Image Courtesy of: Emil Zlatev (Trainer & EHV Cable Jointer At Pfisterer)
Pictured: Pfisterer EST145 Dry Outdoor Substation Cable Terminations
The PFISTERER group has been dealing with the interfaces in the flow of electricity ever since it was founded in 1921.
As a specialist in energy transmission and distribution, PFISTERER offer a range of sophisticated, future-ready products. For all voltage ranges and wherever reliable, long-lasting systems are needed for powerful energy grids.
As well as the energy sector, PFISTERER are also active in transport technology and industrial solutions. They are well-established in all key global markets and continue to strengthen the brand on a worldwide scale.
The IXOSIL product range of cable terminations and joints for HV power cables includes slip-on joints for the entire spectrum of voltages from 72.5 kV to 550 kV – in each case with different shielding designs, with or without bonding or grounding cable.
The joints consist predominantly of pre-manufactured and routine tested silicone components, are water-resistant and optionally available with permanent metal, plastic or shrink-fit enclosures.
The well proven slip-on technology permits fast installation and the secure connection of cables with extruded insulation with copper or aluminium conductors. The electrical conductors are permanently connected using advanced SICON bolted connectors or conventional compression connector. Combinations of cables with different conductors and shielding systems are also possible.
IXOSIL Joints for Permanent Cable Connections
Thorne & Derrick are Main Distributors & Stockists for the PFISTERER range. Established since 1985, T&D distribute the most extensive range of LV, MV & HV Cable Jointing, Terminating, Pulling & Installation Equipment – contact us today for a competitive quotation.
Subscribe now to our POWER NEWSLETTER– a monthly email circulation packed with news, projects, videos, technical tips, training information, promotions, webinars, career opportunities and white papers.
Includes access to our popular JOINTERS BLOG with contributions from utility professionals, linesmen and cable jointers working on MV HV EHV cables and overhead lines typically at 11kV, 33kV, 66kV and up to 132kV.
15,000+ Subscribers. ➡ 
Thorne & Derrick | Elcon Megarad Distributed from Stock | Approved Supplier
UK & Export Sales
Thorne & Derrick can provide expert technical support, customer service and competitive prices with delivery from extensive stocks for the complete range of Elcon Megarad products.
Elcon Megarad is an Italian company which designs, manufactures, tests and markets cable accessories and components for medium/high voltage power grids around the world. Research and Development is constantly engaged in developing new materials and technologies, with particular attention to the different market demands.
Their chemical-physical characterisation laboratory and high voltage (HV) test room enable the design and development of a wide range of cable terminations and junctions for all types of cables on the market, according to CENELEC standards, to be performed with maximum reliability.
LV Heat Shrink Branch Cable Joints | Elcon Megarad
Elcon Megarad offer a wide range of high performance low voltage cable accessories, including resin cable joints, re-enterable straight/branch gel joints, heat shrink cable joints and heat shrink cable terminations. Each Elcon Megarad LV cable joint and cable termination includes a robust and easy to assemble components kit.
The complete range of LV cable joints and terminations are compliant with CENELEC HD 623 & CEI EN 50393 standards, which both require a low voltage cable power distribution of 0.6kV/1.0kV.
MV Heat Shrink Cable Terminations | Elcon Megarad
The extensive Elcon Megarad collection of high performance medium voltage cable accessories offer wide variation of products. Medium voltage cable terminations range from, both indoor and outdoor cold shrink/heat shrink cable terminations, heat shrink trifurcation kits, porcelain cable terminations and cable connectors. Elcon Megarad’s MV power cable joints include, cold shrink cable joints, heat shrink cable joints and resin cable joints.
Additionally, MV stock extras include medium voltage single core cable connections pre-assembled with cable terminations, as well as MV cable joints and cable terminations designed for renewable energy and wind farm applications, available in both heat shrink and cold shrink variants.
All MV cable accessory stocks are compliant with CENELEC HD 629.1 S2 & CEI 20-62/1 or CEI 20-62/2 standards, meeting the test requirements of rated voltage from 3.6kV/6kV up to 20.8kV/36kV.
HV Heat Shrink Cable Terminations | Elcon Megarad
Offering an uncommon stock of high performance HV heat shrink cable joints and cable terminations. Elcon Megarad’s High Voltage Heat Shrink Cable Termination 66kV/72.5kV & High Voltage Heat Shrink Cable Joint 66kV/72.5kV are available with an extensive heat shrink cable termination and cable joint selection guide, including details on product application and kit components.
The Elcon Megarad range of HV heat shrink cable joints and cable terminations are compliant with IEC 60840 & IEEE 404 standards, making them suitable for direct burial and underground cables located in cable trenches up to 72.5kV.
Subscribe now to our POWER NEWSLETTER– a monthly email circulation packed with news, projects, videos, technical tips, training information, promotions, webinars, career opportunities and white papers.
Includes access to our popular JOINTERS BLOG with contributions from utility professionals, linesmen and cable jointers working on MV HV EHV cables and overhead lines typically at 11kV, 33kV, 66kV and up to 132kV.
15,000+ Subscribers. ➡
Safely Sealing LV HV Cables & Electrical Equipment
Due to the ever-changing data centre environment Roxtec seals were installed on several centres built for a multi-national technology company throughout the USA.
With service continuity as a top priority, the company selected Roxtec system of cable transits as a cable sealing solution.
Roxtec seals would both protect their equipment and provide flexibility for continued growth. Site superintendents, project managers and installers of contractors Structure Tone, IES and Hunt Electric also consider Roxtec a best-fit solution for the industry. Jim Wagner, Senior Project Manager at Hunt Electric coments, “Roxtec is a great product, the best I have seen in the market based on flexibility.”
Project Description – Construction of data centre in multiple locations in the USA
Owner – Multinational technology company
Installations – Structure Tone, IES, and Hunt Electric
Applications – Walls, trenches and cable trays
Sealing Requirements – Fire-proof, watertight and air-tight
Future Capacity Included
The HVAC systems, power equipment and communications equipment must be updated continuously. Our openable and adaptable seals make it possible to leave room for future capacity. You can easily make changes and upgrades without cutting a new hole. This allows for a dustless re-entry into your contained sensitive environment. Roxtec offers a long-term partnership to protect your data centres and server halls against multiple risks such as fire, flooding and air leakage.
Unbeatable Sealing & Protection of Cables
Roxtec provided sealing solutions for both exterior and interior penetrations keeping water and fire from causing damage and downtime all while providing airtightness and increasing the efficiency of the data centre.
Contractor Approved
Roxtec seals are easy to install, adapt and reseal. Ross Catlett of IES states:
“It is significantly easier to install Roxtec than using solutions like foam and the bags that you have to pack and fill in.”
After participating in Roxtec’s training and becoming an approved installer he can now train new employees as they come onsite or continue on to future projects.
Roxtec cable seals are used in cable vaults, duct banks, electrical substations, trenches and M&E building services protecting low, medium and high voltage power systems against numerous external risk factors:
➡ Further Reading | Connecting High Voltages & Energising Data Centres
Thorne & Derrick distribute the most extensive range of Cable Installation & Electrical Distribution Equipment to the Power Transmission & Distribution industry in the onshore and offshore wind, solar, rail, oil/gas, data centre, battery storage and utility sectors.
We service UK and international clients working on underground cables, overhead lines, substations and electrical construction at 11kV and up to and EHV transmission and distribution voltages.
LV – Low Voltage Cable Joints, Glands, Cleats, Lugs & Accessories (1000 Volts)
MV HV – Medium & High Voltage Cable Joints, Terminations & Connectors (11kV 33kV EHV)
Conference Name: Subsea Power Transmission & Cabling 2021
Dates: 16-17 September 2021
Start: September 16, 2021 13:00
End: September 17, 2021 17:00
Location: Virtual Event – Find out more here
Email: [email protected] Prospero Events Group helps decision-makers in the European energy industry benchmark best practices by organizing peer-to-peer conferences.
➡ 50% discount if booked before 30th June 2021 – BOOK NOW!
With the growth of offshore power production and in order to meet net-zero, it is important to ensure high quality and reliable offshore grid infrastructure to integrate the growing offshore power production. Infrastructure development is also important to ensure the security of supply and to ensure cross-border energy trading. Talking about infrastructure development, new challenges in cable technology, design, installation and maintenance needs to be addressed as well.
Subsea Power Transmission & Cabling 2021 will bring together the most prominent European energy industry leaders in an exclusive closed-group and business-friendly environment for peer-to-peer networking to discuss challenges and opportunities of the strategic role of submarine power cable infrastructure, subsea power transmission and infrastructure development to support the expansion of offshore wind production and to secure the stability of power supply by sharing their business models and latest studies.
Bringing together decision-makers responsible for subsea power cables and offshore power transmission to discuss challenges and opportunities of the strategic role of submarine power cable infrastructure, subsea power transmission and infrastructure development.
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Bart Goethals CCO, Nemo Link, Belgium
Bart is in charge of the commercial aspects of the Nemo Link interconnector between Belgium and England which is the first ‘cap and floor’ interconnector.
Over the last ten year he has been working on multiple interconnector and offshore grid investment files.
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Dr. Lorenz Müller, Head of Regulatory Affairs, 50Hertz, Germany Lorenz Müller was born in 1972 in Dortmund, Germany. He studied electrical engineering and received a PhD at the Technical University of Dortmund, Germany. In his professional career, he has executed different management positions in the company, e.g. responsible for grid usage and connection contracts, energy market development and the whole energy business of the company. |
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Dennis Stufkens, Operations Directors, BritNed, The Netherlands
BritNed Development Limited is an international organisation with sites based in Great Britain and the Netherlands. They own and operate the electricity interconnector between Great Britain and the Netherlands and deliver world class asset reliability, vital to the energy needs of Great Britain and the Netherlands, and they do with it with a key focus on safety. |
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Margot Van Nuffel, Project Finance Manager, Otary, Belgium Since 2017 with Otary (Belgian knowledge centre for offshore wind energy that develops, finances, constructs and operates offshore wind parks) as the project finance manager. Leading the negotiations with Elia in 2019 on an asset sale to complement the Modular Offshore Grid, and assisting in the financing of SeaMade in 2018, the largest Belgian offshore windfarm. Responsible for the PPAs and the regulatory/market aspects of 800 MW of offshore wind assets. |
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Luke Wainwright, Offshore Coordination Manager, National Grid ESO, UK Luke Wainwright is an experienced leader in the Electricity System Operator for Great Britain, National Grid ESO. He has worked for National Grid for 20 years in a variety of Commercial, Project and Operational Leadership roles, including the leading the New Connections team for England and Wales and being Chief of Staff to the Director of Operations. At present he leads on Offshore Coordination, specifically the change programme to ensure the System Operator can achieve 40GW by 2030 whilst also balancing the needs and interests of coastal communities and consumers. |
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Aoife Wixted, Senior Lead Engineer, Eirgrid, Ireland
EirGrid develop and operate the national electricity grid, so that everyone has power when and where they need it. The grid takes electricity from where it is generated and delivers it to the distribution network, operated by ESB, which powers every home, business, school, hospital, factory and farm on the island. They also supply power directly to some of Ireland’s largest energy users. |
Prospero Events help decision-makers in the European energy industry benchmark best practices by organizing peer-to-peer conferences.
Their promise is to offer the longest average minutes (at least 4 minutes per participant within two days of a virtual event) of direct peer-to-peer networking with the most senior, relevant, committed, innovative, and open-minded European professionals about specific energy industry-related topics.
Thorne & Derrick distribute the most extensive range of Low & High Voltage Cable Installation & Electrical Distribution Equipment to the Power Transmission & Distribution industry in the onshore and offshore wind, solar, rail, oil/gas, data centre, battery storage and utility sectors.
We service UK and international clients working on underground and subsea cables, overhead lines, substations and electrical construction at LV, 11kV/33kV and up to and EHV transmission and distribution voltages.
Key Products: MV-HV Cable Joints & Terminations, Cable Cleats, Duct Seals, Cable Transits, Underground Cable Protection, Copper Earth Tapes, Cable Jointing Tools, Feeder Pillars, Cable Ducting, Earthing & Lightning Protection, Electrical Safety, Cable Glands, Arc Flash Clothing & Protection & Fusegear.
Distributors for: 3M Electrical, ABB, Alroc, Band-It, Cembre, Centriforce, CMP, Elastimold, Ellis Patents, Emtelle, Furse, Lucy Zodion, Nexans Euromold, Pfisterer, Polypipe, ProGARM, Prysmian, and Roxtec.
Cable basement KW Schattenhalb, Switzerland (c) 2014 Damian Aegerter
Special thanks to Damian Aegerter at Braavos GmbH / cableizer.com
for the kind permission to republish
In this 3rd article about cable pulling we discuss the usage of the weight correction and sidewall bearing pressure factors plus the conduit jamming ratio.
Transportation, handling, and installation of cables causes often more mechanical stress than what is actually experienced during operation. Therefore, it is important to carefully plan the cable installation, which can be done in Cableizers updated cable pulling module.
The conductors of the cable are generally the only members that can bear the pulling forces without damage. Do not use metallic shielding wires, tapes, braids or armor not designed for the purpose in pulling tension calculations.
Pulling different conductor sizes at the same time is not recommended if the conductor size or other cable characteristics are significantly different. If you must pull different size conductors, it must be done with care.
Pulling additional cables into an existing conduit system is generally not recommended. If this must be done, extreme caution must be taken. Of special concern is the cutting action of the tensioned pulling rope.
Usage of weight correction factor
When multiple cables are pulled together, their mechanical configuration in the conduit is changing along the route which exposes them to uneven forces, an imbalance that is causing additional frictional drag. The weight correction factor f_wc is taking this into account by increasing the weight of cable assemblies consisting of more than one single cable.
Formulas for weight correction factors are mostly limited for pulling of up to 3 cables. Some formulas exist for pulling cable assemblies of 4 cables, but they were not leading to consistent results. Cableizer has extended the formulas for cable assemblies of up to 6 cables.
The following examples are calculated with a cable with an outer diameter D_e of 37 mm and a conduit with an inner diameter D_id of 150 mm. In addition, all calculations are also done on the example of a very large conduit (Di_d = 10 m) for validation reasons.
In this case, the cables lie next to each other and do not rub against each other, and the weight correction factor should be negligible (i.e. equal to 1.0).
As can bee seen in the following table, this is the case except for 5/6 cables which have a constant weight correction factor independent of the cable and conduit dimensions. As a consequence, the pulling force calculation in Cableizer for large conduits is rather conservative (i.e. on the safe side).
The above figures show that the weight correction factor is as expected incrasing with an incrasing number of cables pulled together.
Cradled configurations do have higher weight correction factors than when the cables are more organized (3 cables triangular/triplex or 4 cables diamond/quadruplex). If you are close to or exceeding the pulling force limits, it can therefore be of interest to investigate if binding the cables together can be an option.
Generally, manufacturers do also consider the influence of the weight correction factor when calculating the sidewall bearing pressure.
In Cableizer, this is considered with the sidewall bearing pressure factor f_rad, which can be optionally selected. Its calculations is always dependent on the weight correction factor, but it can be applied to the calculations independently of the weight correction factor. A normal use case is to either apply both f_wc and f_rad or none of them.
The following examples are calculated with a cable with an outer diameter of 37 mm and a conduit with an inner diameter of 150 mm.
The sidewall bearing pressure F_rad is proportional to the sidewall bearing pressure factor and the pulling force. The pulling force F_pull itself is proportional to the weight correction factor and the gravitational force. The gravitational force F_g itself is proportional to the number of cables N_c being pulled together.
As a consequence, the factor f_rad⋅f_wc⋅N_c indicates to what extent the sidewall bearing pressure is increased as compared to the case where a single cable is being pulled.
The above figures show that the sidewall bearing pressure on the most exposed cable is increasing steadily with an increasing number of cables being pulled. As expected, cradled configurations do have lower sidewall bearing pressures than when the cables are more organized (3 cables triangular/triplex or 4 cables diamond/quadruplex).
Jamming is the wedging of three unbound cables when pulled into a conduit. This usually occurs because of crossovers when the cables twist or are pulled around bends. The conduit jamming ratio is the ratio of the conduit inner diameter Di_d and the cable outside diameter D_e. When calculating jamming probabilities, a 5% factor is used to account for the oval cross-section of conduit bends. The cable diameters should be measured, since actual diameters may vary from the published nominal values.
Cableizer indicates the risk for jamming according to the following table. As shown, different references use different ranges for quantifying the jamming risk. Cableizer does only indicate the jamming ratio for Three cables unbound because even while jamming can occur when pulling four or more cables into a conduit, the probability is very low.
Always follow the instructions from the cable manufacturer when preparing your cable pull. While some manufacturers disregard the use of the weight correction factor (example I from Brugg Cables), others include it in their calculations (example II from Southwire). In Cableizer, both options can conveniently be calculated.
Cableizer specifically disclaims any warranties, including, but not limited to, the implied warranties of merchantability, accuracy, or fitness for any particular purpose of its calculation results.
The original article can be found on LinkedIn here
Cableizer – The Online Cable Optimizer
Model power cables and calculate current rating, magnetic fields, electrical parameters, short-circuit currents, pulling forces… Experience the full potential of our browser-based simulation platform cableizer.com! Our 14-day free trial includes full access to all the simulation features of Cableizer.
View the other blogs in the Cable Pulling Blog Series below:
Thorne & Derrick distribute the most extensive range of Low & High Voltage Cable Installation & Electrical Distribution Equipment to the Power Transmission & Distribution industry in the onshore and offshore wind, solar, rail, oil/gas, data centre, battery storage and utility sectors – this includes the most extensive range of Cable Pulling & Cable Laying Equipment to enable the installation of low, medium and high voltage power cables into underground trench or duct.
We service UK and international clients working on underground cables, overhead lines, substations and electrical construction at LV, 11kV/33kV and up to EHV transmission and distribution voltages.
Key Products: MV-HV Cable Joints & Terminations, Cable Cleats, Duct Seals, Cable Transits, Underground Cable Protection, Copper Earth Tapes, Cable Jointing Tools, Feeder Pillars, Cable Ducting, Earthing & Lightning Protection, Electrical Safety, Cable Glands, Arc Flash Protection & Fusegear.
Distributors for: 3M Electrical, ABB, Alroc, Band-It, Cembre, Centriforce, CMP, Elastimold, Ellis Patents, Emtelle, Furse, Lucy Zodion, Nexans Euromold, Pfisterer, Polypipe, ProGARM, Prysmian, and Roxtec.
Thorne & Derrick International, based in the UK, are delighted to announce they have entered into an Approved Stockist Agreement with SEB International, the market-leading Cable Laying Equipment manufacturer.
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