Gas detection upgrades with infra-red

17 November 2008

The intrinsically safe detection of toxic gases and vapours is necessary for the protection of staff and assets. Draeger Gas Detection division has upgraded to infra-red technology with the explosion-proof DraegerSensor IR. Designed to detect flammable gases and vapours, the ATEX approved DraegerSensor IR has been specifically developed to allow existing pellistors or catalytic bead sensors to be replaced easily, without creating technical problems.

Even in the harshest of conditions, these poison resistant, fail-safe sensors are simple to install, simply unscrew the traditional pellistor and screw in the innovative DraegerSensor IR.

The inclusion of a Wheatstone Bridge, which is able to duplicate a standard pellistor output, also means that existing cables and control devices, regardless of manufacturer, can still be used.

Requiring no adaptation to either the control system or the electrical wiring, the DraegerSensor IR features 3-wire connection which eliminates the need for extra cabling. In addition, because of the availability of metric M25 as well as ¾ NPT thread with the new sensor, it can even be used with existing junction boxes.
Featuring an expected lifespan of more than 15 years and benefiting from significantly reduced maintenance costs, the Sensor is protected by a robust stainless steel enclosure and provides high reliability as well as excellent measurement performance. This is particularly true where fast response and long-term stability are concerned.

Measuring 0 to 100 %LEL (lower explosive limit) for methane, propane and ethylene, it has a typical response time of less than 30 seconds, complete with IP67 rated splash guard and calibration adapter. Able to operate in temperature ranges from –40 to +65 degrees C, it also incorporates heated optics and can be operated in humid environments from 0 to 100 % RH (relative humidity).

For optimum flexibility, each of the three gases is listed in one internal gas library and the target gas can be changed, at any time, via a magnetic wand. For maximum reliability, individual linearisation curves also offer temperature-compensated readings.

Meeting the requirements of ATEX, IECEx, UL and CSA, the DraegerSensor IR can be supplied with a wide variety of options for special applications with advanced requirements. These include a calibration adapter, process adapter and duct mount set.

In addition to infra-red techniques, Draeger has also launched the Polytron 7000, believed to be the first ever gas detector to meet the needs of all toxic and oxygen requirements from a single platform.
The Polytron 7000 has been developed in conjunction with Draeger customers to provide a fast, straightforward solution to the constantly changing requirements of toxic gas and oxygen measurement in both new and existing installations, the system is both modular in concept and versatile in use.

Featuring a host of optional system functionalities that can be mixed and matched to suit different applications, the Polytron 7000 can be upgraded as and when required. Offering 4 to 20ma and HART fieldbus capabilities as well as sensor self-checking and data/event logging software, the system can also provide pump, relay and remote sensor modules. In addition, it is compatible with the PDA m515-Ex which can be used to configure the transmitter, transfer concentration data to a PC, or to copy one configuration to another transmitter.

A simple three-button navigation intuitively guides the user through the menu driven functions and a large graphic display incorporates descriptive icons as well as plain text information to help with any diagnosis of the gas detector.

Designed to bring the maximum level of operational choice to the user, the system also utilises the Polytron Docking Station technology, which minimises system downtime and simplifies maintenance.

The Polytron docking station can be pre-installed on walls and pipes without special mounting plates and, at commissioning, can be easily connected to the transmitter by a quick-lock mechanism.

Enabling the fast removal and replacement of “like-for-like” sensors that are equipped with a data memory storing calibration information, the Polytron 7000 is also designed to accept a pre-calibrated sensor under the cost effective Draeger Sensor Exchange Programme.

Ensuring optimum performance and reliability, the system is fully compatible with the new electrochemical DraegerSensor range. Designed for use 24 hours a day, 365 days a year in the toughest environments, DraegerSensors combine high sensitivity and long term stability with extended sensor longevity.
DraegerSensors feature an embedded data memory that stores all sensor specific data such as gas, sensitivity, self-test parameters, predictive maintenance functions, sensor vitality, temperature compensation data, cross-sensitivity data and calibration information.

As the data is stored in the sensor and not in the transmitter, this means that calibration can be carried out anywhere and at any time. Eliminating the need for onsite calibration, this also means that as soon as the sensor is plugged into the transmitter, all necessary information is downloaded to the transmitter without the necessity of any further adjustments.

Fully certified to ATEX II 1G Eex ia IIC T4/6 and II 3G Eex ia IIC T6, the Polytron 7000 conforms to IP67 as standard.

Draeger Gas Detection division offers products, services and system solutions for all encompassing toxic, flammable and oxygen detection, flame detection and design, build, commission and maintenance of fire and gas detection systems for protection of personnel and assets.