uploaded by Chris Dodds - Thorne & Derrick Sales & Marketing Manager
Working closely with HV and EHV cable manufacturers Thorne & Derrick have designed and developed a standard range of cable heating jackets for straightening and relaxation of high voltage cables prior to installing MV HV Joints, Terminations & Connectors – T&D supply a complete HV cable straightening set focusing on safe, exact and consistent heating of high voltage cables with adjustable temperatures up to 100°C.
The unique cable straightener solution with extension pieces gives the HV jointer the most flexible cable heating solution to cover several different cable dimensions with fully homogeneous load density for XLPE insulated cables.
Cable straighteners are used to heat voltage class MV HV cables: 33kV 66kV 132kV 275kV
The following table provides technical data to cover the performance and application of cable heater blankets for MV HV cables – please note this is for standard cable straightening applications up to 132kV. T&D working with MV HV cable manufacturers and installers can provide customised cable heating solutions for all types of polymeric (XLPE) type cables.
The cable heaters feature an in built overtemperature switch at 110°C.
| Operating Voltage | 220-240VAC or 110-120VAC |
| Cable Heating Range | Ø70-190 mm or Ø40-69 mm (Outside Diameter) |
| Cable Heating Temp. | 95°C (adjustable setpoint, PID/rampable by time control) |
| Insulation Thickness | 25mm |
| Cables | 5m power supply, 5m cable from controller to cable heating jacket |
| RCD | 30mA, Type A |
| IP Rating | IP44 |
| Cable Heating Voltages | 33kV 66kV 132kV 275kV |
The following table includes the standard Cable Heating Jackets – should you require any specification support or technical advice to select the correct cable straightening jackets please do not hesitate to contact us.
| Order Code | Operating Voltage | Cable Diameter | Cable Heater Length |
| CSR 70-115 Cable Heater Blanket up to 190mm Diameter | |||
| Single Set CSR 70-115/1-1500-230 | 220-240VAC | 70-115 | 1500mm |
| Double Set CSR 70-115/2-1500-230 | 220-240VAC | 70-115 | 1500mm |
| Extension CSR EP25-1500-230 | 220-240VAC | – | 1500mm |
| Single Set CSR 70-115/1-2000-230 | 220-240VAC | 70-115 | 2000mm |
| Double Set CSR 70-115/2-2000-230 | 220-240VAC | 70-115 | 2000mm |
| Extension CSR EP25-2000-230 | 220-240VAC | – | 2000mm |
| Single Set CSR 70-115/1-1500-115 | 110-120VAC | 70-115 | 1500mm |
| Double Set CSR 70-115/2-1500-115 | 110-120VAC | 70-115 | 1500mm |
| Extension CSR EP25-1500-115 | 110-120VAC | – | 1500mm |
| CSR 40-69 Cable Heater Blanket up to 69mm Diameter | |||
| Single Set CSR 40-69/1-2000-230 | 220-240VAC | 40-69 | 2000mm |
| Double Set CSR 40-69/2-2000-230 | 220-240VAC | 40-69 | 2000mm |
| Cable Straightening Aluminum Profile | – | – | – |
| CSR SP2000 | – | – | 2000mm |
Here is shown the Pfisterer range of cable heating blankets used to pre-heat and straighten medium/high voltage XLPE insulated power cables prior to termination with their pluggable CONNEX range of inner cone terminations.
The following information is published from the Western Power Distribution company directive CA3C/2 Relating to General Requirements for 33kV Cable Jointing and specifically to the sub-section Heat Straightening of 33kV High Voltage Cables.
With dry designs of medium/high voltage polymeric cable after the removal of the oversheath and metallic sheath, the polymeric XLPE cable has a tendency to bend. This can give rise to problems associated with the fitting of the cable terminations or straight joints. Because of this there is a need for a heat treatment process to be applied to each cable core to relieve the mechanical stresses that are locked into the cable insulation.
With the wet designs of polymeric cable the polymeric cable has a tendency to bend, even after being set into their final position. This can give rise to problems associated with the fitting of the cable terminations or straight joints. Because of this there is a need for the heat treatment process to be applied to the core to relieve the mechanical stress that is locked into the cable insulation
Apply the tube, fitted with the heater tape and thermocouple, over the cable end and onto the PVC packing. Ensure that the thermocouple is not directly under the heater tape. Wrap the complete assembly with a thermal blanket.
Heating 33kV Cables Figures 1
Switch on the controller and bring the temperature of the cable up to 90°C, once the cable has reached the required temperature the heating time is determined by the cable size.
Given below: –
4 hours for conductor sizes up to and including 500sqmm
6 hours for conductor cross sections above 630sqmm and up to 1600sqmm
After the requisite time, switch off. Remove the cable heating blanket, heater tube complete with heater tape, thermocouple and PVC packing. Wearing appropriate gloves carefully straighten the cable into the correct position by hand.
Heating 33kV Cables Figures 2
Clamp the cable into position on a V shaped angle irons or channel irons and allow the cable to cool for a minimum of two hours, insuring the angle iron or channel irons stay in the correct position during the cooling process.
Jointers depend on 132kV cable heating jackets and blankets to straighten EHV power cables prior to installing Pfisterer CONNEX type inner cone cable terminations into high voltage gas insulated switchgear and susbtations.
➡ Drum Heating & Cable Straightening Jackets For 132kV Extra High Voltage Cable Terminations
Thorne & Derrick are stockists of market-leading manufacturers of Cold Shrink, cold applied, heat shrink and EPDM type joints, terminations and connectors up to 66kV.
MV HV cable heaters are designed to provide consistent surface heating to the cables of XLPE insulated type – when cables are pulled from the coiled state on a cable drum they have a tendency to naturally attempt to recoil. The heating process provides linearity of 33kV/66kV/132kV cables to enable optimum installation of cable joints, terminations or connectors in Cold Shrink, heat shrink or EPDM type rubber technology.
Partial Discharge Measurement & Analysis for Power Cables
uploaded by Chris Dodds | Thorne & Derrick Sales Marketing Manager
MPD 800 universal partial discharge (PD) measurement and analysis system, the next generation of the widely-used and innovative MPD PD testing technology from OMICRON.
Advanced hardware and software features ensure highly-sensitive single- or multi-channel PD measurements for reliable, industry-standard PD testing on power transformers, rotating electrical machines (motors and generators), power cables, instrument transformers, switchgear, industrial drives and electrical components.
The configurable, multi-language MPD 800 software allows you to select only the PD measurement and analysis features you need for specific PD tests and individualised reporting. Powerful noise suppression and PD source separation techniques ensure reliable PD analysis in areas with high levels of interference.
The MPD 800 PD testing system accurately detects and localizes insulation defects and helps you to assess the risk of failure in electrical equipment during research and development, factory testing, site acceptance testing (commissioning), as well as in-service troubleshooting for effective maintenance planning.
“The MPD software guides you through the entire PD measurement process on power cables, and it provides you with detailed analysis and individualized reporting.”
➡ Featured with the kind permission of David Brazier (Area Sales Manager & Site Manager at Omicron Electronics)
♦ MPD 800 Universal Partial Discharge Measurement & Analysis System – Brochure
 Meets industry standards. The MPD 800 measures partial discharge in compliance with the IEC 60270 standard to ensure the reliable detection of PD activity in high-voltage power cables. |
 Reliable noise filtering. The MPD 800 provides you with a free choice of measurement frequency and bandwidths to maximize measurement sensitivity in environments with high interference. |
 Advanced analysis tools. MPD 800 uses advanced graphical tools, such as 3PARD (3-Phase Amplitude Relation Diagram), to separate multiple partial discharge sources for reliable fault detection. |
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
Providing Arc-Flash Protection With Remote Circuit Breaker Racking Devices MV HV
Press Release: Chris Dodds - Sales & Marketing Manager with Thorne & Derrick International
Thorne & Derrick International, the Specialist Distributors of LV HV Jointing, Earthing, Substation & Electrical Eqpt have signed a MOU to undertake the Sales Distribution & Marketing of the CBS ArcSafe range of Remote Circuit Breaker Racking products – this product range provides arc-flash protection with remote circuit breaker racking devices for LV MV HV power systems including high-risk aging assets.
The CBS ArcSafe range of remote racking products covers 95% of global switchgear market applications – we will be servicing the UK market with site training, demonstration and visits.
This UK agreement augments our Electrical Safety product range to ensure the safe installation, operation and maintenance of LV MV HV substations, underground cables and overhead line conductors from 600V up to 420kV.
CBS ArcSafe offers the electrical industry’s largest inventory of remote racking and switching solutions for switchgear – the systems operate without modification to existing electrical equipment and allow authorised technicians and personnel to operate equipment from a safe distance of up to 300 feet.
CBS ArcSafe | the highest quality remote operation equipment for protection of people’s lives and plant operations against arc flash hazards.
Thorne & Derrick are national distributors of LV, MV & HV Cable Installation, Jointing, Substation & Electrical Equipment – servicing businesses involved in cabling, jointing, substation, earthing, overhead line and electrical construction at LV, 11kV, 33kV, 66kV and EHV. Supplying a complete range of power cable accessories to support the installation and maintenance of low/medium and high voltage power systems.
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
uploaded by Chris Dodds - Sales & Marketing Manager with Thorne & Derrick International
Thorne & Derrick, the Specialist Distributor of LV HV Jointing, Earthing, Substation & Electrical Eqpt have supplied a cable winch requirement to a leading provider of offshore power distribution to the renewable and oil/gas sectors.
The refurbished and customised 5 tonne cable winch was customised to enable the pull and installation of medium/high voltage power cables – the winch was delivered
within 2 weeks from receipt of client order. The cable winch enabled the installation of cable runs up to 120 metres from the variable frequency drive (VFD) to the compressor junction box which goes from underground cable trench to above ground and onto the cable containment ladder racking system.
The cable winch modification was based on the standard SEB TW5000 version with additional cable tension dynamometer – the dynamometer continuously checks the cable pulling tension to ensure the forces do not exceed the recommended guidelines.
Additional features Pre-Set Load Function, Load Display, Test Certification & Load Cell.
Press Release | Thorne & Derrick Appointed Approved Stockist for UK Leading Cable Pulling Equipment Manufacturer
Thorne & Derrick distribute an extensive range of Cable Pulling & Laying Equipment to enable the safe installation of fibre and copper cables within the telecommunications industry. Safely installed cables reduces operational and maintenance requirements to the network and reduced service interruption to telecom cables, wires, ducts, cabinets and exchanges – products include cable spiking tools, conduit rods, cable lubricant, cable socks and rollers.
Product Application & Solutions | Jointing & Terminating LV MV HV Cables
Olex Cable Joints
➡ Shrink Polymer Systems heatshrink cable joints and terminations suit all types of MV-HV electrical cables (single or multi-core) with or without armour or lead sheaths – zero halogen and fire resistant cable joints are also available.
Olex Cable Joints
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...
