Grounding Systems for Railways/Traction

Reliable shaft grounding, earthing contacts and CFG systems

Only with a perfectly matched grounding system are return, safety and signal currents safely and reliably discharged. It is therefore not without reason that grounding contacts can make a decisive contribution to the economical and safe operation of your rail vehicles. These grounding systems or grounding contacts are mounted either at the end of the axle (axial) or at the gearbox (radial). At Schunk, such solutions have been established for years and are part of a large repertoire.

Grounding systems must work reliably over as long a period as possible. At Schunk, you receive durable solutions for all common installation situations and interfaces. It is therefore no coincidence that leading vehicle manufacturers in the rail/traction sector rely on grounding systems from Schunk. Because with our technology, we have revolutionized the transmission of signal currents and ensured new dimensions in maintenance intervals.

Perfect protection with Schunk shaft grounding system “CFG”

Inverter-controlled drive systems generate currents that are small in magnitude, but at the same time have vagrant voltages. Over time, these vagrant voltages can wreak havoc in rail vehicle drive systems. Our shaft grounding system, called Carbon Fiber Grounding system (CFG system), reliably diverts vagabond shaft voltages to the vehicle ground. It thus reliably protects rolling bearings and adjacent assemblies in transmissions and engines from damage. The unique structure of interwoven carbon fibers ensures optimum contact and high abrasion resistance.

From all-carbon earthing contacts with optimal emergency running properties for currentless operation to systems for high current densities – from installation on the axle end or on the gearbox – all of our products stand out thanks to outstanding materials expertise, robust design, low wear and extremely long service lives. Our carbon brushes for earthing contacts are also available separately as spare parts.


CFG system prevents damages and reduces maintenance expenses

Vagabond shaft currents in converter-controlled AC motors cause bearing damage in motors and transmissions, produce high levels of noise, and result in greater heat production inside the affected roller bearings. Ultimately, all of these issues result expensive train downtimes. Our patented CFG systems are the right solution. They extend the service life and reliability of your trains by securely dissipating vagabond shaft currents. Our CFG systems can be adapted to the needs of the specific traction motor in the bogie. Thanks to their compact dimensions, they are also easy to retrofit. They also stand out for their resistance to heavy vibration and their ease of installation. We offer our patented solutions for installation on the transmission, engine, or according to customer-specific requirements.