The EMTRAC system consists of three major components—vehicle components, wayside components (described on this page), and the software used to configure and monitor the system.

EMTRAC Wayside Equipment

Wayside equipment includes the cabinet-mounted Priority Detector (available in RF, optical, and universal RF/optical models), the pole-mounted Omni-Directional Antenna, and the optional Vehicle-Interrogator Kit, which automatically downloads activity logs and installs firmware updates as needed.

Priority Detector
EMTRAC TSP/EVP Priority Detector

EMTRAC ST-9283 Priority Detector

The EMTRAC Priority Detector enables secure vehicle-to-intersection (V2I) communication by utilizing a 900-MHz spread-spectrum transceiver and a single-board computer integrated in a dual-card assembly that plugs into the traffic cabinet’s detector rack or on an interior shelf. Priority Detectors are also capable of communication using NTCIP protocols.

The Priority Detector is compatible with NEMA, 170/2070, Caltrans, ITS, and custom cabinets. It support up to 16 inputs, allowing for priority calls to be received for multiple phases from EMTRAC Vehicle Computer Units.

The EMTRAC Omni-Directional Antennas provide 2.15 dBi gain performance. The antennas are ground-plane independent and can be mounted in a variety of locations. Antenna wiring is encapsulated to provide exceptional resistance to extreme weather conditions.

  • Includes serial RS-232 or Ethernet communications to enable remote monitoring of system activity and configuration of EMTRAC equipment through the existing traffic network
  • Supports up to 16 inputs and 16 outputs, with one auxiliary output configurable as a satellite timing signal
  • Logs up to 5,000 locally-stored events (up to 10,000 events with removable memory)
  • Four main directional outputs and up to 12 auxiliary outputs are provided, with each input and output signal optically isolated for 2,500 volts
  • Operates on 120 VAC with its own power supply, and fits NEMA, 170/2070, ITS, Caltrans, and custom cabinets
  • Includes indicator lights for power on, signal received, active-output by priority, and direction of signal or channel
  • Includes toggle switches to send output in either Priority 1 or Priority 2 mode, allowing manual testing of detector function and intersection response. The Standby/Active switch enables testing and configuration without affecting the live signal
  • Compatible with all major brands of NEMA and 170/2070 controllers
Vehicle Interrogator
EMTRAC Vehicle Interrogator Kit for TSP/EVP

EMTRAC Vehicle Interrogator Kit

The EMTRAC Interrogator System enables agencies to automatically transfer activity logs from EMTRAC-equipped vehicles and to upload firmware and database updates to these same onboard units.

As equipped vehicles return to the garage or station, the Vehicle Interrogator utilizes secure FHSS radio to download activity logs from onboard EMTRAC units. This data is forwarded to a server running EMTRAC Central Monitor, where it can be viewed by agency personnel.

The EMTRAC Vehicle Interrogator may be installed at bus garages, fire stations, rail operation Centers, municipal-vehicle garages and lots, as well as maintenance facilities.

  • Automatic Retrieval and Update: Wirelessly download activity logs from EMTRAC components, and automatically upload firmware or database updates to units that have not yet received the update.
  • Auto-Notifications: The EMTRAC software may be configured to email periodic activity logs to specified agency personnel.
  • System Monitoring: The EMTRAC software enables agency personnel to monitor connection status and history (between server and Interrogator as well as between Interrogator and EMTRAC components), and current RF signal strength.
  • Communication Stability: Data is not lost in cases of network interruption, and data transfers resume from the point of interruption.
  • Minimal Wired Connections: For external connections, the EMTRAC Interrogator Kit requires only 120 VAC power and Ethernet. All communication with EMTRAC vehicle components is performed wirelessly.
  • Limitless Memory: By transferring activity logs to the system server, onboard EMTRAC components are able to continually store new log entries.
  • Timeliness: High transfer rates enable data transfers that take a relatively short period of time, offering many options for where to mount the Interrogator—such as near refueling or washing stations.
  • Flexibility: The EMTRAC Interrogator may be mounted on wall, pole, or other structure, and multiple antenna options allow for reliable communication in even high-interference environments.
Auxiliary Terminal Board
EMTRAC Auxiliary Interface Panel

Auxiliary Terminal Board

The EMTRAC Auxiliary Terminal Board provides a simple way to connect a wide range of electrical signals to and from the Priority Detector within the traffic cabinet. The ST-9751 auxiliary board includes two terminal-block rows to accomodate both inputs and outputs. The terminal blocks accept wire leads which are secured with screw-connection tension sleeves. All output terminals are 24VDC NEMA logic.

Connections to the Priority Detector are made through the 26-pin D-Sub port. The Auxiliary Board Interface Cable connects the auxiliary board to the Priority Detector. Click here to open the auxiliary-board cut sheet.