The coordinated type 1 DEHNbloc® Maxi 1 CI 440 FM and DEHNbloc Maxi® 1 CI 760 FM surge protective devices (SPD) are specifically designed for higher system voltages, thus ensuring efficient protection against direct and indirect lightning currents in various industrial applications. The devices require up to 60 % less space than a conventional solution with external backup fuse. In addition, the user does not have to care about the correct dimensioning of the backup fuse since it is already integrated in the device and thus adapted to the performance parameters of the surge protection components of the type 1 SPD. The new surge protection devices DEHNbloc® Maxi 1 CI 440 FM and DEHNbloc® Maxi 1 CI 760 FM will ideally complement the protection devices with integrated fuse of DEHN, which are already successfully placed on the market for several years.
This product solution is a type 1 lightning current arrester with an arrester backup fuse integrated in the surge protective device (SPD). This impulse-current-resistant fuse is optimised for discharging lightning currents of 10/350 µs wave form. To this end, a spark gap is used which has a high mains follow current extinguishing capability in case of higher system voltages up to 760 V a.c. Thus, power-frequency follow currents are significantly limited and extinguished within a few milliseconds.
The operating-current-free status / fault indication of DEHNbloc® Maxi 1 CI also monitors the integrated backup fuse and indicates its status. In addition to the standard visual indication with green and red indicator flags, the device features a three-pole remote signalling terminal. With its floating changeover contact, the remote signalling contact can be used as a break or make contact according to the particular circuit concept.
The devices require up to 60 % less space in the distribution board than a conventional solution with external backup fuse. In addition, the user does not have to care about the correct dimensioning of the backup fuse since it is already integrated in the device and thus adapted to the performance parameters of the surge protection components of the type 1 SPD.
The normative requirement (IEC 60364-5-53) that the total length of the connecting cables of an SPD must not exceed 1 m can be easily fulfilled since the connecting cable lengths for the fuse and the length of the fuse itself are eliminated since the fuse is integrated in the arrester.
To sum up, DEHNbloc® Maxi 1 CI 440 FM and DEHNbloc® Maxi 1 CI 760 FM provide the following benefits:
- Significant space savings compared to conventional solutions with separate SPD and backup fuse
- Considerably reduced installation effort at lower installation costs
- Integrated fuse monitoring and remote signalling
