August 16, 2016 - The Ex 97 switching devices with plastic housings, are tested and certified according to ATEX and IECEx for use in Gas Ex zones 1 and 2, as well as dust Ex zones 21 and 22. They can also be used in temperatures down to -60°C, which is a terribly demanding, most particularly for the construction and sealing of the housings.
In addition, the housing covers are completely vulcanised, guaranteeing that they remain sealed even upon impact. To seal the plungers, the steute developers have implemented a redundant sealing system comprising an external sealing cuff suitable for low temperatures and an internal Teflon sealing ring.
The sealing materials used have been classified by their own manufacturers for temperatures down to -95°C, and the lubricants used for temperatures down to -75°C. There is thus sufficient "safety clearance" before the -60°C certified for the Ex 97 switches is reached. This means that users, e.g. in the offshore oil and gas industry, can be certain that the new position switches will work reliably even in their truly extreme environments.
Due to their comprehensive range of actuators (plungers, roller levers, turning levers, push buttons) and compact dimensions, the Ex norm switches, available as snap action or slow action, are very versatile and can easily be integrated in an existing construction. Their protectively insulated plastic design also makes earthing and potential equalisation unnecessary.
