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Reason Switches - Digital substation Ethernet switches


The Reason Switches are fully flexible Ethernet switches for digital substations.  They provide highly-accurate time synchronization using IEEE1588 PTP and Gigabit Ethernet. 

The S20 & T1000 switches provide all the elements needed for the IEC 61850 digital substation network. It provides connections between IEDs that are flexible, reliable and robust, including those that are Precision Time Protocol (PTP) aware according to the IEEE 1588 v2 standard. 

A flexible, modular design allows these switches to support a wide range of different network architectures. It also allows speeds of up to 1 Gbps, as required in high-end process bus applications. The S20 is a fully Gigabit Ethernet switch. It supports up to 24 ports in 6 interface modules with 4 ports each. This model supports PTP (Precision Time Protocol) IEEE1588v2. The T1000 switch model supports up to 12 field replaceable ports with PTP (Precision Time Protocol). It also supports Rack, panel and DIN mounting.

IEDs can be time synchronised over the Ethernet network to an accuracy of less than 1us using PTP protocol. The switches can be set to operate as either a Transparent Clock or Boundary Clock. Also the internal NTP server provides a time reference to non-PTP aware relays.
Packet switching is implemented completely in hardware to ensure reliability and accuracy. This applies even when using a mixture of different copper and fibre interfaces. 

The S20 & T1000 switches can be configured and managed cyber-securely using an SSH command line interface or an HTTPS graphical interface. Both switches support RADIUS and TACACS+ remote authentication technology. Statistical management information can be accessed using SNMP v2/v3.

  • Fully flexible Ethernet switch for digital substations
  • Interfaces can be hot-swapped without reconfiguration
  • Uses include GOOSE, MMS, process bus, PMU, WAMS
  • Fully flexible, hot-swap interface modules
  • Hardened for substation applications
  • Cyber-secure configuration and management
  • Up to 20 Fast Ethernet (100Mbps) ports or Up to 4 Gigabit + 16 Fast Ethernet ports (S2020)
  • Up to 24 Gigabit Ethernet ports (S2024G)
  • Support for IPv4 and IPv6 protocols (Multicast, Unicast and Broadcast operation)
  • RSTP (IEEE 802.1D) and MSTP (IEEE 802.1Q)
  • Internal clock synchronization using NTP protocol
  • IEEE 1588v2 compliant (Precision Time Protocol – PTP) at all ports; (S2024G)

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