Substation Gateway

Substation Gateways for Protocol Conversion

Distribution System Operators (DSO) typically use a variety of outstation devices, master systems and protocols. Each new protocol increases the test, maintenance, deployment and IT system overheads, so most DSOs are looking to consolidate around a master running a specific protocol for SCADA.

Virtual Access Mini RTU
Virtual Access substation hardened routers include a function called Mini RTU that provides protocol conversion allowing the DSO to consolidate on a single protocol. Even if it is not one of the protocols listed above, we are continually adding protocol support and can implement non-standard protocols.

Mini RTU includes the following functionality:

  • For connection from the master, it emulates an RTU that is the server, controlled station function.
  • For connection to an RTU, it emulates a master that is the client, controlling station function.

A data point mapper maps between the master and RTU protocols providing completely generic mapping between outstation and master, meaning that it can work with any outstation or master device.

The protocol table below shows the protocols currently available on our range of substation gateways.

ProtocolServer  (Controlled Station)Client (Controlling Station)
IEC 60870-5-104 (TCP)YesYes
IEC 60870-5-101 (Serial)YesYes
DNP3 SerialNoYes
Modbus TCPYesYes
Modbus SerialYesYes
IEC 61850YesYes


A key difference in our solution is the carrier-grade Activator provisioning and monitoring system designed to scale to tens of thousands of devices. This means that devices do not need to be pre-configured and can be installed without staff skilled in networking. The solution allows the DSO to maximise the level of process and field deployment automation by integrating with northbound IT systems and enables devices behind the VA router in the substation’s cabinets to be configured identically, while still being individually addressable from the central SCADA systems.

Protocol Gateway Summary

  • IEC 62351, DNP3, IEC 62443, Modbus
  • RS232, RS485
  • Digital I/O
  • Conversion at remote site
  • Central site application available
  • Deploy to same device everywhere to simplify maintenance
  • Substation-hardened device
  • Two seconds last GASP power


Key Benefits

  • Supports existing protocols
  • Supports IEC 62351 for future proofing
  • Single device provides multiple functions
  • WAN interfaces include 4G, fibre, DSL, dual radio, Ethernet
  • IP-rated, rugged device
  • Last GASP message for power failure
  • Rugged: high isolation options on the PSU and interfaces
  • Vibration and mechanical to EN standards
  • Roadmap includes analogue I/O and sensor inputs
Download as pdf