Cable Safety & Support
Main UK Stockists & Distributors of Cable Safety Products
Thorne & Derrick stock and supply a range of fixed, permanent and temporary support, protection and restraints increasing electrical circuit safety in the workplace. Cable management, support and protection is needed to combat external influences including short circuit, mechanical damage, temperature variations, water and other environmental and installation factors.
More Workplace Electrical Safety info ➡ | Arc Flash & Electrical Safety | Cable & Installation Tooling
Products including Cable Hooks for Safe LV MV HV Cable Installations & Temporary Support
From Substation to Socket | Safe LV HV Cables & Electrical Power Systems Up to 400kV
We provide Tooling & Electrical Equipment to Improve Workplace Safety.
Contact us with your Enquiry.
We protect substation engineers, asset managers, SAPS, cable jointers, overhead linesmen and utility workers with PPE and safety equipment: this includes insulating gloves, voltage detectors, insulating matting and portable earthing to ensure worker safety when carrying out repair and maintenance on LV-HV switchgear, transformers, substations and turbines.
All our Cable Connection & Energisation Accessories including Medium & High Voltage joints, terminations, connectors and cleats are tested to the latest international standards and supporting ranges of professional installation tools are stocked to reduce incident, accident and downtime to plant and people.
Tooling
Main UK Stockists & Distributors of Cable & Installation Tooling
Thorne & Derrick offer from stock a complete range of Cable & Installation Tooling for stripping, preparing, cutting, crimping and spiking low, medium and high voltage power cables including 11kV, 33kV, 66kV and 132kV-400kV polymeric cables.
Thorne & Derrick stock and supply jointing tools to enable the preparation of LV MV HV power cables prior to the installation of Joints, Terminations or Connectors – this includes precision engineered tools manufactured by Alroc to remove outer sheath/jacket, semicon screen (bonded or peelable) and insulation. The use of the correct jointing tools extend the service life of power cable systems and underground distribution networks.
Professional cable preparation carried out by trained Competent Cable Jointers is critical to prevent MV/HV cable termination and joint failures.
Our ranges of Cable & Installation Tooling also combine cutting-edge technology with innovation to provide Cut & Crimp solutions for all types of electrical cables and overhead lines – there is a selection of videos below and UK product demonstrations are available from Klauke and Cembre.
These Video Blogs show how cable preparation is vital for the performance reliability of stability of MV-HV cable joints and terminations – if cables are under prepared using sub-standard tools or basic hand tools then the risk incidence of future cable failure is increased.
More Workplace Electrical Safety info ➡ | Cable Safety | Arc Flash & Electrical Safety
From Substation to Socket | Safe LV HV Cables & Electrical Power Systems Up to 400kV
We provide Tooling & Electrical Equipment to Improve Workplace Safety.
Contact us with your Enquiry.
We protect substation engineers, asset managers, SAPS, cable jointers, overhead linesmen and utility workers with PPE and safety equipment: this includes insulating gloves, voltage detectors, insulating matting and portable earthing to ensure worker safety when carrying out repair and maintenance on LV-HV switchgear, transformers, substations and turbines.
All our Cable Connection & Energisation Accessories including Medium & High Voltage joints, terminations, connectors and cleats are tested to the latest international standards and supporting ranges of professional installation tools are stocked to reduce incident, accident and downtime to plant and people.
Klauke Orange Tools
Cable Cutting & Crimping Insulated Tools
Launched at ENERGYx2020 the KLAUKE Orange range of fully insulated tools manufactured by Klauke has set the standard within the global utility industry. Offering increased safety this range is the world’s first battery operated cable cutting and crimping tools with Tri-Insulation Barrier technology.
The orange housing of the battery powered cable crimping tool makes it easily differentiated from standard crimping tools and the built-in display allows user to view all tool data instantly.
Health & Safety is a main pillar of Energy Network Events and the KLAUKE Orange range is a huge leap forward in the development of battery-powered cabling tools for the cutting and crimping of overhead lines and underground cables.
You can find out more about ENERGYx2022 here: ➡ ENERGYx2022
You can view the complete range of KLAUKE Orange tools here ➡ insulated cable crimping and cutting tools.
The world‘s first battery hydraulic crimping and
cutting tools with Tri-Insulation Barrier technology that provides users with 1.000V protection against
electrical shocks.
There have been several recent advances in cable cutting and crimping tool technology including data recording, bluetooth remote controls and pressure sensors.
All tools have become more compact making them more efficient for jointing and terminating cables in confined spaces as well as enhancing safety features.
Training, supervision, testing and PPE are all standards but what the KLAUKE Orange implements is another layer of electrical safety into the process.
➡ Download Brochure Klauke Cutting & Crimping Tools
The Klauke Orange battery hydraulic Cutting- and Crimp Tools are VDE Approved in accordance to IEC 60900 and fully VDE Certified to IEC 62841-1. See the full Klauke Orange range in the video below.
Tri Insulated Barriers on Klauke Tools
During the interview below, Paul stresses the importance of safe working practices including the physical aspect of the tool e.g. the body insulation of the cable crimping or cutting tool. The new Orange Line Tool uses a 3 level or tri-insulation system – the 3 level includes creepage distance, insulation material and oil within the system.
Paul Morrow describes how Klauke was started in 1879 by two brothers in Germany originally making high quality pliers for the watch-making industry employing only 5 people. In 1960 when electrification become more popular Klauke shifted to developing cable lugs.
In 2018 they were acquired by Emerson and along with Greenlee and Rigid, Klauke can now service all the mechanical, electrical and plumbing requirements in the market.
For even more safety, Klauke has now developed the world‘s first battery hydraulic crimping and cutting tools with Tri-Insulation Barrier.
Before exhibiting at ENERGYx2020 Paul Morrow, UK & Ireland Manager from Klauke, part of the Emerson Group took part in an informative interview with Paul from Energy Network Events discussing electrical safety and the recent launch of the KLAUKE Orange range of fully insulated tools that have set the standard within the global utility industry.
“Since 1985, Thorne & Derrick have gained a solid reputation for contributing to improvements in Workplace Electrical Safety throughout the industry – this includes assisting the
launch of product innovations into the market, such as the Greenlee LS50 & Klauke VDE Orange and being a “go-to” supplier of electrical safety equipment to power industry contractors working with underground cables or overhead lines.
Increasing sales of our Strut Channel Cutter are an excellent example of a success story – the RIDGID STRUTSLAYR is recognised as the strongest and safest strut channel cutter on the market and is available from Thorne & Derrick stocks.
The sales and marketing staff at Thorne & Derrick worked hard and smart on introducing the STRUTSLAYR product to their clients and marketplace during COVID and are now seeing the impressive sales results.
Together during 2022 we welcome the opportunity to jointly promote more Workplace Electrical Safety improvements to be delivered through product innovations including the first remote-controlled cable cutters. For example, the Klauke ESG105RMCCFM and ESG65RMCCFM battery-powered, hydraulic cutting tools which will allow the user to maintain a safe distance whilst cutting cables,” comments Paul.
Energy Network Events exists to safely promote and further the interests of everyone working in and supplying the electricity industry. The management team have years of experience working in industry, organising and promoting events and use their experience and contacts to win the support of Legislators, Regulators, Senior Managers, World Class Suppliers and Inspirational Figures.
ENERGYx2022 Visitor Delegate FREE Tickets
ENERGYx2022 South Exhibitor Booking Form
ENERGYx2022 is the industry-leading Exhibition & Conference for anyone working within the Electricity Industry
LV, MV & HV Jointing, Earthing, Substation & Electrical Eqpt
Thorne & Derrick International are specialist distributors of LV, MV & HV Cable Installation, Jointing, Duct Sealing, Substation & Electrical Equipment – servicing UK and global businesses involved in cable installations, cable jointing, substation, overhead line and electrical construction at LV, 11kV, 33kV and EHV.
THORNE & DERRICK Product Categories: Duct Seals | Cable Cleats | Cable Glands | Electrical Safety | Arc Flash Protection | Cable Jointing Tools | Cable Pulling | Earthing | Feeder Pillars | Cable Joints LV | Joints & Terminations MV HV
Thorne & Derrick | Stockists & Suppliers | Joints Terminations Connectors up to 66kV
By Damon Mount | Head of Business Development at Megger
Cable Fault Location Equipment
An essential stage in the commissioning of any power cable is testing prior to energisation.
Properly performed, this test will provide the information needed to ensure that any problems that have occurred during the manufacture or installation can be corrected before they lead to costly and disruptive faults.
But what is the best way to approach post-installation cable testing?
Without any shadow of doubt, the first step is to get the cable preparation right and, if you are using a contractor to carry out the work, this means choosing one that can unequivocally demonstrate that they know what they are doing.
This may seem obvious but there are good reasons to be wary and, although this sounds paradoxical, one of the main underlying reasons is that modern cable test sets, such as those in the Megger range, are very easy to use.
This is undoubtedly a good thing overall, but a possibly unexpected side effect is that contractors with little or no cable test experience may believe that if they hire one of these test sets and quickly peruse the manual, they’re ready to offer cable testing services. They are not. There is much more to cable testing than simply knowing how to operate the test set, especially if the work is to be carried out safely and to deliver accurate results.
An experienced contractor will first formulate a safe method of work, and will manage the test area effectively and efficiently. It is important to keep anyone who is not involved with the testing away from the area, remembering particularly that there’s no visual difference between an energised cable and a de-energised cable.
This doesn’t just mean keeping members of the public away as colleagues acting as onlookers can be even more hazardous – they are the ones who are most likely to poke at the test set in an attempt to be helpful, and to offer distracting comments and suggestions.
The next step is to prepare the cable for test and, in particular, to prepare the cable ends so that, when carrying out a cable sheath test, there will be no flashover between the metallic sheath or screen and the semiconducting oversheath. Checking that the semiconducting material has been properly removed by carrying out a quick and simple test using an ordinary handheld insulation tester is always worthwhile.
TDR1000/3P Handheld TDR by Megger
It is now necessary to remove any cross-bonding links that are used in the cable system and it is essential to allow sufficient time for this. It is by no means unusual for a single link box to contain 30 or even 45 links. Removing these prior to testing and refitting them after testing will involve hours of work, something that those setting deadlines for testing often fail to realise.
With preparations complete, testing can commence, but there is another essential factor that needs to be considered – the right test equipment must be available on site.
This doesn’t just mean the test set that will be used for carrying out basic sheath testing, but also the additional equipment that will be needed to diagnose and locate the cable fault, if one should be found.
Few cable operators will be happy about the delays involved in returning to base to fetch more test equipment – it needs to be on site already, so that cable faults can be dealt with quickly and effectively.
This is another area where experienced cable testing contractors score. Since they carry out cable testing regularly, it is worth their while investing in a full range of test equipment and, just as important, in training their staff to use it safely and effectively. Companies that carry out cable testing relatively infrequently are unlikely to be able to match this level of investment and commitment.
The test voltage should, of course, be applied in line with the appropriate standards and specifications, and a good suggestion is that the test results should be written down on paper, even if they are stored in the instrument. The paper records may hardly ever be needed, but they are a simple and inexpensive precaution against stored results being accidentally erased or overwritten.
If all has gone well, it only remains to discharge the cable, issue the test certificate and, in the case of a contractor, send the client an invoice. Never rely on the test set alone, however, to discharge the cable! Even if the test set is indicating zero volts it takes only a few seconds to make sure the cable really is discharged by using a discharge stick. Failing to do so could, in the worst case, lead to a fatality.
What about those cases where a fault is found? The first thing to do is to STOP and assess the situation. Turn off the test equipment, discharge the cable and check that all connections at the local and distant ends of the cable have been made correctly. Re-test and, if the fault persists, decide on a testing strategy that will allow the fault to be diagnosed and located with the minimum risk of causing further damage to the cable.
This will typically involve the use of TDR to pre-locate the fault, and then a pin-pointer to find its exact location. Once again, it’s important to keep the crowds away, especially when using an acoustic pin-pointer, as footsteps in the vicinity can make it much more difficult to determine the precise fault location.
Pictured: Megger TDR1000/3P Cable Fault Location Equipment showing an LV underground mains cable fault. Fault location from substation at 104 metres. The images show an open circuit and then an issue 13 metres from point of electricity supply – this cable fault was caused by incorrect cable laying.
Accurate, dependable results are essential because, for the fault to be remedied, the cable will need to be excavated. This is a costly and time consuming task, so the risk of digging in the wrong place must be eliminated as far as possible.
It is always worth bearing in mind that post-installation sheath tests are relatively inexpensive to carry out and they are an excellent way of guarding against potentially costly future problems. A vital point, however, is to resist the temptation of opting for cheap solutions.
If you carry out the work yourself, make sure that you have the right equipment, that it’s calibrated and in full working order and that your staff are properly trained. Allow plenty of time for the work to be carried out – rushing work significantly increases the risk of making mistakes and, in cable testing mistakes can be fatal.
Megger TDR1000/3P Handheld TDR For Power Application
If you subcontract the work, choose your contractor with care – opting for the lowest price may well turn out to be false economy. Ensure that your chosen contractor has a proven track record in cable test and, bearing in mind the points discussed in this article, check that they will be able to cope efficiently and safely, even if the work turns out not to be straightforward.
Post-installation cable testing, properly carried out, is an excellent and very affordable form of insurance. But as with any other form of insurance it pays to check the details carefully and to avoid automatically opting for the cheapest option, unless you’re really sure that it meets your needs.
Electrical Test Equipment LV MV HV
Thorne & Derrick International are specialist distributors of LV, MV & HV Cable Installation, Jointing, Duct Sealing, Substation & Electrical Equipment – servicing UK and global businesses involved in cable installations, cable jointing, substation, overhead line and electrical construction at LV, 11kV, 33kV and EHV.
THORNE & DERRICK Product Categories: Duct Seals | Cable Cleats | Cable Glands | Electrical Safety | Arc Flash Protection | Cable Jointing Tools | Cable Pulling | Earthing | Feeder Pillars | Cable Joints LV | Joints & Terminations MV HV
Distributors for 3M Cold Shrink & Scotchcast | Nexans Euromold | Pfisterer Connex
Line Pulling Swivels By Slingco
Working Loads & Break Strength
Safety is critical when dealing with utility, construction or maintenance projects.
One of the main ways to ensure safety is by working within the load limits of crucial equipment. Slingco promote the safety critical role of cable support grips and the need for independent break load testing to safeguard project, people and reputations.
Swivels designed for use in stringing high tension wires for electrical transmission and distribution. Line Pulling Swivels are important in pulling when the lines develop torsion during the installation. This torsion must be released.
Use of a swivel will release torque and prevent it from reaching dangerous levels, which can cause damage to the cable or cable socks.
Slingco also offers a ‘bull nose’ style swivel designed for underground and overhead applications. All swivels are stringently quality tested and inspected to ensure optimum performance and reliability with working Loads from 10 to 134 kN.
This is the factor used to ensure sufficient break load to handle working load spikes. It is critically important that all devices and tools used for pulling conductor are rated for the working loads expected on each job.
Factor of Safety (FOS) is often notated as X to 1 or X:1. It is the ‘extra’ coverage of the breaking load over the working load expected. When pulling conductor or cable, many factors impact how much load your equipment must handle.
Sometimes the conductor can get hung up on something which will cause the load tension to spike. The factor of safety helps accommodate a normal spike without dropping wire or experiencing equipment failure.
Break Load must equal or exceed the Working Load x Factor Of Safety.
To help explain this, imagine the tension for a pull is calculated to be 1,800kg – this is Working Load of the pull. If the equipment used is only rated to a Break Load of 1,800kg, any variation in the load tension over the standard can cause failure. So, project designers assign a factor of safety (FOS).
This means that the Break Load of any tool used must be 3 times the expected load tension. In this example:
Working Load of 1,800kg x FOS of 3 = Break Load of 5,400kg.
Grips and swivels would need to be selected with a break load of 5,400kg or more.
When selecting equipment for a pull, be sure you know whether items are rated at BREAK LOAD or WORKING LOAD. If rated at working load, you must know the Factor of Safety this working load is based upon to ensure it matches your project’s working load. If rated at break load be sure it meets your project’s break load including the Factor of Safety.
Here are a few common rules of thumb for the Utility industry:
Pulling & Support Grips – usually rated at approximate BREAK load. This means a factor of safety for your project must be applied. To determine the working load, divide the break strength by your project’s Factor of Safety. For example, a grip with an approximate break load of 5,400kg to be used on a project with a FOS of 3:1 has a safe working load of 1,800kgs.
Swivels – This is where it gets tricky (or trickier). Most (but not all) manufacturers will label swivels at a 3:1 FOS working load. Slingco (along with two other prominent manufacturers of swivels) go ahead and CONVERT THE BREAK LOAD INTO THE WORKING LOAD. Our 2,240kg swivel is rated for a 6,720kg Break Load – we have already built in the Factor of Safety of 3:1.
Connectors – (90 degree, Rope to Rope, Rope to Swivel): Similar to swivels these are typically listed at their rated 3:1 WORKING LOAD. Connectors are used to connect grips when pulling though a tensioner or around an angle greater than 50 degrees. Swivels should not be pulled around a tensioner. Swivels are not designed to handle the side loads experienced when going around a tensioner wheel. This can cause damage to the bearing structure within a swivel.
These are only a few of the tools used. Remember to make sure you understand how each tool is rated (Working Load at what FOS or Break Strength). The key to ensuring a safe project is making sure all tools meet or exceed your project’s Working Load.
➡ Contact Thorne & Derrick for technical support on your cable pulling, laying and installation projects.
Cable socks and support grips are available to enable the installation of 33kV 66kV array cables prior to MV HV Jointing & Terminating in windfarm towers, turbines and offshore substations.
Further Reading
Specialist Distributors to the UK and international Offshore Wind & Renewable industry to provide safe and reliable LV HV Electrical Cable & Power Distribution Systems up to 66kV – we are highly customer responsive and absolutely committed to providing a world-class service. Contact our UK Power Team for competitive quotations, fast delivery from stock and technical support or training on all LV-HV products.
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