The Tyne and Wear Metro system, connecting Newcastle, Sunderland and surrounding communities in north-east England, was Britain’s first modern urban mass transit system.

An important part of the £350m Metro: All Change modernisation programme, which is now underway, was the selection and installation of a customer information system in the 90-strong metrocar train fleet. This was to provide more clearly audible pre-recorded announcements and the same message will be displayed in carriages to aid hearing impaired passengers.

The selection of the CIS was based on criteria gained from discussions with interested parties from all selections of society, particularly people who would benefit from an improved and much enhanced travelling experience, including those who are blind, partially sighted and deaf or hard of hearing.

For the on-board communications elements of the system, Nexus, the public body which owns and manages Metro, together with Interalia chose the SDW-550, a five-port unmanaged Ethernet switch from industrial data communications specialist Westermo. This is a vital component in the on-board communications network, providing a pathway between the CIS and the CCTV systems to facilitate the sharing of data.

The reason for choosing the SDW-550 was because of its high industrial specification and the fact that it worked perfectly even when connected into CAT3 cable.

The SDW-550 is a ‘plug & play’ DIN rail-mounted, five-port unmanaged industrial Ethernet switch with five 10/100Mbit TX (copper) ports.

The switch is tri-galvanically isolated with up to 2.8KV isolation between interfaces and the power side, and a 1.5KV between interfaces with a wide 9.6V to 57.6V DC input power range with polarity protection, as well as being able to accept power from two sources.

With extended temperature range supported as standard, the SDW-550 is a basic switch designed to be used in the harshest of environments.