Overview
The Positive Train Control mandate presents an intricate and complex technical challenge involving a variety of situations that must be addressed in the field. Ansaldo STS USA has introduced a comprehensive series of products to allow our freight and commuter railroad customers to meet PTC requirements.
Products
MicroLok® II VitalNet CPU
Preserve your interlocking investment by upgrading your existing MicroLok® II system with a MicroLok® II VitalNet™ CPU (VitalNet CPU).
The VitalNet CPU provides a PTC ready interface for existing or new MicroLok II interlockings. Simply exchange your current CPU board with a VitalNet CPU board without affecting the MicroLok II logic. In most installations, only the PTC functionality must be tested. This eliminates the time and effort associated with a complete retest of the application logic.

VitalNet WIU 
The VitalNet WIU is a stand alone unit that vitally reports aspects to the onboard computer. It is a low input/output count device and is used to provide PTC compliance to relay locations, dark territory, hand throw switch monitoring and third party interlocking systems. It features:
- 6 vital inputs with fast detection, voltage or current
- 2 non-vital analog inputs for battery monitoring
- 3 vital outputs
- 3 Ethernet ports
- Fixed application
- Embedded web server for configuration and diagnostics
- Basic user interface functionality (status LED’s, inputs, communication, push button)
VitalNet Point Monitor
The VitalNet™ Point Monitor vitally monitors manually operated switches and connects to a VitalNet Wayside Interface Unit (WIU) to communicate a switch position in compliance with PTC regulations.
The sensor technology and custom point detector bar used in M23 Switch Machines has been modified to fit into a small, 4-inch tall point monitor casing that mounts directly onto the stock rail. The unit is reversible and can be set up for near or far point closed. The electronics continuously monitor the sensor's operation state and determines the switch point position. The point monitor provides indications for both normal and reverse.
VitalNet Wayside Messaging Server (WMS)
The VitalNet WMS is the perfect solution for wayside PTC communication. It provides IP switch/router functionality and interfaces with GPS information, as well as both both synchronous and asynchronous serial ports. The VitalNet WMS provides a certified hardware platform to run Interoperable Train Control Messaging (ITCM) software services.
VitalNet Current Sensor
The VitalNet Current Sensor combines the best current-sensing technology available into one device: a small, light package, diversity in detection and closed loop control capability. The unique form factor allows for installation in railroad applications without disarrangement, providing simple PTC installation on lamp signals.
The VitalNet Current Sensor is a prewired solution that features upper and lower current sensing tabs – in between are two current measuring elements. Each element is able to make individual measurements that the controller can compare for diversity. In combination with voltage detection, the current sensor allows for full vital signal detection.
Wayside Integrated Power System
Inside the Wayside Integrated Power System's bungalow, you can find everything needed to develop a system that meets PTC requirements for switch point monitoring in dark territory. The system is made up of several components, including:
- The power system - charges batteries that support all of the equipment
- The VitalNet Point Monitor - monitors the position of the switch point
- The VitalNew WIU or MicroLok II HB - processes and transmits device states to the VitalNet WMS
- The VitalNew WMS - communicates bungalow equipment status to "cloud" via cell network, as well as train control information to the Data Radio, which communicates to the railroad back office and/or locomotive.
VitalNet Office Safety Server
The VitalNet OSS encodes Mandatory Directives for delivery to the train's onboard computer and provides a vital computing platform that validates train authorities, speed restrictions, work authorities and dark territory switch positions. The vital protocol was developed to operate with conservative data radio bandwidth requirements. The flexible block design is scalable and allows the system’s configuration to accommodate future changes to the railroad.
MicroTrax® Track Circuit and Rail Integrity
A broken rail or undetected occupied block can be costly and potentially hazardous,
but leaving a track integrity system running in dark territory can be expensive as well. The MicroTrax® coded track circuit is a cost effective track integrity solution that is used in coordination with the MicroLok® II VitalNet™ CPU. The MicroTrax features efficient power consumption logic and the longest track circuit available (up to 27,000 feet). This means that the units are less expensive to run and fewer are needed to cover your track, resulting in significant cost savings.



