Functional Supply Points | FSP01/02 FSP03 FSP04

FSP Switchgear FAQs

What’s the difference between FSP01, FSP02 and FSP03?

The term FSP can be a confusing one on the railway. It is used to describe both the switchgear product and the assembly housing which it is housed in. This is further confused by the fact that there are different types of FSP depending on the power distribution architecture.

• FSP Switchgear – this is the product that connects the signalling power distribution system to the functional circuits. It consists of terminals, isolation switches and protection devices. These products are manufactured to meet the specific needs of FSP01, FSP02, FSP03 and FSP04 architectures as detailed below.
• FSP Assembly – this is typically a standard half or full width location case with yellow banding. As well as the FSP Switchgear it will also contain additional equipment required which may include isolation transformers, insulation monitoring, auto-reconfiguration equipment, battery chargers, protection devices, Distribution Interface Transformer Assemblies (DITA).
• Class I Equipment – this relies on basic insulation and for all exposed-conductive-parts of an installation to be connected to a productive conductor (see BS EN 61140 and BS7671). This normally means that the switchgear product is made of steel but is grounded via a protective earth. Class I products are used for FSP01 and FSP02 systems only.
• Class II Equipment – this relies on both basic insulation and supplementary insulation to provide protection (see BS EN 61140 and BS7671). This normally means that the switchgear product is made of a non-conductive material (GRP, plastic) and features a Class II label on the front. Class II products are used for FSP01, FSP02, FSP03 and FSP04 systems.
• Class II Hybrid – this is where the installation on the primary side of a transformer meets the requirements for Class II and the installation on the secondary side of the transformer meets the requirements for Class I (see NR/L2/SIGELP/30007). This is typically found where upgrades are being carried out to an older system, and the upgrade parts need to meet higher standards. Class II Hybrid products are used for FSP01, FSP02 and FSP04 systems.

FSP01 – this is the simplest and therefore most cost-effective architecture. A single supply source at one end feeds power to the FSPs which are daisy chained together. This may also be used where a sub feed (spur) from a main distribution system is required.

FSP02 – this is a more complex architecture that has greater redundancy and resilience. The FSPs are still daisy chained together but now there is a supply source at each end. This means that in the event of a single failure the system can be manually re-configured to run off a single supply at either end of the system.

FSP03 – this is the most sophisticated solution. The arrangement is the same as for the FSP02 architecture but with the addition of the ability to have an Auto-Reconfiguration System (ARS). An ARS system can automatically detect a failure from one supply end and automatically reconfigure the system, to run using the other working supply end, thus ensuring complete reliability even in the event of a failure.

FSP04 – there are a lot of old legacy single end fed systems on Network Rail infrastructure. Where these are still being used the power distribution systems were never designed or built to comply with modern standards and are therefore potentially unsafe. FSP04 switchgear has been designed to allow a simple and cost-effective upgrade to these old legacy installations without the need for expensive wholesale upgrades of the entire architecture.

RSP Switchgear can be purchased as standalone products for fitment in existing installations or they can be purchased as part of an overall FSP Assembly.  RSP can configure, design, build, factory test and deliver to site a full range of FSP01, FSP02, FSP03 and FSP04 Assemblies to meet any specification.  We offer modular solutions as well as bespoke builds and we are proud to be the only company to offer a Network Rail approved Class 1 FSP Switchgear product.

What Are Functional Supply Point FSP?

Rail Functional Supply Points (FSP) are the equipment tasked with the electrical supply of signalling power distribution throughout the rail infrastructure. RSP’s range of rail power products cover all installation requirements – from a rail legacy changeover of a single piece of rail switchgear or FSP switchgear assembly to full FSP equipment housing, offering multiple power supplies and auto reconfiguration facility.

Do your FSPs comply with Network Rail standard (NR/L2/SIGELP/27409 Issue 2)?

RSP’s full range of FSP switchgear assemblies are all in accordance with Network Rail standards NR/L2/SIGELP/27409 Issue 2.  See Functional Supply Points FSP01/02 Technical 

Do your FSPs work with Auto-reconfigurable systems (ARS)?

Yes, our FSPs work with Auto-reconfigurable systems (ARS). RSP’s range of rail power products cover all installation requirements, offering multiple power supplies and auto reconfiguration facility.