Due to the elongation of the contact and messenger wires caused by the variation in atmospheric temperature, the mechanical tension systems are defined by the compensation ratio, in 1/3, 1/4 or 1/5, and the type of system, whether it is concentric pulleys, several pulley system, or spring. ARCA offers the aforementioned types of mechanical compensation and according to the different characteristics in each case (such as: with or without brake or the structure for supporting and guiding the counterweights):

• Concentric toothed pulleys with counterweight fall arrest system in case of cable failure/cutting on the line.
• Several pulley system
• Spring tensioner according to the characteristics of the section to be compensated and the mechanical tension of the cables.