When Network Rail updated its legacy long line public address (LLPA) system at 39 stations operated by ScotRail it turned to ASL Safety & Security. ASL’s VoIP-based iPAM long line PA solution is operating from intelligent amplifier mainframes installed at individual stations.
ASL Safety & Security are working with Babcock Rail in Glasgow to deliver the replacement system that will serve the city centre and surrounding urban areas as part of an infrastructure upgrade.
ASL’s VoIP-based iPAM long line PA solution is operating from intelligent amplifier mainframes installed at individual stations encompassing an area as far as Newton, Barrhead and Neilston. Amplification is provided by modular amplifiers using proprietary Adaptive Class-D technology.
The IPAMs combine routing, Ethernet connectivity and loudspeaker line monitoring in a compact 2U fanless frame, which is tested for rail and other transport infrastructure applications. The Glasgow project uses iPAM400 amplifier units running the VIPA operating system. VIPA is ASL’s scalable Voice over Internet Protocol (VoIP) public address software, a library of IP-enabled solutions such as text to speech, message fragment storage and multicast functionality for Windows and Linux platforms.
ScotRail’s operational hub for the area is at Paisley. Here, the operator oversees the system’s front end using ASL’s mini-iVENCS PA/VA control and monitoring platform which offers real-time display of announcement zone status and translucent overlay of customisable PA/VA zones. iVENCS uses distributed architecture with a messaging backbone based on the Open Source XMPP messaging and presence protocol.
Ian Findlay, senior project engineer at Network Rail, said: “The adoption of this innovative technology in our stations will deliver a reliable and high-quality service to the travelling public and make journeys a more enjoyable experience by providing clear, up-to-date train information.”
Peter Andrews is ASL’s Head of Projects. He said: “Babcock Rail, in co-operation with Network Rail, has put together a well-engineered solution and a delivery team who are committed to working with ASL and Cisco as suppliers to provide an equipment replacement strategy that guarantees high-quality message delivery while working reliably on legacy copper. Another notable success was Network Rail’s unusual decision to record announcements using a member of staff. This has introduced a bright, fresh and friendly accent to Strathclyde’s commuters.”
He continued: “In contrast with the previous generation of public address systems, VIPA allows assembly of message fragments at the station level. Operators are merely triggering data that is stored locally. Telecoms engineers will immediately recognise the bandwidth efficiency and built-in redundancy of this approach.”