Mid Point Anchor

With Automatic Tensioned equipment the contact wire is held level by the weights either end. The contact wire could move towards one end or the other. This would cause a twist at the registration points. The drag on the contact wire by the locomotive or units pantograph tries to push the wire towards one end. To prevent this the catenary wire is anchored in the centre of the wire run. If you have more than 14 masts on you layout and do not want to have an overlap then an anchor point is ideal.

 

On Mk1 one equipment it is a portal mast for both twin track and multiple tracks. In some locations it is a lattice mast normally lightweight construction but sometimes a medium weight and in other places a girder frame is used. Oddly for some reason many of the stations on the LTSR have an anchor point half way down their platforms.

 

Mk111 equipment has two differing types of anchor. Twin track uses three special masts. The two outer ones have a tie wire and a fasting point for the anchor wires. These anchor wires hold the modified cantilever arm in position longitudinally to the track. The special cantilever arm has with an apparatus that holds the catenary wire in place as well as fixing points for the anchor wires.

 

With headspan the mast in the centre has fixing points for the catenary wire on the top cross-span wire. On two masts either side of the anchor the catenary wire is held in place in a clamp on the support arm rather than running over a pulley.