CatchBlock
CatchBlock OHL Catenary Roller From Slingco
Slingco has developed a range of products to vastly improve conductor replacement. The Catchblock, the Conductor Replacement Roller (CRR) and our range of specialist cable socks and grips.
The challenges faced by the OHL (Overhead Line) industry due to the growing number of electrical infrastructure projects built beneath existing transmission and distribution networks – alongside increasingly stringent OHL regulations – can make maintenance costly, time-consuming and challenging.
Replace OHL conductor in half the time with no need for possession orders
Lightweight, robust and easy to deploy, CatchBlock helps to increase efficiency and reduce costs.
CatchBlock is an innovative overhead line (OHL) catenary roller system.
A two-rope system, allowing the replacement of old-for-new conductors. In the event of conductor failure during this process, Catchblock enables the recovery of both ends without having to lower the system.
Removes the need to erect and dismantle scaffolding, significantly reduces the risk of accidents and harm to site workers and reduces cost and project timeframe.
Designed to deploy a twin-rope system, it allows the recovery and redeployment of broken conductors without the need to take possession of road/rail or client/third party property or infrastructure.
Provides a simple, conductor-deployed protection system using a lightweight aramid rope.
The CRR unit enables the safe exchange of conductors in three easy steps:
The rollers have a spring loaded gripping feature to secure the rope laterally without impinging any rotational movement as the rollers rotate around the axis of the conductor.
Complete range of LV, MV and HV cable pulling products for installation and enabling cable jointing in trench or ducts including LV, 11kV/33kV medium voltage (MV), 66kV/132kV high voltage (HV) and EHV transmission and distribution cables up to 400kV.
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.
➡ See Also Further Reading
Earlier this year, Thorne & Derrick welcomed Phil Day from Slingco Limited, the world-leading manufacturer of cable pulling and support socks, swivels, cable protectors, wire rope assemblies and accessories. Phil provided an Offshore Wind focussed company presentation to our Sales Team (pictured left-to-right Sarah Henderson, Carl Cox, Jonathan Hewitt, Phil Day, Jeff Jhanke, Natalie Lundie and Chris Dodds.
Cable Rollers | Duct Rods | Cable Socks | Cable Lubricant | Duct Seals | Cable Duct
Deputy MD, Paul Hopton, outlines the additional considerations in a wind turbine environment and highlights the potential consequences of arc flash incidents.
There have been a number of arc flash incidents and accidents reported on wind turbines. The arc flash hazards are similar for wind turbines as for other types of electrical installation. There are however some other things to consider with a wind turbine application:
Wind turbine damaged by Arc Flash
Let’s look at some of the accidents and incidents that have been reported1:
Looking at the incidents and accidents above, arc flash hazard and fires due to electrical faults are happening on Wind Turbines.
Here at Electrical Safety UK, we have carried out Arc Flash studies on a number of Wind Farms.
Does a typical wind farm installation differ much from other industrial type installations?
In general, the high voltage (HV) network that the wind turbines are connected to have incident energy levels well above 8 cal/cm2. The main reason for this is that the power distribution network that wind farm is connected to, can supply a significant amount of arc fault current into an arc flash event on the HV network.
We find a similar effect with conventional power stations that tend to have elevated levels of incident energy due to the fault levels available from their grid connection as well as their generators.
Interestingly, the contribution to fault levels from the wind turbines themselves is limited, as there is a solid-state conversion between the generator and the rest of the network.
If you would like more information or help in carrying out an Arc Flash Study, why not get in touch with us, using the form below? There is no charge for our initial pre-assessment visit. We would be happy to come and see you to discuss your requirements and, if required, provide you with a fixed price proposal for an Arc Flash study.
(References: Caithness wind farm Forum, http://www.caithnesswindfarms.co.uk/)
Electrical Safety Management is our core business. We provide expert consultancy and advice services for blue chip organisations across Europe concerned with the safe management of risk associated with all electrical work activities.
Electrical Safety UK provide a multi-faceted holistic approach including a full electrical safety management programme, project management and policy documentation all bespoke to the client’s requirements including fully accredited and bespoke training courses and personnel assessment programmes.
2 Genesis Business Park
Sheffield Road
Rotherham
S60 1DX
Tel: 0800 652 1124
Tel: 01709 961 666
Email: [email protected]
To find out more information click here
We protect substation engineers, asset managers, SAPS, cable jointers, overhead linesmen and utility workers with PPE and safety equipment: this includes insulating gloves, arc flash clothing, 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 of 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.
Electrical Safety In The Workplace
Identify Electrical Safety Hazards
You cannot smell, hear, or see electricity, so making sure you have the right systems in place to manage this hazardous energy is critical to the wellbeing of your employees and your Company.
There are two major hazards of electricity:
Electrical safety is important because hazards such as arc flash and shock can result in death if you are exposed to them. Fortunately, the likelihood of this occurring is relatively low. However, the control measures that prevent these hazards require careful management, attention to detail and technical competence.
Injuries that can result from electric shock are as follows:
Injuries that can result from arc flash are as follows:
Not surprisingly there is legislation in place that aims to regulate these electrical hazards. The three main ones are:
More Electrical Safety Products for LV MV HV Cables, Conductors, Substations & Overhead Lines
We will now try to answer the question: What should you have in place to manage electrical risk?
In a nutshell, it is important have an Electrical Safety Management System in place. What does that consist of, you may ask? It depends upon the size of your organization, but let us assume you are a large company, you should have something like the following in place:
Take our free electrical safety self assessment for a formal report on your current situation.
Within each category there can also be different levels of authorisation dependent upon the competency required to undertake certain tasks.
1. Electrical Competency Management System:
This should describe how you manage electrical competence, from recruitment through to technical competence requirements for each electrical role within your organisation.
2. Organisational Arrangements:
This should describe who is responsible for electrical safety and how your organisation is set up to manage electrical safety, including individual roles and responsibilities.
Electrical Safety Management is our core business. We provide expert consultancy and advice services for blue chip organisations across Europe concerned with the safe management of risk associated with all electrical work activities.
Electrical Safety UK provide a multi-faceted holistic approach including a full electrical safety management programme, project management and policy documentation all bespoke to the client’s requirements including fully accredited and bespoke training courses and personnel assessment programmes.
2 Genesis Business Park
Sheffield Road
Rotherham
S60 1DX
Tel: 0800 652 1124
Tel: 01709 961 666
Email: [email protected]
To find out more information click here
We protect substation engineers, asset managers, SAPS, cable jointers, overhead linesmen and utility workers with PPE and safety equipment: this includes insulating gloves, arc flash clothing, 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 of 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.
Thorne & Derrick | Jointing, Termination & Pulling Equipment
Have You Inspected Your Cable Socks?
Inspecting cable socks (also known as a cable grip and cable stocking) is not an exact science, but is crucially important to ensure safe cable pulling operations, maximum grip strength and grip longevity. There are a number of variables that can weaken cable socks that are not immediately obvious on visual inspection. However, there are some important and simple checks that you can do routinely to mitigate product wear, deterioration and potential accidents from happening.
When inspecting a cable grip, it is critical to know the potential damage and trouble spots. Below highlights the type of damage you need to be aware of prior to beginning any pulling project with your cable socks.
Safety is Slingco & Thorne & Derrick’s primary concern.
The products manufactured by Slingco are safety critical and must be used by competent trained personnel – it is essential to choose the right cable grip for the job. Inspecting a cable grip is not an exact science. There are a number of variables that can weaken a cable grip that are not immediately obvious on visual inspection.
This is why we work to Factors of Safety.
It is important to know the difference between Working Load and Approximate Break Load, and how to use the Factor of Safety to calculate the Working Load Limit for the cable grip that will be utilized. To maximize grip performance, we highly recommend utilizing banding on the ends of cable grips, as shown in the figure below.
Cable Grip Factor of Safety (FoS) *
The Working Load Limit (WLL), sometimes also known as the safety working load, is the mass that the equipment being used can safely hold, pull, or lower without breaking. In short, it’s the maximum load that can be applied to the product safely when in general service.
The Approximate Break Load (ABL) is the load at which a new grip can be reasonably expected to break. This is measured on a straight line pull only, as side pulling, or angular loads, will produce different results.
The Working Load is calculated by dividing the Approximate Break Load (ABL) by the Factor of Safety (FoS). No component in the system should exceed the working load for the cable grip.
The Factor of Safety (FoS) is the “extra” coverage of the breaking load over the over the working load expected. Factor of Safety is often noted as “X to 1” or “X:1”. The Factor of Safety accommodates normal spikes in load tension that may occur when under load.
Note: Slingco recommends double banding the ends of cable socks.
When you are inspecting a cable sock, it is critical to be able to identify damage or potential trouble spots. The following are some of the types of damage you should be aware of prior to beginning a pulling project with your cable grips. If these are observed, replacement of grip should be considered.
Pulling & Supporting Power & Subsea Cables in the Wind Sector | These cable socks manufactured from offshore/marine grade type 316 Stainless Steel are suitable for use in the renewable energy sector in applications such as cable installation (onshore and offshore), cable support inside wind turbines and cable management – used to pull, protect and support wind turbine cables. Pictured: June 2020 : the first of two export cables, each 37 kilometres in length, has been installed at the nearshore of Thorntonloch Beach as part of construction of the Neart na Gaoithe (NnG) Offshore Wind Farm.
Complete range of LV, MV and HV cable pulling products for installation and enabling cable jointing in trench or ducts including LV, 11kV/33kV medium voltage (MV), 66kV/132kV high voltage (HV) and EHV transmission and distribution cables up to 400kV.
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.
➡ See Also Further Reading
Earlier this year, Thorne & Derrick welcomed Phil Day from Slingco Limited, the world-leading manufacturer of cable pulling and support socks, swivels, cable protectors, wire rope assemblies and accessories. Phil provided an Offshore Wind focussed company presentation to our Sales Team (pictured left-to-right Sarah Henderson, Carl Cox, Jonathan Hewitt, Phil Day, Jeff Jhanke, Natalie Lundie and Chris Dodds.
Cable Rollers | Duct Rods | Cable Socks | Cable Lubricant | Duct Seals | Cable Duct
Special thanks to Jordan Edmenson at HVPD for the kind permission to republish Link to the original article can be found here
Monitoring & Location on a 33kV Offshore Wind Farm Export Cable
An offshore wind farm operator in the UK requested On-Line Partial Discharge monitoring and cable fault location on two 33kV XLPE land sea export cables to an offshore wind farm. The 33kV circuit began from a grid-connected onshore substation feeding a 2 km long land subsea transition joint, which in turn fed a 12 km 3-core cable directly to the offshore wind farm.
Short-term continuous monitoring was conducted using an HVPD diagnostic device connected to High Frequency Current Transformer (HFCT) and a Transient Earth Voltage (TEV) sensor.
Conducting short-term continuous monitoring over a number of days enables intermittent PD activity to be captured and correlated with other parameters such as load, temperature and humidity.
HFCT and TEV Sensors
If significant levels of PD activity were detected, fault location could be carried out using the cable mapping function of the HVPD diagnostic device. Cable mapping is conducted by detecting the an original PD pulse from the fault location as well as a reflected PD pulse (caused when the original PD pulse reaches the far end of the cable). Using the time delta between these pulses, and the signal propagation speed (which is provided in the cable data sheet) the approximate location of the PD source can be identified.
During the short-term monitoring period, high levels of PD activity were detected with the HFCT on Phase L3 of Circuit 1. Cable mapping on this circuit was then carried out to confirm the location of the fault, with the results indicating that the source was located 800m from the onshore substation.
This result was then corroborated with the cable schedule which confirmed the presence of cable joint no.7 at this location. Based on these findings, it was recommended that the affected joint no.7 be replaced. Following this replacement a forensic analysis on the joints was conducted in which significant insulation damage and tracking within the inner insulation section was found.
Partial Discharge Map Showing PD Location
Forensic Examination of Cable Joint
PD Trend Line Before Replacement
PD Trend Line After Replacement
During the short-term monitoring period, high levels of PD activity were detected and cable mapping on this circuit then confirmed the location of the fault. The affected joint was able to be taken out of service and replaced during a scheduled outage, avoiding the risk of an in-service cable failure.
HVPD supplies a comprehensive range of equipment to detect and monitor On-line PD for the condition assessment of in-service power cables, switchgear, motors and generators, and transformers rated at 3.3kV and above. Our PD testing and monitoring technology provide you with an early warning of developing insulation faults, helping you to avoid costly failures and resulting unplanned network outages.
To find out how we can test and monitor your cable network for PD and locate any faults, terminations or joints, get in touch today at [email protected] or call us on 0161 877 6142.
Established since 1985, T&D International based in the UK distribute the most extensive range of LV, MV & HV Cable Jointing, Terminating, Pulling & Installation Equipment – contact us today for a competitive quotation.
Key Products : MV Joints & Terminations, Access Chambers, Cable Cleats, Duct Seals, Cable Transits, Jointing Tools, Feeder Pillars, Cable Duct, Earthing & Lightning Protection, Electrical Safety, Cable Glands, Arc Flash Clothing Protection & Fusegear.
Distributors for : 3M, Pfisterer CONNEX, Nexans Euromold, Elastimold, Catu, Roxtec, Emtelle, Centriforce, Lucy Zodion, Alroc, Cembre, Prysmian, Ellis Patents, ABB & Furse.
T&D Providers Of Jointer Training Courses By Pfisterer CONNEX & Nexans Euromold
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