SLS 104 in Practice: The Next Step in Pantograph Charging
Since November 2025, the SLS 104 roof-mounted pantograph has been operating in regular service with Kölner Verkehrs-Betriebe (KVB). The real-world test highlights how pantograph charging systems are evolving—and what that means for day-to-day e-bus operations.

Seamless Transition—Immediate Impact
The switch from the SLS 102 to the SLS 104 was completed quickly and without any significant downtime and electrical or mechanical changes on the vehicle. For KVB, this meant no disruption to ongoing operations and a system that integrated directly into existing charging infrastructure.
The real difference, however, becomes clear in daily use.
SLS 104: What Changed in Operation
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SLS 104
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Integration
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Seamless transition with minimal effort
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Maintenance
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No maintenance during test period
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Maintenance intervals
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Significantly extended
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System uptime
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Continuous operation with zero failures
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Operational effort
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Noticeably reduced
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OEM Support
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No support needed during operation
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The key takeaway: These are not fundamental system changes, but targeted improvements that make a measurable difference in real-world operations.

Less Maintenance, Higher Uptime
In daily service, the SLS 104 delivered consistent performance. Throughout the entire test period, the system operated without failures — and without requiring any maintenance.
For transit operators, that translates directly into higher uptime, fewer service interruptions, and improved operational reliability.
In tightly scheduled e-bus networks, that level of stability is critical.
Reliable Performance in the Background
One of the most relevant advantages in practice: the system simply runs. The SLS 104 operated without maintenance throughout the test period, with no need for additional support from Schunk.
This reduces complexity for operators and frees up internal resources—an important factor as electric bus fleets continue to scale.
Clear Feedback from Operations
KVB’s assessment reflects this performance. Head of Vehicle Procurement Mr. Mujagic states:
“The test operation ran smoothly, and no maintenance was required. From our perspective, we would be very happy to keep the pantograph in operation. For us, the vehicle has already become an integral part of the operational fleet.”
A strong indication that the system has fully transitioned from testing into everyday use.
A Partnership That Drives Progress
Schunk and KVB have been working together for more than a decade. Pantographs and charging components from Schunk are already well established in Cologne’s network.
The SLS 104 builds on that foundation—refining an existing system rather than replacing it entirely.
Timo Staubach from Schunk Transit Systems adds:
“We are very satisfied with our partnership with Cologne and grateful for the open and straightforward collaboration throughout the test period. We’re especially pleased that the six-month evaluation was so positive and that the test has been extended based on these strong results.”
Extended Test Confirms Performance
After six months, the system underwent a scheduled evaluation—with clearly positive results. As a result, the test operation has been extended for another six months, again without maintenance.
This confirms both the robustness of the system and the progress compared to the previous generation.
Conclusion: Incremental Innovation, Real Operational Value
The SLS 104 demonstrates how incremental improvements in pantograph charging technology can deliver tangible benefits in e-bus operations.
Compared to the SLS 102, the improvements are clear: reduced maintenance, increased uptime, and a system that integrates seamlessly into daily operations.
For transit operators, that ultimately means lower operational complexity—and greater confidence in their charging infrastructure.
Interested in more information?
Here you can find all relevant brochures, technical documents, and product information about the Schunk SLS 104.
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Learn more about the Schunk SLS 104, its technical specifications, and real-world applications in high-power charging – on the product page with all the details about the solution.
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