Railway Signalling & Interlocking

6 Movable Track Elements 162 either AC or DC motors, with electrical supervision using mechanical contacts. The tooth gear transmission is designed to be not trailable with internal locking. EPM is designed to be installed on one side of the track. The movements of the throw bar for the fixed distance and confirmation that the detection bars are in this position are verified by the switching levers 5 and 9, and jointly with them connecting levers 4 and 11 (figure 6.15). When the throw bar is located in its end position, the roller of one of the switching levers sinks down into a notch of the collar 8 mounted upon the main drive shaft of the reduction gear. The checking scheme is commutated with the detection contacts 6, 10. These contacts are closed by the connecting levers. The closing is possible if Figure 6.15: Checking of point position in SP-6