Surge protective device for linear direct current systems

Surge protection for direct current

Due to their structure, direct current systems exhibit a different behavior during regular operation and in the event of an error than alternating current systems. Consequently, they require specific surge protective devices. Depending on the installation location and requirements, these SPDs are subdivided into type 1 and type 2 protective devices.

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Your advantages

  • Safe operation of DC voltage supply systems thanks to reliable protection against surge voltages
  • Highly versatile with a maximum altitude of up to 6,000 m (above mean sea level)
  • Space-saving installation due to the compact design
  • Excellent level of information provided by mechanical/visual status indicator and remote indication contact
Surge protective device for nominal voltages up to 1,000 V DC, with adapted insertion funnels

Surge protective device for DC applications with nominal voltages up to 1,000 V DC

Requirements for surge protection

Surge protective devices for protecting DC applications must be adapted to what are in some cases much more stringent requirements. For use in DC systems with particularly high voltage, an SPD must be designed for up to 1,100 V continuous voltage. This is associated with much more stringent requirements for air clearances and creepage distances, which prevent sparkover between the connection terminal blocks and the conductors connected in them. For DC systems with smaller voltages, the requirements are not quite as stringent. However, here too the clear recommendation is to always select the surge protection for the appropriate voltage.

Fundamental advantages of alternating current and direct current

Alternating current or AC voltage offers two major advantages: It can be easily transformed and switched. During transport, however, reactive power is always transmitted as well, which leads to corresponding transmission losses.

Direct current or DC voltage offers the advantage that the desired voltages are used directly at the corresponding systems, machines, and devices via more efficient DC/DC or DC/AC converters. Complex DC intermediate circuits with AC/DC conversion in frequency converters are no longer necessary. In addition, no reactive power is transported in DC transmission systems. This significantly reduces energy losses during transport.

Typical fields of application DC applications can be found, for example, in the following industries and applications

Cell towers against a blue sky
Server cabinets of a data center
Data centers
Production hall with conveyor belts and machines
Industrial DC applications
Person charging an electric vehicle at a futuristic charging park
Battery storage system container in a meadow with photovoltaics and wind power in the background
Battery storage systems
View over the roof of a production hall with installed photovoltaic panels