1. Introduction
The Bosean BH-4M is a portable, high-performance multi-gas detector designed for monitoring oxygen (O2), hydrogen sulfide (H2S), carbon monoxide (CO), and combustible gases (LEL/CH4) simultaneously. This device is engineered with advanced sensor technology to provide accurate and reliable gas concentration readings, ensuring safety in various industrial and environmental settings. Its robust design and intuitive interface make it an essential tool for personal safety and environmental monitoring.
The BH-4M is suitable for a wide range of applications including oil extraction, metallurgical manufacturing, chemical medicine, gas pipelines, gas stations, laboratories, garbage stations, and animal husbandry.
Image: The BH-4M detector is utilized across diverse environments such as oil extraction, chemical plants, gas stations, and laboratories.
2. Package Contents
Upon unpacking, please verify that all items listed below are present and in good condition:
- Gas Detector (BH-4M) x 1
- Calibration Cover x 1
- English User Manual x 1
- Qualified Certificate x 1
- Charging Adaptor x 1
- Type-C Charging Cable x 1
- Ventilation Hose x 1 (for pump type)
- Screwdriver x 1
- Carrying Case (optional, depending on purchase)
Image: Illustration of standard package contents for the BH-4M gas detector.
3. Product Overview
The BH-4M detector features a robust design with an HD color screen and intuitive controls. It is available in two main configurations: Natural Diffusion Type and Pump Type.
3.1. Device Components
Image: Labeled diagram of the BH-4M detector (pump type) highlighting key components.
- Gas Hole: Inlet for gas detection.
- LED: Indicator light for status and alarms.
- Alarming Lights: Visual alarm indicators.
- Buzzer Hole: Emits audible alarm sounds.
- Type-C Interface: For charging and data transfer.
- Gas Sampling Pump: (Pump type only) Actively draws gas samples.
- HD Color Screen: Displays gas concentrations, time, and other information.
- Control Buttons: RECORD, MENU, CURVE, and navigation arrows for operation.
3.2. Detector Types
The BH-4M offers two detection methods to suit different needs:
Image: Comparison of the Natural Diffusion Type and Pump Type BH-4M detectors.
- Natural Diffusion Type: The gas in the inspected area flows freely with the air, and the sample gas flows into the instrument for inspection. This type is ideal for general area monitoring.
- Pump Type: Features an active gas sampling pump for fast detection speed and long-distance measurement of dangerous areas, enhancing maintenance personnel safety.
4. Setup
4.1. Initial Charging
Before first use, fully charge the device. Connect the provided Type-C charging cable to the detector's Type-C interface and the charging adaptor to a power outlet. The battery indicator on the screen will show charging status. A full charge typically provides over 10 hours of continuous use without the pump, and over 8 hours with the pump activated.
Image: Battery life illustration for the BH-4M detector.
4.2. Power On/Off
- Power On: Press and hold the power button (usually the 'Home' icon button) for a few seconds until the screen lights up and the device initializes.
- Power Off: Press and hold the power button until a shutdown prompt appears, then confirm to power off.
4.3. Pre-Operation Check
Before each use, ensure the following:
- The device is fully charged.
- The gas inlet is clear of obstructions.
- For pump type, ensure the ventilation hose is securely attached if required for remote sampling.
- Perform a fresh air calibration if necessary (refer to Maintenance section).
5. Operation
5.1. Basic Navigation
The BH-4M features a simple three-button interface for intuitive operation:
Image: The three-button interface and Type-C port of the BH-4M.
- RECORD Button: Used to start/stop data logging.
- MENU Button: Accesses the main menu for settings and configurations.
- CURVE Button: Displays historical gas concentration curves.
- Arrow Buttons: Navigate through menu options and adjust values.
5.2. Gas Detection
Once powered on, the device will automatically begin detecting the four specified gases (O2, H2S, CO, LEL). The HD color screen displays real-time concentrations for each gas. For pump-type detectors, ensure the pump is activated for active sampling in the desired area.
5.3. Alarm Functions
The BH-4M is equipped with four types of alarms to alert users to hazardous gas levels:
- Light Alarm: Flashing LED and alarming lights.
- Sound Alarm: Audible buzzer.
- Vibration Alarm: Tactile feedback.
- Screen Display Alarm: Visual alerts on the HD color screen.
Alarm thresholds (High/Low values, STEL - Short Term Exposure Limit, TWA - Time Weighted Average, OL - Over Limit) can be set via the MENU. Refer to the 'Specifications' section for default alarm points.
5.4. Data Storage and Analysis
The device can store up to 100,000 data records. These records can be imported into a computer for sorting and analysis using the Type-C data cable. This feature allows for comprehensive monitoring and reporting of gas exposure over time.
Image: Data transfer and analysis capability of the BH-4M.
6. Maintenance
6.1. Cleaning
Regularly clean the exterior of the detector with a soft, damp cloth. Do not use abrasive cleaners or solvents. Ensure the gas inlet and buzzer hole are free from dust and debris.
6.2. Calibration
Periodic calibration is crucial for maintaining the accuracy of the gas detector. Use the provided calibration cover for fresh air calibration. For span calibration with specific gas concentrations, consult the detailed instructions in the full English User Manual or contact customer support. Always perform calibration in a clean, fresh air environment.
6.3. Battery Care
To prolong battery life, avoid fully discharging the device frequently. Charge the device regularly, especially if it will be stored for an extended period.
7. Troubleshooting
If you encounter any issues with your Bosean BH-4M detector, please refer to the following common problems and solutions:
- Device not powering on: Ensure the battery is charged. Connect to the charger and try again.
- Inaccurate readings: Perform a fresh air calibration. Check for obstructions at the gas inlet. Ensure sensors are not expired (check device settings or contact support).
- No alarm activation: Verify alarm thresholds are set correctly in the MENU. Check if alarm functions (sound, vibration) are enabled.
- Pump not working (Pump Type): Check for blockages in the ventilation hose. Ensure the pump function is enabled in settings.
- Data transfer issues: Ensure the Type-C cable is securely connected to both the detector and the computer. Check computer's device manager for driver issues.
For persistent issues or complex problems, please contact Bosean customer support.
8. Specifications
8.1. General Specifications
- Model: BH-4M
- Detected Gases: O2, H2S, CO, LEL (CH4)
- Display: HD Color Screen
- Alarm Types: Light, Sound, Vibration, Screen Display
- Alarm Functions: High/Low value, STEL, TWA, OL
- Battery: 2500mAh Lithium Battery
- Continuous Use: >10 hours (without pump), >8 hours (with pump)
- Data Storage: Up to 100,000 records
- Interface: Type-C for charging and data transfer
- Protection: Waterproof, Dustproof (Three-proof design with high-strength engineering plastics/composite non-slip rubber)
- Motor (Pump Type): Built-in micro powerful motor (stable flow, efficient performance, copper motor, long life)
8.2. Dimensions and Weight
Image: Physical dimensions and weight for both detector types.
- Natural Diffusion Type:
- Height: 150mm
- Width: 69mm
- Depth: 55mm
- Weight: Approximately 335g
- Pump Type:
- Height: 160mm
- Width: 69mm
- Depth: 75mm
- Weight: Approximately 372.5g
8.3. Gas Detection Parameters
The following table outlines the detection parameters for various gases supported by the BH-4M. Note that the BH-4M specifically detects O2, H2S, CO, and LEL (CH4) as standard. Other gases listed below may be available with specialized sensor configurations or optional ranges.
Image: Comprehensive gas selection table with detection parameters.
| Gas Name | Measurement Range | Optional Range | Resolution | Alarm Points (Low/High) |
|---|---|---|---|---|
| Combustible Gas EX | 0-100%LEL | 0-100%LEL (Infrared) | 1%LEL/1%vol | Low: 20 / High: 50 |
| Oxygen O2 | 0-30%vol | 0-30%vol | 0.1%vol | Low: 19.5% / High: 23.5%vol |
| Hydrogen Sulfide H2S | 0-100ppm | 0-50/2000/5000ppm | 0.1ppm | Low: 10 / High: 20 ppm |
| Carbon Monoxide CO | 0-1000ppm | 0-500/2000/5000ppm | 1ppm | Low: 50 / High: 150 ppm |
| Carbon Dioxide CO2 | 0-5000ppm | 0-1%/5%/10%vol (Infrared) | 1ppm/0.1%vol | Low: 1000 / High: 2000 |
| Nitric Oxide NO | 0-250ppm | 0-250ppm | 1ppm | Low: 50 / High: 150 ppm |
| Nitrogen Dioxide NO2 | 0-20ppm | 0-50/1000ppm | 0.1ppm | Low: 5 / High: 10 ppm |
| Sulfur Dioxide SO2 | 0-20ppm | 0-50/1000ppm | 0.1/1ppm | Low: 5 / High: 10 ppm |
| Chlorine CL2 | 0-20ppm | 0-100ppm | 0.1ppm | Low: 5 / High: 10 ppm |
| Hydrogen H2 | 0-1000ppm | 0-5000ppm | 1ppm | Low: 50 / High: 150 ppm |
| Ammonia NH3 | 0-100ppm | 0-50/500/1000ppm | 0.1/1ppm | Low: 20 / High: 50 ppm |
| Phosphine PH3 | 0-20ppm | 0-20/1000ppm | 0.1ppm | Low: 5 / High: 10 ppm |
| Hydrogen Chloride HCL | 0-20ppm | 0-500/1000ppm | 0.001/0.1ppm | Low: 5 / High: 10 ppm |
| Chlorine Dioxide CLO2 | 0-50ppm | 0-10/100ppm | 0.1ppm | Low: 5 / High: 10 ppm |
| Hydrogen Cyanide HCN | 0-20ppm | 0-100ppm | 0.1/0.01ppm | Low: 10 / High: 20 ppm |
| Ethylene Oxide C2H4O | 0-100ppm | 0-100ppm | 1/0.1ppm | Low: 20 / High: 50 ppm |
| Ozone O3 | 0-10ppm | 0-20/100ppm | 0.1ppm | Low: 2 / High: 5 ppm |
| Formaldehyde CH2O | 0-20ppm | 0-50/100ppm | 1/0.1ppm | Low: 5 / High: 10 ppm |
| Hydrogen Fluoride HF | 0-10ppm | 0-1/10/50/100ppm | 0.01/0.1ppm | Low: 2 / High: 5 ppm |
| Xylene/Toluene | 0-20ppm | 0-1/10/50/100ppm | 0.01/0.1ppm | Low: 5 / High: 10 ppm |
*For other unlisted gases and ranges, please contact customer service.
9. User Tips
- Always ensure the device is fully charged before critical operations to avoid interruptions.
- Regularly check the gas inlet for any blockages, especially in dusty environments.
- For pump-type detectors, ensure the ventilation hose is clean and free of kinks for optimal sampling.
- Store the detector in a clean, dry place away from extreme temperatures and direct sunlight.
- Familiarize yourself with the alarm settings and ensure they are appropriate for your specific application and safety standards.
10. Warranty and Support
The Bosean BH-4M Multi Gas Detector is manufactured to high-quality standards. For warranty information, technical support, or service inquiries, please refer to the official documentation included with your product or contact your authorized Bosean dealer or customer service representative. Keep your purchase receipt as proof of purchase for warranty claims.