PCP Splitter

For many Network Operators, the primary motivations for placing POTS splitters within the PCP copper cross-connection cabinet rather than the DSLAM cabinet is to reduce labour and material costs and increase capacity.

See the diagram below comparing splitter placement within the DSLAM (Figure 1.1) to splitter placement within the PCP copper cross-connection cabinet (Figure 1.2). This can conclude that fewer tie cables are required in Figure 1.2; therefore, POTS splitters give carriers greater flexibility and reduce materials/installation / civil costs.

Further details of cost savings/efficiency gains include:

• Reduce component costs: tie cables; racks; MDF Blocks.
• Reduce civil costs: fewer tie cables required between DSLAM and PCP.
• Reduce installation costs: carriers have greater flexibility by using few components within the DSLAM.
• Simplify installation: engineers have less volume of work to do when installing, and the task is also simplified.
• Maximise equipment density: higher density can be achieved in the DSLAM, enabling carriers to service more customers from a smaller footprint and optimising return on investment.

These are key enablers for carriers to more cost-effectively roll out Next Generation Networks such as VDSL and g.fast and optimise return on investment.

While the above advantages represent significant cost-savings, key problems associated with placing POTS splitter within PCP Copper Cross Connection Cabinet include:  

Environmental challenges: While these cabinets are sealed chambers, they do not have any heat or humidity control, and they are subjected to a constant condensation cycle and temperature cycling, which over time can result in a breakdown of the installed components. Ultimately, this results in faults, which require intervention by engineers in the network, making the total cost of ownership very expensive. 

High fault volumes: result in costly truck rolls for network maintenance and poor quality of service for the Subscriber. 

Tools: Many standard PCP splitters require the use of proprietary insertion tools, which, if used incorrectly or not used, will result in damage of the connector blocks and ultimately a breakdown in circuits

Electrical Performance: This is seriously negatively impacted due to a breakdown in Environmental Performance, as short-circuiting / arcing of the electrical circuits is a prevalent failure mode for the Printed Circuit Board on the splitter due to moisture exposure.

Therefore, it is essential, before selecting POTS splitters, that carriers work with material vendors in specifying the most ruggedised solution to ensure the Subscriber receives the highest possible quality of service. This will involve the operator selecting environmentally resistant materials to condensation/moisture, fully tool-less (to reduce installation complexity) and have excellent electrical characteristics (to future proof the network). 

To make matters more complicated, all these characteristics must be delivered in a compact footprint, given that the free space available is in the PCP cabinet is very limited. Key examples of this limitation are that the internal width available in the PCP cabinet is narrow, which can be challenging as the PCBs in xDSL POTS splitters require width to guarantee isolation in the electrical circuit. This is necessary to operate at the high frequencies needed by g.fast – 106/212MHz and mitigate against the chance of short-circuiting of the PCB).

It can be challenging to deliver all these characteristics into a compact footprint; therefore, fit-for-purpose items must be specified to develop a future proof solution that will minimise the total cost of ownership.

1. Environmental

DexGreen has designed a wide range of environmentally rugged xDSL POTS splitters (single pair / combined blocks), which are proven to address all problems faced by Operators in placing xDSL POTS splitters in the PCP

In order to achieve this, we place a high emphasis on design (from each individual component up to the complete solution) and it is essential that these designs are put through a rigorous ongoing test cycle at our test facilities, where they are subjected to continuous environmental cycling of damp heat, humidity, extreme temperatures. The purpose of this is to simulate the adverse conditions the PCP is subjected to within the PCP as a result of constant condensation cycling, which is very common in the PCP cabinet.

To pass these tests, we specify simple yet effective coatings which have been proven to maximise the durability of the electrical circuits / PCBs on the splitter modules and also gel-filling the connector blocks, which is a well-proven technology 

Key steps taken to maximise the Environmental Durability include: 

• Metal and component selection – optimised to ensure durability in the field
• Contact isolation – minimise the chance of high voltage breakdown and prevent electrical contact
• Conformal coating – beading of water to prevent component corrosion
• PCB design – optimised for isolation
• Approval testing – at a minimum, we test all POTS splitters according to the Environmental Engineering standard (ETSI EN 300 019-2-4), which simulates the harsh environment within a PCP copper cross connection cabinet.
• Expertise - Dexgreen has an expert team of electrical engineers who can optimise splitters to operate in any electrical network (VDSL / g.fast). We have many years expertise in supplying splitters to many operators. Therefore we can draw upon extensive experience. 

2. Electrical

DexGreen has developed a complete portfolio of ruggedised POTS splitters. This goal is to enable carriers to flexibly roll out Next Generation Network services (such as VDSL and g.fast) over the last mile of their legacy copper networks. 

Dexgreen works directly with carriers globally to sweat their copper networks, and POTS splitter technology is a natural complement to this offering.

We can add additional value by making the configuration of the components bespoke to the Operators application, which will ultimately result in a reduced total cost of ownership. Refer to Figure 2 below for key characteristics of our PCP splitter.

Figure 2

3. Qualification & Testing

Dexgreen qualifies its splitter technology according to globally recognised standards, which typically include:

• Electrical specifications: ETSI TS 101 952-1 (Access network xDSL splitters for European de- ployment; Part 1: Generic specification of xDSL over POTS splitters)
• Environmental specifications: ETSI EN 300 019-2-4 (Environmental Engineering (EE) Environmental conditions and environmental tests for telecommunications equipment. Part 2-4: Specification of environmental tests; Stationary use at non-weather protected locations). Typically environment-class 2.4H within this standard most accurately simulates a sealed PCP copper cross connection cabinet.

PCP Splitter technology enables carriers to quickly and cost-effectively roll out Next Generation Networks to their customers with minimal additional investment. Our experience is that if Operators specify materials that are not environmentally ruggedised, then regular network interventions will be required, resulting in frequent disruptions to the Subscribers service and total cost of ownership will be very high. DexGreen performs the full range of design, development, testing, validation, and training to ensure the carrier selects the optimum solution for its network, therefore minimising the total cost of ownership.

Key features of the PCP splitter include:

• Gel Encapsulation: The Splitter and the Tool Less Connector are gel encapsulated. It uses the same gel that has been thoroughly tested to meet the stringent requirements of the LN specification LN 753 issue 2. As proven in the LSA TL range, this environmental protection is essential in the PCP to guarantee reliability and performance. Well-proven technology with over 5 million connectors installed in the Access Network.
• Fully tool-less: The connector is Tool less fully compliant to the Openreach SOR. No Insertion tool is required.
• Test facility: The connector uses a standard approved two-pole test lead.
• User friendly: supported by comprehensive training and documentation. Essential design features are incorporated to facilitate ease of use for the Engineers.
• Jumper Management: within the PCP controlled and managed. This is a significant value given that the compact footprint within the PCP can get congested with jumper wires very quickly, therefore increasing the chance of faults.
• Tailored to Openreach requirements: Bespoke created kits for use within the PCP, Top hat and now Standoffs.