SI-100 is a IEC Ex fixed gas detector installed in a place where potential gas hazard occurs to measure oxygen, toxic gas and combustible gas. It shows not only the concentration of gas but also diagnostic result of the unit itself through the LCD display and can be connected to the controller with a standard 4-20mA analog output communication or RS-485 digital communication.

IECEx Approved

  • SI-100 measures the concentration of the flammable gas, toxic gas, oxygen and display with LCD
  • Easy magnetic bar operation
  • Big digital LCD installed with a blue backlight
  • Explosive proof structure
  • IP65: Water and dust resistant structure
  • Simple push button gas calibration
  • RUSSIA Gost-R Certification
  • EUROPE electromagnetic waves fitness Certification
  • Australian Certificate of Calibration

Locally Technically Supported by Gas Detection Australia

Related Products

Sewage Treatment Plant Monitoring

The presence of Hydrogen Sulphide  can be detected by using the Gas Detection Australia GDA 2529 gas sensor to detect leaks of Hydrogen Sulphide  and evoke deodorisation plant. The SI-100C gas sensor can be used to monitor for leaks of LEL levels of methane gas. In digester applications Carbon dioxide can be detected using the GDA 4350  

Designed, Manufactured and Supported in Australia.

Battery Room Monitoring

The SI-100C and a range of associated Gas Detection Australia controllers can be used in battery room gas detection  to detect hydrogen in battery rooms and sound alarms. The battery room gas detection systems comprise of a hydrogen gas sensor SI-100C and a gas sensor control unit. The Gas Detection Australia control unit  GDA 4020 or GDA 4011 is situated external to the battery room to display the gas concentrations and the alarm status. The battery room gas detection system can then be interfaced to extraction fans, sounders or other apparatus. For smaller battery charging rooms the standalone GDA 40126 can provide an integrated sensor and controller with outputs to drive extraction fans and sounders.

Designed, Manufactured and Supported in Australia.

Hazardous Areas (IEC Ex Certified)

IEC Ex approved gas detectors / gas sensors for use in Zone 1 areas within Australia for both Toxic and Flammable gas


Specification NameSpecification Value
Detectable GasesSee Ordering Information for the full list of gas types and specifications
Accuracy of Reading±3% / Full scale
Operation mode displayDigital LCD display, LCD Backlight, 4 Indicator LED
Measuring value displayDigital LCD Display(4-digit)
Parameter controlFront 3 magnetic switch (calibration, maintenance, alarm setting)
Power Requirements10~30 VDC
Power Consumption600 mA
Output TypesAnalog: 4-20mA, Digital: RS-485 (Option)
Connection3 way plug connector
WiringPower + Signal cable : 3-wire 1.5sq (AWG16) / 2,500m max
Conduit connectionNPT 3/4" (2way)
Alarm StagesAlarm value(1,2,3 alarm) | Alarm time (instant&delay) 1~30min | Alarm dead band | Relay output on/off
Operating Temperature-20℃ ~ 50℃
Operating Humidity5% to 95% RH(Non-condensing)
Enclosure MaterialAluminium, Stainless steel(STS304)
Dimensions150(W) × 165(H) × 110(D)mm
ApprovalEx d IIC T5 (IECEx)
Enclosure RatingIP65

 SENKO SI-100 Fixed Gas Detector

  • SI-100 Fixed Gas Detector
  • Calibration Cap
  • User Manual
  • Calibration Certificate
Part Number Gas Sensor Technology Range Resolution Sensor life time
SI-100-001 Oxygen (O₂) Electrochemical 0-30% Vol 0.1% Vol > 18 Months
SI-100-002 Carbon Monoxide (CO) Electrochemical 0-500 ppm 1 ppm > 2 Years
SI-100-003 Sulfur Dioxide (SO₂) Electrochemical 0-20 ppm 0.1 ppm > 2 Years
SI-100-004 Hydrogen (H₂) Catalytic 0-100% LEL 1% LEL > 5 Years
SI-100-005 Hydrogen (H₂) Electrochemical 0-1000 ppm Within 5 ppm > 2 Years
SI-100-006 Hydrogen Sulfide (H₂S) Electrochemical 0-100 ppm 1 ppm > 2 Years
SI-100-007 Hydrogen Sulfide (H₂S) PID 0-50 ppm 0.1 ppm > 2 Years
SI-100-008 Hydrogen Peroxide (H₂O₂) Electrochemical 0~10ppm 0.1ppm > 2 Years
SI-100-009 Combustible Catalytic 0-100% LEL 1% LEL > 5 Years
SI-100-010 Combustible IR 0-100% LEL 1% LEL > 2 Years
SI-100-011 Ammonia (NH₃) Electrochemical 0-100 ppm 1 ppm > 2 Years
SI-100-012 Acetylene (C₂H₂) Catalytic 0-100% LEL 1% LEL > 5 Years
SI-100-013 Ethanol (C6H5OH) Catalytic 0-100% LEL 1% LEL > 5 Years
SI-100-014 Ethylene (C₂H4) Catalytic 0~100%LEL 1% LEL > 5 Years
SI-100-015 Ethylene Oxide (C2H4O) IR 0-100% LEL 1% LEL > 2 Years
SI-100-016 Ethylene Oxide (C2H4O) Electrochemical 0~30 ppm 0.1 ppm > 2 Years
SI-100-017 Toluene (C6H5CH3) IR 0-100% LEL 1% LEL > 2 Years
SI-100-018 Toluene (C6H5CH3) Catalytic 0-100% LEL 1% LEL > 5 Years
SI-100-019 Acetic Acid (CH3COOH) Catalytic 0-100% LEL 1% LEL > 5 Years
SI-100-020 Methane (CH4) IR 0-9999 ppm Within 20 ppm > 2 years
SI-100-021 Methane (CH4) IR 0-100% LEL 1% LEL > 2 years
SI-100-022 Methane (CH4) IR 0-100% Vol 1% Vol > 2 years
SI-100-023 Methanol (CH3OH) Catalytic 0-100% LEL 1% LEL > 5 Years
SI-100-024 Chlorine (CL₂) Electrochemical 0-5 ppm 0.1 ppm > 2 Years
SI-100-025 Chlorine (CL₂) Electrochemical 0-20 ppm 0.1 ppm > 2 Years
SI-100-026 Carbon Dioxide (CO₂) IR 0-2000 ppm Within 3 ppm > 2 Years
SI-100-027 Carbon Dioxide (CO₂) IR 0-5000 ppm Within 3 ppm > 2 Years
SI-100-028 Carbon Dioxide (CO₂) IR 0-5% Vol 0.1% Vol > 2 Years
SI-100-029 Hydrogen Chloride (HCI) Electrochemical 0-10 ppm 0.1 ppm > 2 Years
SI-100-030 Volatile Organic Compound (VOC) PID 0-1000 ppm Within 3 ppm > 2 Years
SI-100-031 Xylene (C8H10) IR 0-100% LEL 1% LEL > 2 Years
SI-100-032 Nitrogen Monoxide (NO) Electrochemical 0~100ppm 1ppm > 2 Years
SI-100-033 Nitrogen Dioxide (NO₂) Electrochemical 0~20ppm 0.1ppm > 2 Years



Part Number Image Description
SI-100-### S SI-100

SI-100-### Replacement Sensor Head

SI-100 Magnetic Bar   Magnetic bar for controlling SI-100 Units
SI-100 Filter   Replacement sintered metal filter
SI-100 Plug   PT 3/4
SI-100 Calibration Cap   Calibration Cap for SI-100 & SI-100C



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IECEx Approved

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IECEx Approved