Image Credit: Eclipse Power Networks
uploaded by Chris Dodds - Thorne & Derrick Sales & Marketing Manager
Thorne & Derrick, Specialist UK Distributors of LV HV Jointing, Earthing, Substation & Electrical Eqpt up to 66kV, provide expert technical specification, customer support and product supply from stock of an extensive range of Hazardous Area Electrical Equipment – this includes Power, Heating & Lighting products with ATEX Certification for installation in Substation Battery Rooms.
Explosive Flammable Gases/Vapours
UK DNO’s detail safe working procedures and rules in their Document Manuals to be followed when working on alkaline or acid substation batteries and storage rooms located within primary network medium/high voltage substations (MV HV).
Lead-acid type batteries release potentially explosive hydrogen gas when charging – this is the primary explosive risk associated with medium/high voltage substations.
Consequently, these worksite locations are classified as hazardous area Zones according to the ATEX Directive – a “hazardous area” is defined as an area in which the atmosphere contains, or may contain in sufficient quantities, flammable or explosive gases, dusts or vapours. The Zone designation depends on the level of risk and likelihood of flammable gas, vapour or mist forming during normal operation.
ATEX is an abbreviation of “Atmospheres Explosibles” and is a set of European Union regulations that are designed to ensure the safety of electrical products being used in potentially explosive atmospheres.
Thorne & Derrick, Experts in Equipment for Explosive Atmospheres, provide Zone 1/Zone 2 (Flammable Gas) ATEX Compliant electrical equipment for installation in substations and battery rooms to provide heating, lighting and power distribution.
The main Dangers to Persons carrying out work or testing on batteries and chargers are electric shock, explosion or burns arising from the ignition of flammable gas which is emitted by cells during the charging process.
Flammable gas can be ignited by naked flames (eg “hot-working” by cable jointers), cigarettes or by sparks if cell terminals are accidentally earthed or shorted together.
This short-circuiting releases dangerous levels of heat, light and arc energy.
Consequently, electrical equipment installed in MV HV substation battery rooms should be Zone 1 or Zone 2 certified according to ATEX Directive for safe installation in such potentially explosive atmospheres.
♦ Primary Network Substation: a 132kV, 66kV, 33kV or 25kV substation including directly associated 66kV, 33kV, 25kV, 11kV and 6.6kV switchboards at transformer stations (Definition: WPD Engineering Specification EE Spec 25/5).
How We Can Help?
♦ Lighting – T&D can provide lighting designs to ensure lux levels are achieved in line with regulations, fittings are located correctly and meet certification requirements – we provide a comprehensive hazardous area lighting system design service.
PIR Motion Sensors
♦ Heating – T&D can provide battery room heat loss calculations to ensure the correct heaters are specified and meet ATEX certification requirements to provide adequate comfort heating to the substation.
♦ Power – T&D can specify and supply from stocks Joints & Terminations for the connection and energisation of high voltage power cables to switchgear and transformers up to 66kV.
The ATEX PIR detector is a movement sensor that detects a moving body heat (infrared) signature and provides an alarm output signal to the alarm/monitoring system accordingly within the substation battery room.
Extensive Stocks | Competitive Prices | HV Joints Terminations Connectors for GIS
The SPARTAN range of Standard & Emergency ATEX Certified light fittings manufactured by Raytec is designed for lighting hazardous areas which require high performance, high reliability, energy-efficient brilliant “White-Light” illumination using latest LED technology.
Pictured | Stocked by Thorne & Derrick, the SPARTAN WL168 Zone 2 Intelligent Emergency Linear Luminaires improve light levels on this substation battery room site. On this project, the lighting brief was to replace x 4 existing 2x58W fluorescent Zone 2 fittings. The customer originally requested 5ft LED Linear alternatives, but due to SPARTAN’s high lumen output and unique modular design – which would make any ongoing maintenance quick and easy – SPARTAN WL168 provided the ideal solution. Discuss your requirements with us.
The EXHEAT range of FAW heaters provides versatile air warming to battery rooms with 250W to 3kW ratings – the electric heaters are certified for use in hazardous areas where the explosive atmosphere is classified as a Zone 1 or 2 (IIA, IIB, IIC) gas group.
T&D are Specialist Distributors to UK Distribution Network Operators (DNO’s), NERS Registered Service Providers, ICP’s and HV Jointing Contractors of an extensive range of LV, MV & HV Jointing, Earthing, Substation & Electrical Eqpt – this includes 11kV/33kV/66kV joints, terminations and connectors for both DNO and private network applications.
Contact our UK Power Team for competitive quotations, fast delivery from stock and technical support or training on all LV-HV products.
Key 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
Specialist Suppliers of High Voltage Electrical Equipment & Cable Accessories
MTag High Voltage Detectors
The MTag series of high voltage detectors from PBwel (P&B Weir Electrical Ltd) are available from Thorne & Derrick International based in the UK, the leading Specialist Distributor of Electrical Safety Equipment.
Designed for «proving dead» on high voltage distribution system between 1kV and69 kV (voltage ranges calibrated according to IEC recommendations).
The MTag detects any nominal voltage present on a overhead line or in a substation
The MTag detector meets all the expectations and wishes expressed by users and experts in recent years.
Reliable Indication
• Detects nominal voltages of its range
• Eliminates related induced voltages
• Enhanced audible and visual signals perceptible in most conditions
Heavy Duty & Reliable Design
• Direct access to the battery
• Sealed, watertight electronic compartment
• Pole end fittings interchangeable by the user, no tools required
Available with separate proving unit.
Pbwel Mtag Voltage Detector
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, the UK Preferred Distributor for P&B Weir Electrical Ltd (PBwel), are now stocking their range of Rail Earthing Equipment with PADS Approval for use on Network Rail high voltage electrification projects. This significant and strategic stock holding is the culmination of discussions and planning to support framework contractors and construction alliances during and beyond the current CP6 plan.
Next Day Delivery 
Thorne & Derrick will be able to provide next day delivery from stock at competitive prices for the PBwel range of Operating Poles & Temporary Earthing Kits; the complete range consists of DEP Short Earth Leads, J117 Rail Clamps, Long Blue Interlocked Earths, Short-Circuiting Straps, Rail Bonds, Rail Jumper Bonds, Rail Poles, Voltage Detectors, Rail Socket and Heads, Arboriculture Equipment and Signal Sighting Targets.
“With recent industry announcements by Network Rail about their multi-billion pound Railway Upgrade Plan, which represents the largest rail investment programme since Victorian times, it is important from a business perspective that Thorne & Derrick are placed to support clients requirements from stock. We have been privileged to be suppliers to Network Rail for several decades and this extension to our PADS Approved Rail Products range is aimed to raise levels of customer service and personal safety – the product training provided by Tim Harris including support at our office and in the field has been first-class and we look forward to introducing this news to our customers in the coming weeks.”
“The PBwel Aluflex range of temporary and portable earth leads are manufactured from multi-stranded, commercially pure aluminium with an extruded PVC sheath to preserve the cable – Short Earths, DEP Earths and Jumpers & Bonds are available at any length and with clamp choices for use on 25kV OHL and substation power systems, just contact us with your requirements,” adds Chris Dodds (Sales & Marketing Manager at Thorne & Derrick).
“We had a great discussion about our future commitments and agreed sales targets at the beginning of the year for 2022 – we are now excited to implement our business development plan for the
UK rail industry. Working together with Thorne & Derrick we can design new and customised solutions for Portable Earthing and deliver via distribution standard products on an overnight service. Thorne & Derrick will support contractors and end-users via their trained Sales Team with competitive prices and stock availability of product. I will be on hand to support their team with continuous product training, either field based or online, to ensure their technical knowledge is up to date with the latest industry standards,” comments Tim Harris (Technical Sales Engineer at PBwel).
Portable & Temporary Earthing for Rail Electrification | Safe Systems of Working
The PBWel range of PADS Approved Portable Earths handle electrical and drain induced current associated with the inadvertent energisation of 25kV overhead power lines – this provides electrical protection of trackside workers and engineers carrying out maintenance, repair or construction under supervision and inspection of the project HV SAP.
Manufactured from highly conductive, commercially pure, Aluflex aluminium material the system is used during rail track possessions and electrical isolations – the Short Orange DEP (Designated Earth Point) Rail Earth is used in conjunction with operating pole sets, live line indicator and the CATU Dispensing Head MT630C.
Stocked by Thorne & Derrick
Thorne & Derrick supply an extensive range of 400V-33kV Rail Cable Accessories & Power Distribution Sytems including feeder pillars to contractors undertaking Low Voltage Power Distribution, HV Electrification & Substations, DC Traction & Networks, OLE and Track Feeder Cable Renewals – a complete range of Network Rail PADS approved track terminations, cable joints, cable repair and connection products up to 25kV, including 3M Cold Shrink, Pfisterer CONNEX and Nexans Euromold products.
Heat shrink, cold shrink, push-on and slip-over cable accessories enable the jointing, terminating and connection of medium/high voltage power cables to oil, air or gas insulated switchgear, transformers, motors and overhead lines.
Full range of Cable Pulling Equipment & Products to ensure safe and efficient of rail cables in to cable ducts and containment infrastructure including cable troughs.
Reliable & Compliant Cable Accessories for Substation, Trackside & OHL Power Supply
Contact us for a Quotation for Rail Earthing Equipment
Press Release | June 30th 2022
Thorne & Derrick, a Specialist Distributor for Ellis Patents, have delivered their largest contract to date to supply cable cleats to provide safety and reliability to high voltage power cable circuits.
The order includes a project total of over 10,000 units of their market-leader cable cleat, The Emperor. The cable cleats will be installed to provide the highest levels of short circuit protection to high voltage power cables. Following several client meetings, Thorne & Derrick were awarded the purchase contract despite market-wide challenges including raw material price volatility and supply chain strains.
This current project award is testament to our ability to utilise the in-house expertise of Ellis Patents to design project specific, bespoke solutions for customers on tight delivery schedules and builds upon recent project successes in the renewable, rail, data-centre and utility substation sectors.
“Emperor was preferred to competitors due to the products established track record and its evidenced compliance to the rigorous IEC 61914: 2015 standard. The ability to demonstrate product performance in similar harsh operating environments with past project references was critical. Ellis Patents have an international reputation to commit and meet customer delivery requirements – trust in the customer-supplier relationship was central to securing the business. We are now working with Ellis on several custom engineered cable clamps and support solutions – the commercial and technical support by Ellis Patents to Thorne & Derrick was outstanding and instrumental in securing this prestigious project order for both our companies,” comments Chris Dodds (Sales & Marketing Manager at Thorne & Derrick.
The Emperor is a heavy duty compact stainless steel cable cleat designed, developed, tested and manufactured in accordance with IEC 61914. The cleat is available in an extensive range of sizes with range taking ability to suit cables installed to containment in single or trefoil formation. The frame of the cleat is manufactured from corrosion resistant grade 316L stainless steel, the cable is supported by a liner manufactured form a low smoke zero halogen (LSOH) material. The closure fixings are manufactured from grade A4-70 stainless steel. The Emperor can be fixed to the supporting structure by either two M10 fixings or one M12 fixing. Non standard cleat designs can be supplied upon request.
ES Single Range | 32-150mm diameters with short-circuit test levels to 235kA at 225mm cleat spacings
ER Trefoil Range | 19-128mm diameters with short-circuit test levels to 195kA at 300mm cleat spacings
Ellis Patents are an outstanding manufacturer innovator of products to drive down life cycle costs, including their Twist-Foot design of cable cleats which is typically 3 times faster to install than using conventional fixings.
Jonny Hewitt from Thorne & Derrick with Noman Shabir from Ellis Patents at the Dogger Bank – Meet The Buyer Event.
Key Product Categories: Connectors, Joints & Terminations MV HV | Cable Preparation & Jointing Tools | Duct Seals | Cable Transits | Cable Cleats | Cable Glands | Electrical Safety | Arc Flash Clothing & Protection | Cable Pulling | Earthing & Lightning Protection | Feeder Pillars
Thorne & Derrick distribute the most extensive range of MV HV Medium & High Voltage Cable Joints, Terminations & Connectors from manufacturers including 3M, Prysmian, Nexans Euromold, Elastimold, Pfisterer CONNEX & SEANEX.
uploaded by Chris Dodds | Sales & Marketing Manager at Thorne & Derrick
Thorne & Derrick are privileged to partner with EDS HV Group and support career opportunities within the Wind Industry via their Talent Pool.
Are you an existing Senior Authorised Person (SAP) within the wind industry?
Are you an existing HV High Voltage SAP working in a similar industry looking to make a career move into renewables ?
If so, check out the EDS HV SAP Talent Pool and register your details below today – this is an opportunity to join one of the fastest growing businesses servicing a wide range of clients within the renewable power industry.
SAP Role Vacancies Onshore/Offshore Wind |
|
| Reference | MAY20226602 |
| Expiry date: | 19:04, Wed, 15th Jun 2022 |
| Location: | United Kingdom |
| Salary: | Competitive |
| Benefits: | Competitive |
| Duration: | Various Contracts |
EDS HV Group is a leading authority in the design, installation, operation, maintenance, and repair of high voltage windfarms. Mainly operating in the UK and Europe, EDS has been serving renewables for over a decade and impacting every stage of the wind farm lifecycle.
Due to the growth of EDS they are looking for experienced staff with specific HV SAP experience, with suitable qualifications for a role within the wind industry.
EDS have opportunities across several geographical areas including UK sites, Europe, Taiwan and Japanese sites.
EDS is an innovative and fast-growing organisation with highly skilled teams that enable them to deliver solutions to the most demanding operational and technical challenges faced by their Customers.
EDS HV Group SAP team members will have the following:
Essential: An existing SAP (could be 400/275/132 or 66kV), with the requirement to become authorised under the EDS HV Safety rules and customer site safety rules
If you have experience in the above specialism then EDS want to hear from you!!
Complete your application and submit your CV to them now.
Please note this is a Talent Pool, therefore you will only be contacted by EDS when a role becomes available and if your CV is suitable.
If you do see a specific role advertised on the EDS careers site please do apply for that in addition to your CV being in this Talent Pool.
Specialist Distributors of High Voltage Jointing & Electrical Safety Equipment
Thorne & Derrick International are Specialist Suppliers to the UK and international Offshore Wind Industry of products to provide safe and reliable LV HV Electrical Cable Termination, Jointing, Installation & Power Systems up to 66kV.
We are based in North-East England, recognised as a key strategic location to service the offshore renewables energy market in the UK, from the North Sea to the Nordics – our Exports Division support international offshore wind power projects from USA to China.
Key Product Categories: Connectors, Joints & Terminations MV HV | Cable Preparation & Jointing Tools | Duct Seals | Cable Transits | Cable Cleats | Cable Glands | Electrical Safety | Arc Flash Clothing & Protection | Cable Pulling | Earthing & Lightning Protection | Feeder Pillars
Thorne & Derrick distribute the most extensive range of MV HV Medium & High Voltage Cable Joints, Terminations & Connectors from manufacturers including 3M, Prysmian, Nexans Euromold, Elastimold, Pfisterer CONNEX & SEANEX.
Published 15 Oct 2025
Testimonial Organiser | EA Technology Event | Industrial Forum 2025 Title | Keeping Electrical Switchgear Safe Date | 14th October Location | Chester Racecourse By | Chris Dodds (Sales & Marketing Manager at Thorne & Derrick | Co-Exhibitor with...
Published 18 Sep 2025
Thorne & Derrick International, the UK’s leading Specialist Distributor of LV HV Cable Accessories, Tooling & Hazardous Area Electrical Equipment, are celebrating 40 years of supplying products and solutions that ensure the safety and reliability of industrial heating, lighting...
