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3M Cold Shrink vs Heat Shrink

A series of How-To videos for repairing, jointing and terminating cables using 3M Cold Shrink & Scotchcast products.

Cold Shrink

This video by 3M Electrical shows the benefits of using 3M Cold Shrink compared to heat shrink cable accessories to insulate, joint, repair and terminate cables.

3M cold shrink tubes utilise a unique cold applied delivery system which is designed to make cable jointing, insulating, termination and abandonment as simple as possible without any of the inherent workplace risks associated with “hot-working” and using naked flames to activate heat shrink type cable accessories.

Cold shrink reduces the risk of damaging XLPE cable insulation caused by scorching or over-heating of the cable by the jointer. No cooling time is required before energising cables.

Cold Shrink Benefits

Installation is fast and an easy one-step installation process:

• Labour Savings – enables installation of cable accessory in 1/3 of the time or less compared to heat shrink equivalents
• Tooling – no special heating tools or “hot-work” work permits required
• Compact – smooth profile cold shrink limits volume displacement on cable tray where congregated cable joints are located
• Outdoor – resistant to weathering for continued outdoor service in environmental and exposed locations
• User Friendly – easy to learn and train with less installation steps
• More Cold Shrink Videos | Cable Abandonment | Cable Terminations MV HV

➡ See How To Use Cold Shrink Tubes.  

3M Tubes – available in EPDM Rubber or Silicone

Depending on the application cold shrink is available manufactured in EPDM Rubber or Silicone – contact us to discuss your application.

Cold Shrink creates a static and stable cable seal that does not expand or contract with the cable under thermal cycling of LV-HV cables, potentially leading to the creation of voids between the cable accessory and the cable which could lead to a joint or termination failure.

Cold Shrink – invented by 3M over 40 years ago and now the preferred technology for heat-free jointing, terminating, sealing and abandonment of LV HV cables

We hope you find this video informative and educational, contact T&D for technical support, quotations and stock availability for 3M Cold Shrink.

Trust Cold Shrink

• Low Cable Failure Rates*:
  – 0.067% for Cold Shrink Cable Joints & Cable Splices
  – 0.022% for Cold Shrink Terminations

* Data based upon U.S. failure data of U.S. manufactured 3M Cold Shrink Medium Voltage Cable Accessories between 2009 and 2012.

3M

Should you require support about selecting the correct 3M Cold Shrink product range for use with low, medium or high voltage cables please contact us – a complete range of Cold Shrink cable joints and terminations is available for MV-HV cables, including 11kV/33kV.

➡ Visit 3M Electrical for further information about 3M cable joints, terminations, tapes and insulation to seal, repair, splice and connect LV MV HV cables.

Cold Shrink | Joint | Terminate | Seal | Repair | Splice | LV MV HV Cables | 3M

• 3M Electrical Products Stocked By Thorne & Derrick International 

Selecting MV Bushings & Cable Connectors For Use With Schneider Switchgear (Medium Voltage)

Schneider Gas Insulated (SF6) Switchgear, RMU’s & MV Medium Voltage Electrical Equipment

• Uploaded by Chris Dodds – reading time 8 minutes

Switchgear Bushings & Cable Connectors

The following information has been provided to enable to correct selection and specification of MV Bushings and Separable Connectors used to connect and terminate medium/high voltage power cables into Schneider RM6 gas insulated switchgear and Ring Main Units (RMU) up to 24kV.

General

• The profiles, contacts and dimensions of the Schneider RM6 connection interfaces are defined by the IEC 60137 standard
• 100% of the epoxy resin interfaces undergo dielectric testing at power frequency and partial discharge tests
• Insulated connectors must be used in order to guarantee the dielectric performance

Appropriateness For Use

Types of Connection Interface

The bushings carry the electrical current from the outside to the inside of the MV switchgear enclosure, which is filled with SF6 gas, ensuring insulation between the live conductors and the frame for MV power distribution.

There are 3 types of MV bushing, which are defined by their short-time withstand current:

• Type A Interface Bushing: 200 A: 12.5 kA 1 s and 31.5 kA peak (plug-in)
• Type B Interface Bushing: 400 A: 16 kA 1 s and 40 kA peak (plug-in)
• Type C Interface Bushing: 630 A: 25 kA 1 s, 21 kA 3 s + 62.5 kA peak (disconnectable M16)

➡ For further information on Euromold Connectors for all other Interface Bushings up to 66kV please see the following information:

The Euromold brand of MV Cable Connectors manufactured by Nexans for 11kV 33kV 66kV connection of medium/high voltage power cables into gas insulated electrical equipment.

How To Define The Cable Connectors Interface

The connection interfaces depend on specific criteria, such as:

Installation

• Current rating of the connected equipment: 200, 400, 630 A
• Short-time withstand current for 12.5 kA, 16 kA, 25 kA switch and circuit breaker functions
• For the fuse-switch combination function, as the short-circuit current is limited by the fuse, the connection interface will be of type A (200 A)
• Minimum phase expansion length
• Connection type: plug in: multicontact ring, disconnectable: bolted
• Output position: straight or elbow connectors

MV Medium Voltage Cable

• Specified voltage: of the cable, of the network
• Type of conductor: aluminium or copper
• Cross section in mm²
• Primary insulation diameter
• Cable composition: single-core or 3-core
• Insulation type: dry, paper impregnated (non-draining type)
• Type of screen: copper tape or copper wire screen
• Armour: SWA (steel wire armour), AWA (aluminium wire armour) or unarmoured (copper wire screened)

Gas Insulated Switchgear – Schneider RM6

1. Stainless steel tank filled with SF6 gas, sealed for life and containing the medium voltage (MV) busbar and all live switching components such as the switch-disconnector, earthing switch, the fuse switch combination or the MV circuit breaker
2. One of the five cable compartments with interfaces to connect to the network or medium voltage transformer
3. User interface with single line diagram, actuators and LV components
4. Manual or motorised operating mechanism compartments
5. Earthing circuit with visible earthing contacts

Type A Bushing – Directed field plug-in connector

Dry single-core cable

➡ Further information link: Elastimold Connectors

Type A/M8 bushing – Non-directed field disconnectable connector (*)

Dry single and 3-core cable

(*) 520 mm plinth must be used

Type B bushing Directed field plug-in connector

Dry single-core cable

Type C bushing – Directed field disconnectable connector

Dry single-core cable

Non-directed field disconnectable connector

Dry single and three-core cable

Non-directed field disconnectable connector

Single-core cable, paper impregnated, non-draining type

Non-directed field disconnectable connector

Three-core cable, paper impregnated, non-draining type

Disconnectable Connector Single-core Dry Cable &

MV Medium Voltage Lightning Arrestor

See How Thorne & Derrick & Nexans Euromold can support your MV Bushings & Connectors requirements

Thorne & Derrick International

Since 1985 Thorne & Derrick based in the UK have been specialist distributors of LV, MV & HV Cable Installation, Jointing, Substation, Arc Flash Clothing & Electrical Safety Equipment – customers include UK and worldwide contractors, specifiers, traders and end-users involved in medium and high voltage cable installations, cable jointing, substation, overhead line and electrical construction.

We are specialist stockists and distributors of 11kV-33kV Cable Joints, Terminations & Connectors from manufacturers including 3M, Pfisterer, Prysmian and Nexans Euromold in a selection of cable jointing technologies including push-on, heat shrink and cold shrink joints and cold shrink terminations.

MV HV | Medium & High Voltage Power Products, Tools, Cables & Electrical Equipment

Interface A Connectors & Bushings From Nexans Euromold

Nexans | Connectors | Joints | Terminations | 11kV 33kV 66kV MV HV Cables – Interface A

Medium Voltage Separable Connectors & Bushings

Euromold Connectors

Up To 24kV 250Amps

Thorne & Derrick International distribute the complete range of Nexans Euromold Connectors for all types of medium/high voltage electrical bushings including Interface A according to CENELEC EN 50180 and 50181. Complete supporting range of medium/high voltage cable accessories including Euromold elbow connectors, straight connectors, straight plugs and surge arresters are available for bushing Interface A equipment.

➡ See Euromold 158LR Elbow Connector and Euromold 152SR Straight Connector

Interface A Connectors

➡ For further information about Euromold Connectors for all other Interface Bushings please see the following information:

Switchgear ♦ Transformers ♦ Motors ♦ Joint ♦ Terminate ♦ Connect ♦ Cables ♦ MV HV Bushings ♦ 11kV 33kV Medium & High Voltage

Thorne & Derrick International

11kV 33kV Terminations

T&D are Main UK Distributors for Nexans Power Cable Accessories – this includes heat shrink and cold shrink cable joints and terminations and the Euromold range of screened separable connectors extensively installed to terminate MV-HV power cables.

T&D 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 

Portable Earthing Kits Installed With Insulating Sticks To High Voltage Overhead Lines

• Images Courtesy: Murray Jones (Specialist Trainer, Transmission Lines & Rigging)
• Application: Portable Earthing Overhead Line Distribution Networks
• Voltage: 275kV Extra High Voltage (EHV) 
• Uploaded by Chris Dodds – reading time 3 minutes

Portable Earthing

In this high-wire act the overhead linesmen are shown using Portable Earthing Kits on 275kV overhead power distribution and transmission lines – the portable earths are installed and connected using Insulating Sticks.

♦ See Portable Earthing – Short Circuiting Kits For HV Substations & Overhead Lines

The bottom phases are earthed using high voltage portable earthing kits by the Linesmen.

CATU Electrical – High Voltage Electrical Safety Equipment

Using insulating sticks the portable earthing kits are positioned and clamped to the overhead line by the Linesmen.

Insulating Matting | Insulating Gloves | Substation Safety | Arc Flash Clothing  MV HV EHV Electrical Safety Equipment Suppliers & Stockists

Electrical Safety For Overhead Lines & Substations

Thorne & Derrick International are the UK’s leading stockist and supplier of the CATU Electrical range of Electrical Safety Equipment – protecting utility workers including jointers, splicers and linesmen exposed to the risk of electrocution and arc flash hazards.

A complete range of HV Sticks are available for use on 33kV/40kV, 66kV/90kV and 275/400kV underground cables and overhead lines with a selection of short circuiting and portable earthing kits and associated high voltage earth clamps for substation busbars or line conductors. Insulating sticks are available as telescopic and extendable suitable for outdoor use or supplied as fixed length sticks.

The following tables provides an overview of Portable Earthing Kits available from CATU Electrical, The Electrical Safety Specialists – comprehensive range of earthing clamps are available for MV-HV substation, power cables and overhead conductors.

♦ Portable earthing kits used with CATU CF-5-40-E insulating stick (up to 40kV) – generally used to provide short circuiting and earthing on power systems operating at 11kV/33kV.

Portable Earthing & Short Circuiting Kits

♦ Portable earthing kits used with CATU CE-4-21-C insulating stick (up to 90kV) – – generally used to provide short circuiting and earthing on power systems up to 66kV.

All following images courtesy: Murray Jones.

Tower transfer to allow for structural work to high voltage overhead lines

Hanging 600mm rollers to tension string OPGW using existing earth wire as the draw wire

400kV live line insulator wash

Overhead Line Equipment Distributed by Thorne & Derrick

Euromold Connectors – Termination Of 33kV MV Prysmian Power Cables Using Nexans Elbows

• Application: Connection & Termination Of 33kV Cable Into MV Siemens GIS
• Cable Connector Type: Nexans Euromold Interface C Bushing Connector
• Cable Connector Part Code: Euromold (M484TB/G-32-95.240UN5+KIT)
• Cable Type & Manufacturer: Prysmian 33kV XLPE Single Core 
• Cable Jointer: Daniel Croft
• by Chris Dodds T&D – estimated reading time 5 minutes

Dan is currently IAC Cable Installation Engineer Nordsee Cluster for Nordsee Two GmbH

Euromold Connectors

Today, we welcome Dan Croft onto our Jointers Blog to demonstrate the skill level and competency required to terminate 33kV cables into gas insulated switchgear manufactured by Siemens using Euromold Connectors.

The medium voltage power cable manufactured by Prysmian is expertly prepared by the 33kV Competent Cable Jointer using precision engineered and professional cable jointing tools – the 33kV Prysmian cable was stripped and prepared using the following;

Cable Jointing Tools

• Alroc MF2-60 Outer Cable Sheath Stripping & XLPE Removal Tool
• Alroc CWB18-60 Bonded Semicon Removal Tool
• Alroc AR25 Inner Semicon Removal Tool
• Boddingtons 244240 XLPE Insulation Chamfering Tool
• Kevlar String

Nexans EXPERT MV Cable Jointers Tool Kits

Installing 33kV Connectors

Daniel explains the Euromold connector installation, “the 33kV copper earth screen is bonded to the outer sheath so a window needs to be taken out with Kevlar string, a bit of heat and a tool such as a flat head screwdriver. Used very carefully and precisely in order to remove the window without damaging the screen underneath. Also, all MV cable preparation work such as stripping of bonded screen and XLPE insulation removal must be conducted to the highest possible standard – this includes sanding and polishing of the XLPE insulation layer to ensure there is a “super smooth” and unblemished surface. This is achieved by the cable jointer using precision shaving techniques then sanding (with 240,320 and 400 grit sandpaper sheets). Finally, the 33kV cable insulation is polished with super fine paper and carefully heated creating a surface as smooth as glass. The 33kV cable is then ready to terminate using the Euromold connector type dependent upon the medium or high voltage equipment Bushing Interface type.”

➡ Euromold connectors are available in Interface A-F specifications to terminate MV-HV cables into switchgear, transformers and substations including up to 66kV connections.

33kV Cable

33kV Cable Specification. The medium/high voltage power cable specification is 33kV single core XLPE insulation with 240sqmm aluminium conductor and copper tape screen – the semicon screen layer is fully bonded to XLPE. Also the cable sheath has an additional fully bonded semicon layer. The cable sheath has a semi-conductive later bonded to it which needs removing for electrical separation between the copper earth tape and outer sheath.

33kV Connectors. 33kV cables are terminated using Nexans Euromold Connectors and connected into the electrical equipment to create a “touch-safe” screened MV cable termination into the gas insulated switchgear.

Flashguard Installed. Arc free and arc flash protection solution for MV Power Distribution Electrical Equipment – the physical barrier stops the MV-HV connectors or terminations becoming free from the switchgear or transformer bushing in the unlikely event of a fault.

Thorne & Derrick International

Should you require any assistance with the selection or specification of Prysmian cable joints please do not hesitate to contact us.

T&D distribute the most extensive range of MV & HV Cable Joints & Terminations, Cable Installation Accessories & Cable Pulling Equipment – we service UK and international clients working on underground cables, overhead lines, substation earthing and electrical construction at LV, 11kV, 33kV and EHV transmission and distribution voltages.

• Key Products: MV-HV Cable Joints & Terminations, Cable Cleats, Duct Seals, Cable Transits, Underground Cable Protection, Cable Jointing Tools, Feeder Pillars, Cable Ducting, Earth Tapes, Electrical Safety, Cable Glands, Arc Flash Protection & Fusegear.

• Distributors for: 3M, ABB, Alroc, Band-It, Catu, Cembre, Centriforce, CMP, Elastimold, Ellis Patents, Emtelle, Furse, Lucy Zodion, Nexans Euromold, Pfisterer, Polypipe, Prysmian, Roxtec.

LV – Low Voltage Cable Joints, Glands, Cleats, Lugs & Accessories (1000 Volts)

MV HV – Medium & High Voltage Cable Joints, Terminations & Connectors (11kV 33kV EHV)

Cable Laying – Underground Cable Covers, Ducting, Seals & Cable Pulling Equipment