DEHN protects the industry
DEHN protects the industry

DEHNguard SE CI 440 - for main voltages up to 400/690 V

With integrated backup fuse!

In the type 2 surge arrester DEHNguard SE CI overvoltage protection and backup fuse are combined in a single device. An enormous benefit considering the dimensioning of the switchgear cabinet and in case of retrofitting. Thus, safety can be increased and costs can be saved.

Choose the appropriate arrester for your application


For the industry:


With a rated voltage of 400/690 V it is ideally suited for systems which rely on a constant current supply and therefore use the IT network. Therefore, the arrester is especially interesting for application in hospitals, computer centres and airports.


For wind turbines:


Especially for use in wind turbines. An unintended response of the arrester in case of voltage peaks is avoided. Thus, the arrester is saved and its service life increased.


Your benefits

With an integrated backup fuse, the benefits are obvious:

  • Shorter planning time
    Choosing the right backup fuse, calculating the down conductors, creating and labelling drawings – planning time which you can save.
  • Saves material
    Fuse base, fuse links, connecting cables – no longer necessary. So, you reduce the material costs.
  • Shorter installation time
    Unpacking, preparing, cutting to length, stripping and clamping – not necessary anymore either. This saves man-hours.
  • Simplified insulation test
    Replace the protection module quickly and easily without tools. A genuine advantage with regard to the installation time. The modular system also saves a lot of time when it comes to the regular insulation tests.
  • Increased installation safety
    It is easy to make a mistake when selecting the fuse – production downtimes or system failure is the worst case scenario. With the decision for the complete unit you are on the safe side and your employees more relaxed.

Expert information

Rapid diagnosis by remote monitoring

By coupling with the remote signalling contact, the internal fuse is automatically monitored. This keeps you informed about the state of both arrester and fuse in real time.

Easy installation

According to the installation standard, the maximum cable length is limited to 0.5 metres. Wiring an external back-up fuse already uses up a considerable portion of this length, significantly restricting your installation possibilities. With CI arresters, you stay flexible and can easily meet the requirements of the standard.

More safety due to lower protection level

The protection level specified applies to the surge protective device itself. If an external backup fuse is added, the protection level changes for the worse. DG SE CI (WE) 440 FM, in contrast, has the value of 2 kV as a complete unit which, for you, means that nothing is lost here!


Have you got any questions? Contact us.

Technical support

Phone: +49 9181 906 1750

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