UK Clairair Miniature Infrared Methane Sensor - Cirius1

I. Cirius1 MiniatureInfrared Methane SensorWorking Description
The Cirius series sensors use non-dispersive infrared technology to detect the presence of gases. The sensor includes an infrared emitter, a dual infrared detector, and a unique optical waveguide that diffuses gas into it. The dual infrared detector responds to changes in incident light and acts on the sensor. The infrared source is pulsed with a 50% duty cycle, typically at a frequency between 2Hz and 4Hz. The sensor produces an active wavelength output; the measured gas changes the active wavelength, while the reference wavelength does not pass through the measured gas. These outputs contain a small AC signal consistent with the source pulse, superimposed on a DC blanking pulse level. The sensor provides internal temperature measurement via an embedded thermistor. The sensor requires power supply to the infrared detector and has external connections conforming to the industry standard 7-pin configuration.

To operate the sensor, it is necessary to incorporate a suitable power drive circuit and a circuit to extract the small AC signal from the DC blanking pulse level. This circuit amplifies the small AC signal, extracts a value, and processes the result to provide a linear output related to gas concentration. The sensor's temperature output is used for temperature compensation to achieve more comprehensive performance.

II. Cirius1 Miniature Infrared Methane Sensor Parameters and Features
• MEMS technology detector
• Detection range: 0-100% LFL methane, 0-100% LFL hydrocarbons, and 0-100% volume methane
• All-metal structure
• Patented sensor design
• Small internal volume
• Low power
• Active and reference signal outputs
• Embedded thermistor temperature sensor output
• Wide temperature range
• Fast response
• Poison-resistant
• Fail-safe operation
• Electrically isolated housing

III. Cirius1 Miniature Infrared Methane Sensor Performance
Power Consumption: Typically 150mW
Nominal Range: 0 - 5% volume methane, 0 - 100% LFL hydrocarbons, 0 - 100% volume methane
Max Time Without Failure: > 5 years
Weight: 17.6 grams
Vibration Resistance: Complies with EN61779-1
Relative Humidity: 0 - 95% RH non-condensing
Operating Temperature Range: -30°C ~ +75°C
Operating Pressure Range: 700 - 1300 hPa
Storage Temperature Range: -40°C ~ +80°C
Supply Voltage Range: 2.8V - 5.5V
Lamp Drive Voltage Range: 2.8V - 5.0V (50% duty cycle)