03-09-2016, 08:10 PM
OCS (catenary) tensioners have been installed on either side of Columbia! 2 on the North side, 2 on the South. This is where one line stops, and another begins. These tensioners function by using a large, cylindrical weight hanging from a rope which is fixed to the larger diameter on that big pulley. The smaller diameter has another rope wound around it - giving a huge mechanical advantage. A little big of weight gets a lot of pulling force. This is what keeps the overhead line tight.