
Fixed gas Dectection Systems- 303 Series
The Series 303 Fixed Type Gas Alarm is a compact gas monitoring system designed for continuous detection of combustible gases, oxygen, and toxic gases in industrial and marine environments. Manufactured by Tokaseiki Co., Ltd., the Series 303 combines reliable sensing technology with a corrosion-resistant construction, making it suitable for demanding applications where fixed-point gas monitoring is essential.
Description
The system features audible and visual alarm indication, optional analog signal outputs, and dry contact alarm outputs for integration with external monitoring and control systems. Its durable design and stable performance make it ideal for use in gas utility facilities, machinery spaces, storage terminals, chemical plants, and marine vessels.
Specifications
| Parameter | Value |
|---|---|
| Equipment | Fixed Type Gas Alarm |
| Manufacturer | Tokaseiki Co., Ltd. |
| Models | TS-303A, TO-303, TK-303 |
| Installation Type | Fixed Mounting |
| Detection Types | Combustible Gas, Oxygen, Toxic Gas |
| Alarm Indication | Audible Buzzer & Visual Alarm Lamp |
| Alarm Contact | Dry Contact 1C |
| Signal Output | Optional 4–20mA / 0–100mV |
| Power Supply | AC100V 50/60Hz |
| Optional Power Supply | DC12V / DC24V |
| Applications | Marine, Offshore, Industrial Facilities, Utility Systems |
Technical Specification
| Model | TS-303A | TO-303 | TK-303 |
|---|---|---|---|
| Gas Type | Combustible Gas | Oxygen | Toxic Gas |
| Detection Principle | Catalytic Combustion | Galvanic Cell | Electrochemical |
| Measurement Range | 0–100% LEL | 0–25% O₂ | Depends on gas type |
| Accuracy | ±5% FS | ±0.7% O₂ | ±5–10% FS |
| Alarm Setting | More than 1/10 FS | More than 1/10 FS | More than 1/10 FS |
| Alarm Accuracy | ±25% of alarm setting | ±25% of alarm setting | ±25% of alarm setting |
| Response Time | Within 30 sec | Within 10 sec | Within 30 sec |
| Operating Temperature | -10°C to 50°C | 0°C to 40°C | 0°C to 40°C |
| Humidity | Under 95% RH | Under 95% RH | Under 85% RH |
| Power Supply | AC100V 50/60Hz | AC100V 50/60Hz | AC100V 50/60Hz |
| Optional Power | DC12V / DC24V | DC12V / DC24V | DC12V / DC24V |
| Alarm Contact | Dry Contact 1C | Dry Contact 1C | Dry Contact 1C |
| Signal Output | 4–20mA / 0–100mV (Optional) | 4–20mA / 0–100mV (Optional) | 4–20mA / 0–100mV (Optional) |
Applications
- Marine Engine Rooms
- Offshore Platforms
- Gas Manufacturing Facilities
- Chemical Processing Plants
- Petrochemical Facilities
- Utility Gas Stations
- Fuel Storage Areas
- Tank Farms
- Cargo Pump Rooms
- Hazardous Material Storage Facilities
- Industrial Manufacturing Plants
- Confined Space Monitoring
Features
- Fixed-point gas detection system
- Available for combustible gas, oxygen, and toxic gas monitoring
- Corrosion-resistant resin body construction
- Drip-proof design
- Built-in dimmer function
- Extension alarm contact (dry contact)
- Optional 4–20mA signal output
- Audible and visual alarm indication
- Suitable for industrial and marine applications
Benefits
- Provides early warning of hazardous gas conditions
- Improves personnel and asset safety
- Supports integration with alarm and control systems
- Durable construction for harsh environments
- Reliable long-term monitoring performance
- Low maintenance requirements
- Flexible installation options
- Suitable for new installations and retrofit projects
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