CGS500 Combustible Gas Detector features
• Temperature compensated
• Low drift
• Improved poison resistance
• Long life
• Fast response time
• Rugged stainless steel sensor
• Detects combustible gases and solvents
• Many accessories available
• Certified ATEX II 2 G EExd IIC T6
CGS500-IR Combustible Gas Detector features
• Temperature compensated
• Low drift
• Not affected by catalytic poisons
• Sensor MTBF of 10 years
• Fast response time
• Rugged stainless steel sensor
• Detects most hydrocarbons
• Many accessories available
• Certified ATEX II 2 G EExd IIC T6
CGS500 Combustible Gas Detector description
The CGS500 combustible gas sensor has been designed to measure concentrations of combustible gases in the range 0-100% LEL. The CGS500 is fitted in an EExe certified junction box.
Each sensor contains two thermocatalytic beads. Combustible gases will oxidise on the surface of the active bead while the reference bead compensates for changes in temperature, pressure etc. Each bead consists of a coil of fine platinum wire surrounded by an alumina based substrate containing a catalyst.
An electric current is passed through the bead which raises the temperature to a level where oxidation will occur. The catalyst reduces the temperature at which oxidation occurs, thus prolonging the life of the bead and resulting in much lower power consumption.
CGS500-IR Combustible Gas Detector description
The CGS500-IR sensor is a NDIR (non dispersive infrared) sensor designed to replace thermocatalytic gas sensors for monitoring hydrocarbon gases in the range 0-100% LEL. The CGS500-IR is available as a sensor only or fitted in an EEx e certified junction box.
The CGS500-IR uses advanced miniaturised NDIR technology combined with surface-mount microprocessor and firmware technology. A pulsed infrared source emits a broad spectrum infrared beam within an optical cavity. The system measures the adsorption of infrared energy as it passes through a gas sample. Different gases have clearly defined absorption characteristics, their concentration can be determined by their absorption of infrared radiation at the wavelength determined by filter lambda 1 in the diagram.
To compensate for interfering factors filter lambda 2 isolates another wavelength which is used to measure the total transmission through the optical cavity and is not affected by the gas being monitored. By comparing the infrared energy reaching each of the two detectors, the concentration of the gas sample can be determined. The signal processor compares and linearises these two signals. A thermistor monitors the sensor temperature and the signal processor factors in variations caused by temperature changes.
| CGS500 Specifications | |
| Operating Voltage | 2.05V |
| Operating Current | 300mA |
| Detection Range | 0-100% LEL |
| T90 Response Time | Typically <15 seconds |
| Stabilisation Time | 1 minute |
| Preconditioning Time | 1 Hour |
| Operating Temperature Range | -40°C to +40°C |
| Mounting Thread | M25 X 1.5mm |
| Accessory Thread | M42 X 1.5mm |
| Weight | 750g (junction box and sensor) |
| Size of junction box (excluding sensor) | 75mm X 80mm X 58mm |
| Electromagnetic Conformance (EMC) | Complies with EN50081 and EN50082 |
| ATEX certification | EExd IIC T6 (Certificate No. BAS00ATEX2246X) |
| Wiring details | Available accessories with M42 thread | ||
| Red wire | Active bead | Splashguard | C13038 |
| Grey wire | Junction | Flow adapter | C13055 |
| Black wire | Reference bead | Gas applicator | C13063 |
| Filter adapter | C13113 | ||
| Collecting cone | C13089 | ||
