The Switch Point Protection System (SPP) is used as an interlock device to prevent a track switch from activating when a train is within the zone surrounding the switch.
The system is used in yards where remote control of the switch is performed from a Central control room, where the operator may not have full visibility of the track switch. The SPP system assures that a derailment will not occur due to switching when a train is running over the system.
An axle counter is placed at each of the 3 ports of the switch. A SilverHawk controller is used to read the axle counters and perform the software functions.
The SPP system is a Function Block Application pre-loaded into the SilverHawk controller. Source code is provided so users can tune the operation if needed.