Rail Line project France: the droppers

Case Study

Innovative Connection Droppers

When an international rail player needs connectivity solutions ensuring good mechanical and electrical performances to warranty the reliability and speed of railway lines, TE supported them in designing a tailor made droppers and specific tool to ease the installation.

The Challenge

Increase overall railway system performance

The French National Railway company (SNCF) is a pioner in development and construction of high speed railway lines since 1981. 

Droppers have a fundamental role in the overall railway system performance since they are key connectors of the catenary. 

The droppers used by SNCF  were articulated at upper and lower parts, they had a good mechanical behaviour but the articulations led to poor electrical performance of the droppres. To overcome this loss of electrical contact between the messenger and the contact wire a distribution connection was installed every 200 meters (maxiumu).  The extra weight of the distribution connection could locally bend the contact wire which limited the speed of the train.

SNCF was looking for droppers ensuring good mechanical behaviour while providing high electrical performance in order to improve the reliability and the speed of railway lines.


The Solution

Customized droppers

SNCF and TE engineering teams worked together to an innovative solution that would insure high mechanical behaviour without lower the electrical performance. 

They designed a dropper that provides two mechanical and electrical functions without any screw or bolt. 

In order to warranty high mechanical behaviour the dropper is still articulated at the upper and lower sides. Nevertheless a binding cable has been added at both sides to make sure to consistently maintain an electrical contact between messenger and contact wires. 


TE also developped a specific tool named SIMAGRIF to ease the installation of the new innovative dropper. 

"TE demonstrated their strength in an uncommon context. They clearly positionned themselves as a key railway supplier thanks to an innovative solution."


Numbers of parts already in service


Year of the official approval of TE's droppers by SNCF


Numbers of droppers that have been installed between 2014 and 2016.

The Outcome

Tailor made solutions

As a worlwide pioneer in development and construction of high speed railway lines, SNCF needed to insure the reliability and the speed of railway lines.

With decades of expertise and experience in designing and supplying products for demanding rail applications, TE Connectivity worked on thinking, testing and manufacturing this new dropper along with this new tool. 


TE's Simel droppers have been installed on field for more than 20 years and are still offering high performances.