Benjamin Brumec details how a collaborative approach enabled the design of a customised connectors solution
The Swiss Rhaetian Railway (RhB) transports thousands of people through the beautiful Swiss Alps, where climate conditions can be quite rough. To ensure comfort and security for the passengers, signals and data are sent through the complete train.
The Business Needs
RhB needed a new and highly stable system of electrical connectors between the train compositions to ensure that it signals can ﬂow reliably during the train rides. Surroundings in the Swiss Alps can be harsh with possible temperature variations of up to 60°C in a single ride. The new connection system had to feature 32 signal contacts and one data bus connector.
The customer wanted to replace three outdated systems with only one that was the most up-to-date technology and would work in very tight space conditions. The solution needed to be resistant to high temperature variations, vibrations and mechanical shocks, but also mud, break dust, wet with dew and salt spray. At that project phase, RhB had already decided on a particular connector, however, it wasn’t fully sufficient. Therefore, the new system had to ﬁt on this existing connection plate on the composition and was required to also resist hammer strokes in the event of icing.
In close cooperation with RhB, Stäubli Electrical Connectors helped to set up the technical speciﬁcations and then developed a completely new solution. The housing is very robust and provides a handle for easy opening. A sufficient overlap of the contact parts will ensure that even under severe vibration and temperature ﬂuctuations the contact is never interrupted. With a 15° departure angle of the plug to the vertical, mechanical stress of the cable is significantly reduced and the connector operation is extremely simpliﬁed. The construction of the cover lid prevents an accumulation of snow on the inside of the protective cover. The insertion of the connector is supported by two longitudinal pins, which means that the connector cannot tilt.
Based on the broad experience in railway technology there was a common understanding between RhB and Stäubli Electrical Connectors on how to approach the design of the new connection solution. The innovative product solution exceeded the customer expectations and even includes features that the customer had not thought of.
The robust handle simpliﬁes the operations and accelerates the composing of the wagons. The custom speciﬁc design and development integrating an existing connector saved conversion costs substantially. The special design with the two longitudinal pins prevents pins from being bent or knocked back and thus makes the connection very reliable and durable.
Stäubli Electrical Connectors faced the challenges very ﬂexibly and cooperatively. Due to the unique features of this solution also other Swiss railway operators rely on it. “The customised solutions developed for our application have been subjected to detailed testing by Stäubli Electrical Connectors, so that we can guarantee our customers maximum operational reliability,” confirms Leo Fäh, Rolling Stock Division, Head of Electrical Engineering at RhB.
Benjamin Brumec is with Stäubli