Medium Voltage OWF Array Cable Repair Joints (to 36kV)
For the offshore repair of medium voltage OWF array cables (to 36kV) damaged during installation or operation Power CSL offers its robust and reliable repair joint product.
The joint which has been designed for rapid offshore installation utilises cold-shrink insulation reinstatement technology and has been subject to rigorous testing to IEC specifications and CIGRE 490 and TB623 recommendations (mechanical / electrical / hyperbaric RWP).
The design is modular in nature allowing jointing of different cable designs and sizes. A single design of joint can be supplied with conversion kits allowing one joint to be used on all sizes of array cable within a wind farm. For example if an OWF utilises 240mm2, 500mm2 and 800mm2 array cables, one design of joint kit can be provided which covers repair of all cable sizes across the project. In some cases this offers the additional benefit that the OWF developer /operator can hold one size of repair cable (the largest), (ie) possible repair connections would be 240-240, 240-500, 240-800, 500-500, 500-800, 800-800.
From an Operations & Maintenance perspective one range taking repair joint can be configured to connect all cables across an operator’s entire fleet of OWFs, thereby allowing a centralised pool of repair joints. PCSL has supplied such range taking joints to operators of the majority of OWFs in UK / European waters.
The PCSL MV array cable repair joint has been successfully installed on a number of large OWF array cable remedial campaigns in recent years both in the UK and more recently in the US.
PCSL offer product familiarisation courses for its MV array cable repair joint to suitably experienced technicians. This approach facilitates a wider pool of available offshore technicians.
The joint utilises high tensile strength compression conductor connections. The insulation system is comprised of a one piece cold-shrink moulding with integrated stress control elements, developed by 3M, and selected and refined by PCSL for subsea applications following close technical collaboration.All joint bodies are electrically tested (HV & PD) as a standard routine QC measure. The combination of 100% electrical test, single piece construction, and cold-shrink application technique removes the potential for installer error that may arise from multi-component tube or tape based insulation reinstatement systems. Metallic core screen connections across the phase joints are configurable to accommodate all common cable designs.
The joint includes a stainless steel optical fibre splice enclosure(s) which incorporates highly adaptable bonding/earthing connection arrangements in order to accommodate different OF cable designs such as copper tube, stainless steel tube, Al armoured etc.
All internal components are housed within a marine grade resin filled, corrosion resistant, overall steel casing fitted with anodes. The product utilises high tensile strength armour terminations.
The repair joint can be supplied with bend stiffeners or bend restrictors to suit installation requirements.
Key features of the Power CSL medium voltage OWF array cable repair joint design :
Type tested to relevant IEC standards and CIGRE recommendations
95mm2 to 800mm2 conductor size range in copper or aluminium
Range taking 95mm2 to 300mm2 & 240mm2 to 800mm2
Accommodates XLPE or EPR based cable insulation systems
Accommodates all metallic screen options (eg) copper wire screen & copper tape screen with or without aluminium laminate layer, welded aluminium tube, extruded lead screen.
Suitable for wet, semi-dry or dry cable designs.
Accommodates all optical fibre cable design types including appropriate electrical bonding / earthing connections
Highly effective seals and resin protect against radial or longitudinal ingress of water into the repair joint (200 metre water depth)
Joint casing coated to Norsok standard and incorporates cathodic protection elements