Control Devices and Indicator Lights for Areas with Potentially Explosive Atmospheres

(24.06.2008) Elan, a subsidiary of the Schmersal Group, introduces a new range of control devices and indicator lights for the 22.3 mm industrial standard, which is suitable for use in potentially explosive dust and/or gas atmospheres.

The programme meets the requirements of the ATEX Directive 94/9/EC and can be used in much more fields than just the chemical industry, which is usually associated with the "explosion protection" subject. Not only gases, but all organic dusts and powders as well as wood powder and plastics are a major source of explosions when mixed with air. During food manufacturing processes, e.g. during the processing of flour or coffee, inflammable dust-air mixtures can occur as well. For these zones, the machine operator must execute a risk analysis in accordance with the ATEX Directive 1999/92/EC and implement appropriate explosion-preventing measures. One of these measures is, amongst others, the use of explosion-proof control devices and switchgear.

The entire Ex programme has a modular design. Each control device consists of contact elements, the mounting flange and the operating or display element. The modular design facilitates the assembly and allows a great diversity of variants: various versions of pushbuttons, illuminated buttons, indicator lights, emergency stop buttons, selector and key selector switches are available.

The switchgear is very easy to assemble. Well-tried and proven features and materials from the Elan control devices, such as metal front parts (selector switches) and high-quality shock-resistant thermoplastics (handles and transparent caps of the indicator lights and illuminated pushbuttons) have been retained in the R programme. The user therefore has a high-quality and durable series of switchgear for the man-machine interface at his disposal.

The front sealing of the devices meets the requirements for explosion protection and furthermore features a long lifetime, even in extreme ambient conditions, e.g. frequent contact with oils, organic and inorganic residues of grease, grinding dust and other pollutions.

The control devices can be installed in Ex Zones 1 and 2 (potentially explosive atmospheres due to the presence of gas) as well as Ex Zones 21 and 22 (potentially explosive atmospheres due to the presence of dust). As they all meet the requirements of the Ex standard EN 60079-0 with regard to shock resistance, they can be perfectly integrated in control panels and installation housings in potentially explosive atmospheres.

Schmersal Ltd
Sparrowhawk Close
Enigma Park
Tel - 01684 571980
Fax - 01684 560273

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