Berlin underground line 55, known as the "Kanzlerbahn", has operated for years on the section between Brandenburg Gate and Central Station. Following a comprehensive phase of planning and construction work lasting more than 10 years, in September 2020 the route extension to Alexanderplatz was completed and in the process line U55 was combined with the previous U5. The new U5 line now offers passengers the convenience of a direct journey from Hönow to Central Station without changes.
For the local tunnel systems, the Berliner Verkehrsbetriebe (Berlin Public Transport Services - BVG) imposed tightened safety conditions on the electrical engineering installed there, particularly in relation to technical fire safety. In the event of fire, the functionality of vital plant and systems had to be guaranteed.
The WKE cable junction boxes from Spelsberg with fuses integrated into the branch, meet these requirements. Thanks to these fuses, for the first time, nonreactive cable branching is possible since, in the event of a fault, the functional integrity in the main section is unaffected.
Thus, in the event of fire, operation of the electrical circuits for emergency lighting and other evacuation equipment is ensured for at least 30 minutes.
Spelsberg developed bespoke solutions to meet customer-specific requirements, with the WKE 300 and WKE 400 SL types, for challenging environments in the tunnels of the Berliner Verkehrsbetriebe. In a global innovation, the WKE 200 - 400 SL junction and connection boxes series combine in a single product the advantages of the screwless WAGO TOPJOB® S Push-in terminal blocks and certified functional integrity according to DIN 4102-12.
They therefore offer a safe solution wherever functional integrity, high vibration and impact resistance, and a reliable dust and water seal are required. Cooperative exchange of information, coupled with expert advice and project support from the Spelsberg team, enabled BVG to implement the necessary measures for safety of electrical installations in the event of fire in a fast and solution-oriented manner.