors.
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Q: What are the operating conditions?
A: Fixed: -40ºC~+70ºC, 10%~95%RH (non-condensing).
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Q: What maintenance is required?
A: Regular cleaning, calibration with standard gas, and alarm function testing.
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Q: What to note during installation?
A: Install at correct height, avoid EMI, and ensure proper grounding.
Welcome to contact us for a free quotation and customized services.
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