R&D Cable Jointing Ltd | LV–33kV Cable Jointing & Substation Services
Based in Kent — Working Nationwide
0330 043 6689 info@rdjointing.co.uk
HV / LV Cable Jointing & Substation Services

Nationwide Power
Solutions.

LV – 33kV Cable Jointing & Terminations / Substation Installation / Testing & Commissioning / SAP Services

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LV – 33kV
Full voltage range
30+
Years combined experience
UKwide
Nationwide reach
AIS Utilities
UK Power Networks
Total Utility Connections
Eclipse Power Networks
ESP Utilities Group
Fulcrum
SAS Utility Services
Energy Assets Networks
UK Power Distribution
ErithConnect
LYES Electrical
SWAT Utilities
M&M Contractors
TheICP
RB Utilities
AIS Utilities
UK Power Networks
Total Utility Connections
Eclipse Power Networks
ESP Utilities Group
Fulcrum
SAS Utility Services
Energy Assets Networks
UK Power Distribution
ErithConnect
LYES Electrical
SWAT Utilities
M&M Contractors
TheICP
RB Utilities
What We Do

Complete HV/LV jointing
& substation services

From 11kV cable jointing to full substation fit-out. We support utilities, ICPs, IDNOs, civil contractors and private networks with consistent, quality-assured delivery.

01

HV Cable Jointing

11kV and 33kV cable jointing, repairs and diversions. Straight joints, transitional joints and terminations into switchgear, transformers and RMUs.

Explore 02

HV Substation Services

Full substation installation and fit-out to DNO/IDNO specifications. Small power, lighting, earthing, CT wiring for metering and LV STC panel installation.

Explore 03

Testing & Commissioning

Prove the integrity of your installation before energisation. Sheath testing, VLF, secondary injection and DNO/IDNO compliance support through to handover.

Explore 04

SAP Services

Senior Authorised Person attendance up to 33kV. Switching, permits, isolation and live working supervision for planned and emergency works.

Explore 05

LV Cable Jointing

MSDB installation, service and cutout terminations, lateral cable installation and mains jointing to IDNO specification. All LV cable types.

Explore 06

HV Fault Response

Emergency and out-of-hours HV cable fault attendance. We mobilise quickly, work under outage constraints and support full fault-to-repair reinstatement.

Explore 07

HV Cable Terminations

Indoor and outdoor HV cable terminations for 11kV and 33kV circuits. Cold shrink, heat shrink and push-on termination systems to manufacturer procedures.

Explore —

View All Services

EV / Solar / BESS substations, joint bays, cable routes and substation earthing works.

All services
R&D Cable Jointing — LV to 33kV
R&D Cable Jointing Ltd — LV to 33kV, South East & Nationwide
Scope of Work

One Contractor.
Full Scope.

  • LV – 33kV Jointing (PILC, XLPE, Waveform — all cable types)
  • Full Substation Installation & Fit Out to DNO / IDNO specification
  • Small Power & Lighting Install — internal and external substation
  • Internal & External Substation Earthing
  • CTs & CT Wiring for COP3/5 Metering Box Installation
  • LV STC Panel Installation & Commissioning
  • DNO/IDNO Compliance, Audit Support & Connection Day Management
  • MSDB Installation, Lateral Cable & Cutout Terminations
  • EV / Solar / BESS Substations — HV/LV works, all types
  • Off-site Civils — Joint bays, cable routes, dig, backfill, reinstate & substation bases
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Why R&D

A contractor that delivers
without the drama

As a family-run business, our reputation is everything. You deal directly with the people doing the work — no layers, no hand-offs, no surprises.

Proven Expertise

30+ years of combined experience across HV cable jointing, substation works and SAP services. We've seen almost every cable type, joint type and site constraint — and we know how to deliver cleanly within them.

End-to-End Capability

From cable installation and jointing through to testing, commissioning and DNO adoption attendance — we can handle every stage. One contractor, clear accountability, no gaps in the handover chain.

Fully Insured & Compliant

Public and employer's liability cover in place. We work to manufacturer procedures, DNO safety rules and site-specific RAMS — and we bring the paperwork ready, not as an afterthought.

A Personal Approach

You'll deal with David and Ricki — the founders — not an account manager. We respond quickly, communicate honestly, and take pride in the work. If there's a problem on site, we tell you before you find out elsewhere.

Trusted By

Some of the contractors and networks
that trust us

AIS Utilities
UK Power Distribution
Energy Assets Networks
Fulcrum
Eclipse Power Networks
ESP Utilities Group
SAS Utility Services
ErithConnect
LYES Electrical
M&M Contractors
Total Utility Connections
TheICP
RB Utilities
Last Mile
MUA
How We Work

From scope to sign-off

A clear, repeatable process that fits around your programme — not ours.

1

Scope Review

Drawings, cable types, joint types, access, outage windows and programme constraints reviewed upfront.

2

RAMS & Programme

Method statements aligned to your site rules, permits and operational requirements — ready before mobilisation.

3

Controlled Installation

Clean workmanship to manufacturer procedures. No shortcuts, no rework, no surprises for the test team.

4

Inspection & Handover

Clear records, photographs where required and sign-off support ready for your QA or client audit.

5

Testing & Close-Out

Support through testing, energisation and defect close-out. We stay engaged until the job is properly done.

Technical Insight

Written by jointers.
Not a marketing team.

Practical technical guides on HV cable jointing, testing methods and fault location — written from experience on real networks.

11kV

11kV Jointing Methods

Cold shrink, heat shrink and push-on joint systems for XLPE and PILC — selection, procedure and quality checks.

 33kV

33kV Termination Procedure

Step-by-step guidance on 33kV cable termination including stress control, screen termination and testing.

 Testing

HV Cable Testing: VLF vs DC

Why VLF has replaced DC hipot testing for XLPE cables — the engineering case explained clearly.

 Fault Location

Cable Fault Location Methods

TDR, decay method, surge pre-location and acoustic pinpointing — how the techniques work and when to use each.

 Industry

ICPs, DNOs & IDNOs

Understanding who does what on a new development connection — and where specialist jointing contractors fit.

 Industry

Contestable vs Non-Contestable

What you can competitively tender and what only the DNO can do — essential for developers and project managers.

 Renewables

Solar, BESS & Wind HV Jointing

The specific HV jointing and fault finding requirements of solar farms, battery storage and onshore wind sites.

 EV Charging

Commercial EV Charging Infrastructure

LV feeder pillars, 11kV substations and HV cable jointing for commercial EV charging — car parks, fleet depots, housing and hospitality.

FAQs

Your questions answered

With decades of combined experience, R&D Cable Jointing is trusted across the UK. Got a question not listed? Get in touch.

What areas do you cover?
Based in the South East (Kent), we work nationwide. We regularly support projects across Essex, London, Kent, Hertfordshire, Surrey, Suffolk, Cambridgeshire and Bedfordshire — and we travel further for the right project. Just get in touch with your location.
What voltages can you work with?
LV, 11kV and 33kV. Our SAP authorisations cover up to 33kV for switching, permits and live working supervision.
What types of cable do you joint?
PILC, XLPE, Waveform and other common LV/HV cable types. If you're unsure whether we can handle your cable type, just ask — we've likely worked with it before.
Can you handle a full substation installation?
Absolutely. We handle everything from landing, earthing and fit-out through to testing, commissioning, DNO audit attendance and taking control of the LV network on connection day on behalf of the IDNO.
What's the difference between a jointer and an SAP?
A jointer physically installs and connects cables. A Senior Authorised Person (SAP) is responsible for issuing permits and ensuring the system is safe to work on. We provide both in-house — which means you don't need to co-ordinate separate contractors for jointing and SAP attendance.
Can you supply materials or do you work labour-only?
Both. We're happy to supply jointing kits, accessories and materials, or to work with your own supplied materials — whatever suits the job and your procurement arrangements.
Do you have emergency / out-of-hours availability?
Yes — emergency and out-of-hours response is available by agreement. For cable fault repair situations, contact us directly on 0330 043 6689 and we will advise on availability and attendance time.
How do I get a quote?
Send the scope and location to info@rdjointing.co.uk or use the Request a Quote form. We'll come back to you quickly with availability and a straightforward plan — no lengthy tender process for routine jointing works.

Ready to discuss your project?

Send us the scope, cable type, voltage and location and we'll come back with availability and a clear plan. No lengthy process — just a straight answer.

Request a Quote Or call us: 0330 043 6689

Also need cable fault location?

CableFaultLocation.co.uk
Qualified & Certified

Industry recognised credentials

EUSR Qualified

EUSR Registered

Citrus Training

Trained at Citrus Training

Fully Insured

UKPN
Standards

Trained to UKPN Standards

HV/LV jointing or substation project coming up?

If you have a project or need advice, we're happy to talk through the scope before you commit to anything. Get a quote or call us today.

Request a Quote 0330 043 6689