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Sealing Cables, Switch Hall & Grid Transformer Bases On 132kV Wind Farm

• Product Category: Duct Seals
• Application:Sealing Extra High Voltage Cables & Ducts Against Water, Gas & Fire
• Voltage: High Voltage 132kV
• Sector: Renewable Energy (Wind)
• Product Installed: Filoseal+, Filoseal+HD and Filoseal+ HD Fire Cable Duct Sealing System
• Project Information: All 3 types of Filoseal cable duct seal systems were required; original Filoseal+ with foam backing, newer Filoseal+HD for heavier cables and the newest seal type Filoseal+HD FIRE which adds BS EN1366 Part 3 with up to 4 hours of fire protection. All four cable duct seals were installed according to instructions whilst special guidance and tips were given on site by the manufacturer
• See Also: Cable Transits

Duct Seals

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.

♦ 132kV Surge Arresters | 132kV Link Box Stockists

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

Heat Shrink Cable Terminations – Potential Critical Medium Voltage Power Outage

• uploaded by Chris Dodds - Thorne & Derrick Sales & Marketing Manager

Medium Voltage Terminations

A Cause For Concern

MV HV Application: Electric Arc Furnace Power 48 MVA 13.8kV

The heat shrink cable terminations are connecting the 13.8kV high voltage power cable to Siemens Circuit Breakers (3AH2 Type) with vacuum ruptors located in the MV-HV control room – notice the bleeding mastic melting from the cable terminations suggesting overheating potentially caused by sub-standard jointing at the semicon screen cut of the MV-HV cable. The client has used suitable electrical cable cleaners to remove the mastic however the situation is recurring and the client is extremely concerned about the potential risk of a critical power outage caused by eventual failure of the cable in the furnace vacuum circuit breaker.

Although no diagnostic results are available for this application the information is posted to highlight the potential shortcomings with respect to cable preparation prior to the installation of the cable terminations – medium voltage terminations and cable joints should only ever be installed by Trained & Competent Cable Jointers using the correct cable preparation tools.

“The bulge at the bottom of the cable termination will be the red mastic applied over the constant force spring. Definitely too much yellow mastic over the semi-conductive screen ends (large bulge), really no need to fit that much by the cable jointer. I witnessed some testing some years ago in the Elcon HV lab (see Elcon listed on the anti-track heat shrink tube) and the jointer applied less than half that was in the termination kit, just enough to fill the small semicon screen cut void. But the partial discharge (PD) reading was near zero. Apply too much and the PD readings were far above acceptable test standards but not enough to cause this heating issue. Would have liked to have seen some more pictures further out and different angles. But with the red mastic flowing and the discolouration of the heat shrink tubes, a lot of heat there and could be an earthing issue and high circulating currents present as a result.” Richard Poulter, Shrink Polymer Systems.

Medium Voltage Electrical Equipment

Siemens 3AH2/3AH4 Vacuum Circuit-Breakers

In the voltage range up to 24kV, up to 60,000 operating cycles are possible with Siemens 3AH2 circuit-breakers. Minimum maintenance work, such as greasing of operating mechanisms after 10,000 operating cycles and replacement of vacuum interrupters after 30,000 operating cycles, preserves the reliability of these circuit-breakers throughout their entire service life – despite high mechanical stress.

Siemens vacuum circuit-breaker type 3AH4 up to 33kV/36kV is designed for extremely high numbers of operating cycles – the circuit-breaker controls 120,000 operating cycles. 3AH4 circuit-breakers master this extreme stress throughout their entire service life.

Greasing of the operating mechanism is not required until 10,000 operating cycles have been reached – vacuum interrupters just have to be replaced after 30,000 operating cycles.

Note: Due to low quantities, the 3AH2 medium voltage vacuum circuit-breaker will be discontinued by December 31, 2007. As of January 1, 2008, Siemens will offer this circuit-breaker type for another 10 years for replacement purposes only.

➡ See also: T-Plug Cable Connectors – 33kV Medium Voltage Switchgear Connectors For Siemens NXPLUS C

MV Medium Voltage Jointing, Terminating & Electrical Equipment Specialists

Medium Voltage Product Categories

Thorne & Derrick are specialist distributors of Medium Voltage Cable Accessories, Copper Earthing Products and Electrical Equipment for use with 11kV/33kV underground cables and overhead lines – including an extensive range of heat shrink, cold shrink joints, terminations and connectors for LV MV HV cables.

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 

3M | Nexans Euromold | Pfisterer | MV HV Joints Terminations Connectors

Alroc ASCR1 Jointers Tool Used To Remove Bonded Semicon From MV HV Cables

• uploaded by Chris Dodds T&D Sales & Marketing Manager 

The Video kindly contributed by Watkins & Jacomb CPC shows the cable jointer using Alroc tools to effectively strip and remove the bonded semicon screen from the XLPE insulated 11kV cable prior to installing heat shrink cable terminations.

Alroc ASC R1 | ASC R2 Tool

The Alroc ASC cable tool removes the bonded semi-conductor from MV and HV cables and creates a chamfer on the semi-conductor layer to facilitate the installation of joint, termination or connector.

➡ View the complete range of cable jointing tools for the removing of sheath, insulation and semicon screen from medium/high/extra high voltage power cables.

Cable Tools

Video Contributed By: Watkins and Jacomb Construction Power & Consultancy. WJCPC are specialist LV HV Cable Termination & Jointing contractors with over 20 years experience in the High Voltage Electrical Industry covering the utilities, renewable energy, rail, data centre and general industry sectors – UKPN competent for LV & HV Termination and Jointing Of Cables, Confined Spaces, Substation Entry and Cable Fault Finding.

See also  ➡

• HV Cable Terminations – A Report Into 11kV Heat Shrink Termination Failure
• 11kV Triplex Cables Terminated Using Heat Shrink Cable Terminations
• Cutting 11kV Cables Using Cembre Battery Cable Cutting Tools

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 

MV HV Cables 11kV 33kV – Cable Joints, Terminations & Connections

Rat & Rodent Resistant Cable Duct Seals For LV MV HV Cables & Substations

• by Chris Dodds T&D - estimated reading time 3 minutes

Sealing Ducts

Wildlife induced power outages are increasingly caused by the invasion of rats and rodents into medium/high voltage electricity substations via unsealed and inadequately sealed cable ducts and then gnawing electricity power cables.

Filoform FiloSeal+HD is a duct sealing system that is able to seal large heavy armoured power (multicore XLPE SWA) and high voltage cables in ducts, bore holes or cable transit frames – providing a strong support system using hexagonal tubes building a re-enterable seal with honeycomb structure.

The duct seal system is extensively approved and used by UK utilities, DNO’s and their preferred ICP (Independent Connection Provider) to protect electrical assets and cables within substations typically operating at 11kV, 33kV, 66kV and up to 132kV from rat attack.

The cable duct seal kits have been extensively tested against pressure, pulling forces, chemicals, gases and hydrocarbons for adequate sealing of LV-HV cables against the danger of flood (water ingress) or gas migration.

Recently, testing was carried out to establish the ability of the duct seal system to resist, repel or prevent rat attack through cable ducts into electricity substations and the following post provides information about the test and their conclusions.

TalkTalk suffered a major outage caused by rodent damage to fibre optic cables in 2017.

Sealing Cables & Ducts

Rat & Rodent Testing

Filoform have carried out tests to assess the physical damage caused to the FiloSeal+HD cable sealing sealant by a group of four rats (two males and two females) which are given free access to the duct seal for a period of four weeks.

The FiloSeal+HD comprises of MD+ sealant with hexagonal tubes as the backing product which was positioned within a metal tube.

Each end of the tube was sealed with 25mm of MD+ sealant ensuring that access to the backing product could only be achieved by significant damage to the MD+ sealant.

This tube was mounted in the center of the cage and consequently, the male and female sides of the cage had access to opposite ends of the tube.

Test cage before start of study

Immediately before rats placed in cage – side exposed to males	Immediately before rats placed in cage – side exposed to females
After one week of exposure – side exposed to males	After one week of exposure – side exposed to females
After four weeks of exposure – side exposed to males	After four weeks of exposure – side exposed to females

Duct Seals | Substations

Conclusion

The results at the end of the four week study indicated that there was no apparent difference in the damage caused by the male rats in comparison to the female rats and though the damage increased over the duration of the study the MD+ duct sealant was not penetrated by the rats and the hexagonal backing tubes were not exposed or damaged.

No abnormalities, ill health or behavioural changes occurred to the rats during the study and all four rats achieved satisfactory body weight gain during the exposure period.

Several hard red pieces were observed in the large intestines of one female and in the stomach of one male and one female. There were no other abnormalities observed at the post mortem macroscopic examination at study termination on Day 29.

In conclusion as the hexagonal tubes were not damaged after 4 weeks of exposure with direct access, therefore, it is reasonable to assume that different backing products will be protected to a similar degree, when enclosed by MD+ cable duct sealant.

THORNE & DERRICK are national distributors LV, MV & HV Cable Installation, Jointing, Substation & Electrical Equipment – we service UK and global businesses involved in cable installations, cable jointing, substation, overhead line and electrical construction at LV, 11kV, 33kV and EHV.

Since 1985, T&D have established an international reputation based on SERVICE | INTEGRITY | TRUST.

Contact us for 3M Electrical, ABB, Alroc, AN Wallis, CATU Electrical, Cembre, Centriforce, CMP, CSD, Elastimold, Ellis Patents, Emtelle, Euromold, Filoform , Furse, Lucy Electric & Zodion, Nexans, Pfisterer, Polypipe, Prysmian, Roxtec, Sicame, WT Henley.

Invitation

Thorne & Derrick invite you to join LinkedIn’s largest LV-HV Electrical Discussion Group : Low & High Voltage Power, Cabling, Jointing & Electricals. Discussion subjects include cable installations, cable jointing, substation, overhead line and electrical construction at LV, 11kV, 33kV and EHV. Network, engage and promote your profile, company or products with over 10,000 influencers.

Armoured Cable Joints | SWA Cables

Cable Joints for LV SWA Armoured Cables

➡ Thorne & Derrick stock and distribute a complete range of Armoured Cable Joints (SWA) in resin cast, cold shrink or heat shrink types for the connection and jointing of multicore and single core XLPE insulated power cables with armour and stranded copper conductors up to 600/1000V – joint kits are available for both AWA (aluminium armoured) and SWA (steel armoured) cables.

Complete supporting range of electrical compression connectors manufactured by Cembre are available and compatible with all types of armoured cable joints.

For further information please visit LV Cable Joints.