YT-98H Fixed Multi-Gas Detector with 4-in-1 CO/H₂S/O₂/LEL Monitoring Built-in Vacuum Pump and Imported Sensors
The YT-98H series is a fixed multi-gas detector designed for continuous, simultaneous monitoring of up to six gases. In its standard four-gas configuration, it tracks CO (0-1000ppm, 1ppm), H₂S (0-100ppm, 0.1ppm), O₂ (0-30%VOL, 0.1%VOL), and LEL (0-100%LEL, 1%LEL) using electrochemical cells for the first three and catalytic bead sensing for combustibles.
Central to its design is an internal vacuum pump that actively draws sample air at 0.5 L/min, with a continuous service life exceeding 12,000 hours. This active extraction delivers T90 response within 20 seconds and allows the detector to be placed in safe, accessible areas while sampling from ducts, vessels, or confined spaces - reducing the need for personnel to enter hazardous zones for routine checks.
The unit provides standard 3-wire 4-20mA, RS485 Modbus, and one relay output, with optional second relay, HART, or voltage signals (0-10V, 0-5V, 1-5V) for flexible integration with control systems. Configuration is performed without opening the enclosure, using the supplied infrared remote control or an optional magnetic wand - preserving the flameproof seal in explosive atmospheres.

| Parameter | Value |
|---|---|
| Gases detected | CO, H₂S, O₂, LEL (expandable to 6 gases) |
| Detection principles | Electrochemical (CO/H₂S/O₂), Catalytic combustion (LEL) |
| Measuring ranges | CO: 0-1000ppm; H₂S: 0-100ppm; O₂: 0-30%VOL; LEL: 0-100%LEL |
| Resolution | CO: 1ppm; H₂S: 0.1ppm; O₂: 0.1%VOL; LEL: 1%LEL |
| Accuracy | ≤ ±2% FS (sensor-dependent) |
| Response time (T90) | ≤20 seconds (sensor-dependent) |
| Repeatability | ≤ ±1% |
| Pump flow rate | 0.5 L/min |
| Pump continuous life | >12,000 hours |
| Zero shift | ≤ ±1% FS/year |
| Display | 2.4-inch colour LCD, 320×240 resolution |
| Display content | Gas formula, concentration, unit, pump status, alarm status |
| Languages | Chinese, English |
| Alarm (optional) | Sound/light (integrated or external); user-adjustable high/low setpoints |
| Fault alarm | Sensor disconnect alert |
| Standard outputs | 3-wire 4-20mA, RS485 Modbus, 1 relay |
| Configuration | Infrared remote control (standard); magnetic wand (optional) |
| Operating temperature | -10°C to +55°C |
| Humidity | 0-95% RH (non-condensing) |
| Enclosure material | Die-cast aluminium |
| Power supply | 12-24V DC |
| Dimensions (H×W×D) | 286 × 202 × 96 mm |
| Weight | 3.4 kg (3.8 kg with alarm light) |
| Explosion-proof grade | Ex d IIC T6 Gb |
| Protection grade | IP65 |
- Built-in vacuum pump - Delivers a steady flow of 0.5 L/min with a continuous operating life exceeding 12,000 hours. Provides faster response (T90 ≤20s) and enables remote sampling from hard-to-reach areas.
- Multi-gas capability - Monitors up to 6 gases simultaneously, reducing installation space and cost.
- Non-intrusive configuration - Standard infrared remote control allows zero/span calibration, alarm setpoint adjustment, and parameter changes without opening the enclosure - preserving explosion-proof integrity in hazardous zones.
- Rich display interface - 2.4-inch industrial-grade colour LCD with 320×240 resolution and 120-degree wide viewing angle. Shows gas formula, real-time concentration, pump status, alarm indicators, and max/min values.
- Flexible output options - Standard 3-wire 4-20mA, RS485 Modbus, and one relay. Optional second relay, HART, and voltage outputs - compatible with PLC, DCS, and SCADA systems.
- Rugged construction - Die-cast aluminium housing, IP65 rated, and certified Ex d IIC T6 Gb for Zone 1 and 2 hazardous areas.
- Confined space entry - Install the detector outside manholes, tanks, or vessels while sampling inside. Perform pre-entry gas checks and monitor continuously during worker occupancy.
- Underground utilities - Sample from lift stations, vaults, and sewer lines to detect H₂S and methane before personnel enter.
- Ductwork and HVAC systems - Mount the detector in a mechanical room and draw samples from air ducts to check for refrigerant leaks or combustion by-products.
- Storage tanks and vessels - Sample headspace during cleaning, inspection, or maintenance to detect flammable or toxic residues.
- Flue gas stacks - With the optional high-temperature pre-treatment system, sample flue gas up to 1200°C for combustion efficiency monitoring.
- Oil and gas refineries - Sample from flare stacks, catalytic cracker enclosures, and amine treatment areas for H₂S and LEL.
- Chemical plants - Monitor reactor vent lines and storage tank headspaces for toxic intermediates and flammable releases.
- Sound/light alarm (integrated or external)
- Water-vapour filter cartridge
- Automatic dehumidification & drainage system (ambient temperature)
- Manual dehumidification & drainage system (ambient temperature)
- High-temperature flue gas pre-treatment system (up to 1200°C)
Shenzhen YuanTe Technology Co., Ltd. (brand: Safegas) was founded in 2010 and specializes in the research, development, manufacturing, and sales of gas detection equipment and integrated systems. With over 16 years of industry experience, the company serves sectors including oil and gas, chemicals, environmental protection, electronics, municipal engineering, agriculture, and household appliances.
All products are manufactured under ISO9001 and ISO45001 management systems and hold international certifications such as IECEx, ATEX, and EMC. With an annual production capacity exceeding 80,000 units, YuanTe Technology supplies gas detection solutions to customers worldwide, backed by a global distribution network and round-the-clock customer support.
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