The gas transmitter ADOS GTR 196 is suitable for continuous measurement of gases in normal areas and areas where there is a risk of explosion.
By employing 5 different types of sensor, noxious, explosive and non-combustible gases and vapours can be measured.
A current signal is generated that is proportional to the measured concentration of gas, which is transmitted to an evaluation unit placed in a safe area, away from any dangers of explosion.
The type test of the explosion-protected gas transmitter, is completed by the KEMA.
TGS sensor
The TGS sensor contains a semiconductor sensor, which is constructed on SnO2-sintered N-substrate. When combustible or reducing gases are absorbed by the surface of the sensor, the concentration of the test gas is determined by the change in conductivity.
VQ sensor
The head of the VQ sensor functions on the principle of heat reaction. When combustible or reducing gases or vapours come in contact with the measuring element, they are subjected to catalytic combustion, which causes a rise in temperature; this rise causes a change in the resistance of the measuring element which is used as a measure of the component of gas being tested.
The inert element is for compensating the temperature and conductivity of the test gas.
GOW sensor
The GOW sensor functions on the principle of thermal conductivity. Two rhenium-tungsten resistors are used as a measuring element, where the comparison element is subjected to normal ambient air and the measuring element is subjected to the test gas. Any change in the concentration of gas at the measurement element causes a change in temperature, which is due to the variation of conductivity.
The resultant change in resistance is a direct measure of the gas concentration.
TOX sensor
The TOX sensor is a measurement system with an electro-chemical cell, where the sampled gas is measured by diffusion. In the case of oxygen measurement the oxygen content is reduced in an electrolyte, thus producing a small flow of current (electro-chemical process). At a constant air pressure, this current is directly proportional to the oxygen concentration in the sampled air.
The IR sensor
The test gas flows through a measurement chamber that incorporates an IR radiating source and a two-channel infrared detector. The intensity of the infrared radiation is reduced as it passes through the gas molecules. The concentration of the gas can then be calculated by the magnitude of the reduction in intensity. Since only absorption of the wavelength (A) specific to the gas under test in relation to the wavelength (B) not absorbed by a test gas is considered, interference due to dust, ageing etc., is almost fully compensated.
Chemical industry
Manufacture of paints and varnishes
Plastics processing plants
Sewage works
Gas-fired boiler systems
Liquid gas storage houses
Laboratories
Oxygen concentration measurements
Refineries
Cold storage houses (Ammonia monitoring)
Paint spraying booths
and many more.
| Type | TGS | VQ | GOW |
| Measurement method | Semiconductor | Heat reduction | Thermal conductivity |
| Measurement range | ppm ranges to 100 % LEL | ppm ranges to 100 % LEL | from 0-5 Vol % to 0-100 Vol % |
| Percentage error of f.s.d. | ±5 % | ±3 % | ±5 % |
| Temperature range | -25 °C to +55 °C | -25 °C to +55 °C | -25 °C to +55 °C |
| Temperature effect | 3 % | 2 % | 3 % |
| Response time (t90) | approx. 55 sec. | approx. 40 sec. | approx. 55 sec. |
| Pressure effect (atm.) | 1 % | 1 % | 1 % |
| Mounting position | optional | optional | optional |
| Application | Poisonous, combustible and explosive gases in the LEL region | Poisonous, combustible and explosive gases in the LEL region | Gases exhibiting substantial differences in thermal conductivity, compared to air |
| Versions available | industrial (Al), industrial (VA)- and Ex-version | industrial (Al), industrial (VA)- and Ex-version | industrial (Al), industrial (VA)- and Ex-version |
| Service life of the sensor | unlimited, when used for gases not causing catalytic poisoning | unlimited, when used for gases not causing catalytic poisoning | unlimited, when used with gases that do not attack aluminium, rhenium-tungsten or gold |
| Supply voltage | 15 – 30 V | 15 – 30 V | 15 – 30 V |
| Interfaces | 3-wire techniques 4-20 mA or LON? 4-wire techniques, galvanically isolated, data transfer 78 kB/s | 3-wire techniques 4-20 mA or LON? 4-wire techniques, galvanically isolated, data transfer 78 kB/s | 3-wire techniques 4-20 mA or LON? 4-wire techniques, galvanically isolated, data transfer 78 kB/s |
| Protection | II 2 G Ex demb [ia] IIC T | II 2 G Ex demb [ia] IIC T6 | II 2 G Ex demb [ia] IIC T6 |
| Ex-Version | KEMA 03 ATEX 2403 X | KEMA 03 ATEX 2403 X | KEMA 03 ATEX 2403 X |
| Protection class | IP 54 | IP 54 | IP 54 |
Dimensions | 150 x 170 x 105 mm | 150 x 170 x 105 mm | 150 x 170 x 105 mm |
| Weight | 2,7 kg | 2,7 kg | 2,7 kg |
| Type | TOX | IR | PID |
| Measurement method | Electro-chemical cell | Infrared | Photo-Ionisation |
| Measurement range | ppm ranges to 100 LEL % | 0–100 % LEL CH4, C3H8, C2H2, 0–100 Vol % CH4 0–1, 2, 3, 4, 5 Vol % CO2 | 0 – 200 ppm to 0 – 2.000 ppm |
| Percentage error of f.s.d. | ± 3% | ± 2 % | ± 5 % |
| Temperature range | -25 °C to +55 °C | -25 °C to +55 °C | -25 °C to +55 °C |
| Temperature effect | 2 % | 2 % | 3 % |
| Response time (t90) | approx. 60 sec. | approx. 45 sec. | approx. 120 sec. |
| Pressure effect (atm.) | 1 % | 4 % | 1 % |
| Mounting position | optional | optional | optional |
| Application | O2, CO, NH3, NO2,SO2, H2S a.o. | CH4 (Vol %; LEL) Propane (LEL) CO2 (Vol %) | e.g. C7H8, C8H10 CHCl3, PH3 |
| Versions available | industrial (Al),industrial (VA)- and Ex-version | industrial (Al),industrial (VA)- and Ex-version | industrial (Al),industrial (VA)- and Ex-version |
| Service life of the sensor | 12 months to 5 years depending on the measuring cell | approx. 5 years | 12 monthss |
| Supply voltage | 15 – 30 V | 15 – 30 V | 15 – 30 V |
| Interfaces | 3-wire techniques 4-20 mA or LON? 4-wire techniques, galvanically isolated, data transfer 78 kB/s | 3-wire techniques 4-20 mA or LON? 4-wire techniques, galvanically isolated, data transfer 78 kB/s | 3-wire techniques 4-20 mA or LON? 4-wire techniques, galvanically isolated, data transfer 78 kB/s |
| Protection | II 2 G Ex demb [ia] IIC T | II 2 G Ex demb [ia] IIC T6 | II 2 G Ex demb [ia] IIC T6 |
| Ex-Version | KEMA 03 ATEX 2403 | KEMA 03 ATEX 2403 X | KEMA 03 ATEX 2403 X |
| Protection class | IP 54 | IP 54 | IP 54 |
| Dimensions (WxHxD) | 100 x 180 x 80 mm | 100 x 180 x 80 mm | 100 x 180 x 80 mm |
| Weight | 1,1 kg | 1,1 kg | 1,1 kg |
