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Lock Out Tag Out for Electrical Safety: Secure Isolation with Marechal Solutions

February 27th, 2026

How to Lock Out and Tag Out a Marechal Socket Outlet

Electrical safety is a critical priority in industrial environments. When servicing or maintaining equipment connected to a power source, proper Lock Out Tag Out (LOTO) procedures are essential to prevent accidental energisation.

This guide explains how to safely lock out and tag out a Marechal socket outlet, ensuring compliance with site safety requirements while protecting personnel from electrical hazards.

Why Lock Out and Tag Out a Marechal Socket Outlet?

Marechal socket outlets are engineered for safety and reliability, however all electrical systems must be correctly isolated before maintenance or servicing begins.

Lock Out Tag Out helps to:

Prevent unintended reconnection of power
Protect personnel from electric shock or arc flash
Clearly communicate isolation status
Support workplace safety compliance
Maintain safe control of electrical energy

When Is Lock Out Tag Out Required?

A Marechal plug socket outlet should be locked out whenever:

Maintenance, inspection or repair work is taking place
Connected equipment is being serviced or modified
There is risk of unexpected energisation
The outlet or plug is damaged
Temporary electrical isolation is required

Equipment Required

Required Safety Equipment

Marechal-compatible socket outlet lockout device
Personal safety padlock
Lock out warning tag
Appropriate PPE

Step-by-Step: Locking Out a Marechal Socket Outlet

1. Identify the Correct Socket Outlet

Confirm the socket outlet supplying power to the equipment and verify the correct isolation point before proceeding.

2. Notify Affected Personnel

Inform nearby workers and responsible personnel that isolation will take place to prevent accidental reconnection.

3. Disconnect the Plug

Safely unplug the Marechal connector and ensure all connected equipment has stopped operating.

4. Apply the Lockout Device

Install the lockout device over the socket outlet to physically prevent reinsertion of a plug.

5. Secure with a Safety Padlock

Attach your personal safety padlock. Only the person carrying out the work should retain the key.

6. Attach the Lock Out Tag

The lock out tag should clearly display:

Warning message such as “Do Not Operate”
Name of responsible person
Date of isolation
Reason for lockout

This provides clear visual communication across the worksite.

7. Verify Isolation

Confirm the outlet cannot be energised by testing that a plug cannot be inserted or power restored.

8. Carry Out Maintenance Work

Once isolation is verified, maintenance or servicing can safely proceed.

9. Removal of Lock Out and Tag

Ensure tools and personnel are clear
Confirm the area is safe
Remove lock and tag personally
Notify personnel before re-energising

Marechal Electric Safety Solutions

Marechal socket outlets and decontactors provide safe electrical isolation for industrial power applications including generators, motors, distribution systems and hazardous area installations.

Correct Lock Out Tag Out procedures ensure safe maintenance practices while maintaining compliance with industrial electrical safety standards.

Choosing the Right Cable Cleat: A Practical Guide (IEC 61914 + Installation Tips)

February 23rd, 2026

Selecting the Right Cable Cleat: A Complete Guide

Fault restraint • IEC 61914 • Practical installation

Selecting the right cable cleat is a key part of designing and installing a reliable power distribution system. In environments such as industrial facilities, critical power and other electrical installations, cable cleats help ensure a short-circuit event does not escalate into major cable or equipment damage.

During a fault, electromagnetic forces rise rapidly and can cause cables to move violently. Correctly selected and installed cleats restrain cables during these brief but critical moments — supporting safety, equipment protection and overall system integrity.

This guide sets out practical steps to support cable cleat selection: understanding fault forces, the variables that influence cleat performance, and how to choose solutions that suit your cable formation, tray/ladder geometry and site constraints.

Fault Current Potential & Why It Drives Cleat Selection

Short-circuit events generate strong electromechanical forces between conductors. Cable cleats must restrain cables so that containment is maintained and damage risk is reduced. IEC 61914 provides methods and test requirements that help engineers assess performance against short-circuit forces. Forces are affected by peak fault current, cable spacing, cable formation (e.g., trefoil versus flat), conductor/cable diameter and cleat spacing.

Understanding these inputs helps narrow down suitable cleat types and installation approaches.

Peak short-circuit current influences the maximum electromagnetic forces.
Cable formation (trefoil/flat) changes how forces act between phases.
Cable diameter & spacing affect phase separation and load conditions.
Cleat spacing changes how much load each cleat must restrain.

LV vs MV/HV: What Changes for Cable Cleats

IEC 61914 defines LV cables as those rated up to 1.0 kV AC (or 1.5 kV DC). Above these levels, cables are treated as MV/HV for testing purposes. In practice, higher voltage systems can be associated with higher prospective fault levels, which increases the importance of verified cleat performance, correct cleat spacing and robust installation.

Key Factors That Drive Cable Cleat Selection

Cable cleat selection typically comes down to a handful of practical variables. Getting these right helps ensure compliance, performance and installability.

1) Short-circuit rating requirement

The cleat must be suitable for the prospective fault level, cable formation and cleat spacing used. Where fault levels are high, retention performance and mechanical robustness become critical.

2) Cable diameter & adjustability

Cleats must fit the actual cable OD and the selected formation. If diameters vary on-site, solutions with a wider usable diameter range can help reduce SKU complexity and simplify procurement.

3) Tray/ladder geometry

Rung/slot dimensions, access to fixings and allowable cleat spacing can dictate what works in practice. Always ensure the chosen cleat can be mounted correctly on the tray or ladder system used.

4) Installation workspace

Limited access (overhead, congested runs, risers) can make bolt tightening difficult. Consider how the cleat installs in real conditions: tooling, access underneath the rung, and whether installation must happen before or after cable pull.

5) Environment & compliance

Consider corrosion exposure, UV, temperature, and any project-specific requirements. Standards-based testing and appropriate materials (e.g., stainless steel and protective liners/coatings) are often important for longevity and cable protection.

Practical rule of thumb

Cable cleats aren’t just tidy cable management. They are a mechanical safety component designed to restrain cables during short-circuit conditions.
Start with prospective fault level and formation, then work outwards to spacing, mounting geometry and installation constraints.

When BAND-FAST Cable Cleats Are Typically Considered

In high-fault applications and congested tray systems, installation practicality can matter as much as the short-circuit rating. BAND-FAST cable cleats are often considered where a robust retention solution is needed and where post-pull installation offers a practical advantage. Typical drivers include:

High retention requirement within the rated test envelope
Constrained access (overhead tray, risers, tight corridors)
Post-pull installation preferred to avoid interfering with pulling equipment/rollers
Reducing SKU complexity where cable diameters vary across projects

Tray Slot Width: Quick Compatibility Check

Before specifying band-style cleats, check tray or ladder slot dimensions. If rung slots are below the required width, feeding/locating the band can be inconsistent and another cleat style may be more suitable. Example minimum slot width guidance (confirm against the specific BAND-IT cleat/tooling selected):

5/8″ coated band: slot width ≥ 17.5 mm
5/8″ uncoated band: slot width ≥ 17 mm
3/4″ uncoated band: slot width ≥ 20 mm

Summary: How to Choose the Right Cable Cleat

Use this selection flow to keep decisions consistent:

Define prospective fault level and verify the required short-circuit rating.
Confirm cable formation (trefoil or flat) and actual cable outside diameters.
Set cleat spacing aligned to test declarations and project constraints.
Validate mounting geometry for the tray/ladder system (slots, rungs, access).
Account for the environment (corrosion/UV/temperature) and any project standards.
Choose an installation approach that works on site (pre-pull vs post-pull, access, tooling).

Specify BAND-IT Cable Cleats with Confidence

Tell us your cable sizes, formation, tray/ladder type and prospective fault level. We’ll help you identify a compliant, practical cable cleat solution for your installation.

Selection Support • Standards-Led Guidance • Project-Ready Supply

Clicks Can’t Replace Competence: Why HV & ATEX Safety Demands Human Expertise

February 17th, 2026

Why HV & ATEX Demand Expert Partnerships

Compliance-first • Engineering-led • Project-ready

Beyond The Net: Why HV & ATEX Demand Expert Partnerships

In an era of click-based procurement and AI-driven recommendations, a critical question is amplifying across energy and process industries. When lives and multi-million-pound assets hang in the balance, are your buying processes safe and robust?

For Thorne & Derrick International, the answer today is “probably not”. Thorne & Derrick has deliberately and clearly positioned itself not as a catalogue supplier, but as a solutions-based consultative partner adding high value expertise to energy supply chains globally.

What Thorne & Derrick Deliver

The Thorne & Derrick team of highly trained Technical Sales Engineers provides correct product specification and supply supplemented by value-added services. This includes supporting customers with system design, site survey, field training, product demonstration and CPD-accredited courses. In hazardous areas and high-voltage industries, where a single mis-specified component can trigger catastrophic system failure, this distinction isn’t commercial nuance — it’s a safety imperative.

Technical support and consultative engineering expertise

The Risk in Digital-Only Procurement

The rise of online B2B marketplaces and impersonal web-based stores has transformed industrial purchasing, bringing speed and transparency to many categories but dumbing down decision-making and introducing error into customer carts. Beyond doubt in HV, ATEX, IECEx and DSEAR-regulated environments, digitisation carries some serious risks. Whilst products may appear dimensionally identical across three suppliers online, subtle yet critical differences in product specification can dangerously go unnoticed.

Never mind mis-selection — counterfeit is common; product faking is rife.

Quote

“Customers aren’t buying a commodity,” explains Chris Dodds, Sales & Marketing Manager at Thorne & Derrick International. “They’re investing in a service that assures delivered products will comply and ensure optimum performance with built-in safety and reliability. This requires deeper intelligence beyond the datasheet to include the operating context; understanding explosion protection concepts, T Class, Gas Group, bushing interfaces and complex high-voltage cable specifications and configurations. No dropdown menu captures that.”

Product Compliance & Installer Competence

The Thorne & Derrick philosophy underpins their business model: Sales Engineers undergo continuous professional development training in hazardous area and high voltage standards, product technology, selection, installation and application engineering. The investment upholds a core belief: Product Compliance & Installer Competence must exist alongside industry regulation and technology.

From 600V to 66kV, from Zone 1 to Zone 21, they are committed across the business to supporting the delivery of safe projects. The common thread isn’t product breadth alone; it’s the application of contextual intelligence to match equipment specification with site reality to deliver that safety.

Safety as a Shared Outcome

Thorne & Derrick support a sharpened commitment: Certified Products, Installed Competently. Certification validates the product’s design integrity and assurance emerges from the correct selection. Competency is assured by training and ongoing development to ensure the highest levels of installation workmanship. One without the other creates vulnerability.

The Human Layer in an Automated World

As the energy mix accelerates through renewables, decarbonisation, hydrogen, battery energy storage and innovation in hazardous area processes, the complexity of Certification and Compliance intensifies. Legacy knowledge alone no longer suffices. In this dynamic landscape, Thorne & Derrick International positions its Sales Engineers not as checkout order-takers, but as active participants in clients’ safety ecosystems.

Technology will continue reshaping procurement. But in environments where error tolerance is zero, the human layer of expertise remains irreplaceable. Thorne & Derrick International’s value proposition rests on a simple, sobering premise: the cheapest or fastest option isn’t always the safest. And safety, ultimately, isn’t purchased—it’s engineered through partnership.

For engineers specifying critical infrastructure, that expert partnership may be the most important component in the bill of materials.

Partner with Thorne & Derrick

In HV and hazardous area environments where error tolerance is zero, our Technical Sales Engineers help ensure correct selection, compliance and safe performance in the real world.

Certified product selection support • Application engineering guidance • Project-ready documentation

The Ultimate Guide to Stokbord Cable Covers: Heavy-Duty Protection for LV, MV & HV Networks

February 6th, 2026

The Complete Guide to Stokbord Sheets & Cable Covers

For utility contractors and civil engineers, the risk of “striking” buried infrastructure is a daily operational hazard. Whether it’s an 11kV distribution line or a 132kV transmission cable, the consequences of accidental damage are severe, ranging from costly power outages to life-threatening injuries.

Enter Stokbord, the industry-standard solution for heavy-duty underground cable protection.

While Stokbord is widely known as a versatile recycled plastic sheet, in the utilities sector, it serves a specific, critical purpose: providing a high-impact, shatter-proof barrier over MV (Medium Voltage) and HV (High Voltage) cables.

In this guide, we explore why Stokbord has largely replaced concrete and tile tapes, the specifications you need to know (including ENA TS 12-23) and how to choose the right protection for your project available here at Thorne & Derrick.

Stokbord Drum MV HV Cable Protection for Underground Utility Cables

What is Stokbord?

Stokbord is a heavy-duty protection board manufactured from 100% recycled polyethylene. It is chemically inert, rot-proof, and exceptionally tough.

In the context of power distribution, Stokbord is used as a mechanical barrier installed in the trench directly above underground cables. Its primary job is to withstand the impact of hand tools (like spades) and offer significant resistance to mechanical excavators, alerting the operator to the presence of a cable before damage occurs.

Key Characteristics:

High Impact Resistance: Unlike concrete, which can crack or shatter, Stokbord absorbs energy and does not splinter.
High Visibility: Typically supplied with a red background and a yellow “Caution Electric Cable Below” strip, offering an unmistakable visual warning.
Lightweight: A single person can easily handle Stokbord sheets, significantly reducing manual handling risks compared to heavy concrete tiles.
DNO Approved: It is the preferred protection material for most UK Distribution Network Operators (DNOs), including UKPN, ENW, and SSE.

Which Stokbord Product Do You Need?

At Thorne & Derrick, we stock the full range of Centriforce Stokbord solutions, catering to voltages from 11kV up to 400kV.

1. Stokbord Cable Covers (The Standard Tile)

This is the traditional format rigid sheets (typically 1 metre in length) that are laid over the cable and interlinked. They are ideal for protecting high-voltage connections where a robust physical barrier is required.

Best for: 33kV, 66kV, and 132kV installations.
Common Sizes:
- Stokbord 1000mm x 152mm – Often used for smaller duct widths or single cables.
- Stokbord 1000mm x 244mm – The industry standard for 33kV cable protection.
- Stokbord 1000mm x 300mm – Wider coverage for larger trenches.
Specifications: Our stock meets ENA TS 12-23 (Class 1 & 2) and National Grid TS 3.05.07 requirements.

2. Stokbord Drum (The Safety Revolution)

The Stokbord Drum is a game-changer for site safety. Instead of individual tiles, the protection is supplied as a continuous strip on a reel.

Safety Benefit: It can be unrolled directly into the trench from the surface. This removes the need for operatives to enter the trench, eliminating confined space risks.
Speed: Installation is up to 30x faster than laying individual concrete or plastic tiles.

Alternative: Tapetile

For lower voltage applications (typically 11kV or street lighting) where a heavy rigid board isn’t specified, Tapetile is the standard alternative. It is a flexible, recycled plastic roll that offers visual warning and moderate protection, bridging the gap between simple warning tape and heavy-duty Stokbord.

Technical Specifications & Approvals

When procuring cable protection, “compliance” is the keyword. Using non-compliant materials can lead to project rejection by the DNO.

ENA TS 12-23 Compliance

Most UK utilities require protection that adheres to Energy Network Association Technical Specification 12-23. Stokbord sheets undergo rigorous impact testing to ensure they can withstand strikes without penetrating the cable below.

Class 1: Heavy-duty impact resistance (often required for 132kV+)
Class 2: Standard impact resistance (common for 33kV)

Dimensions & Thickness

While dimensions vary by DNO specification, standard thickness usually ranges from 6mm to 12mm

Length: 1000mm (standard tile)
Connection: Tiles feature pre-drilled holes and are supplied with plastic jointing pegs to lock them together, preventing gaps from forming during backfilling

Installation Guide: Best Practices

Correct installation is just as important as the material itself. Always refer to your specific DNO’s engineering standards (e.g., UKPN ECS 02-0019), but the general procedure is as follows:

Bedding: The cable should be bedded in fine fill (sand) to prevent damage from stones.
Placement: Place the Stokbord cover centrally over the cable.
- Standard Depth: Typically, the cover is placed 75mm to 150mm above the cable crown. This gap is crucial it ensures that if an excavator bucket hits the board, the force isn’t immediately transferred to the cable.
Jointing: Butt the 1-metre tiles together and insert the plastic peg through the pre-drilled holes to secure the joint.
Backfill: Carefully backfill over the covers.
Warning Tape: For High Voltage installations, an additional Underground Warning Tape is often placed 200-300mm above the Stokbord for an early visual warning.

Why Choose Stokbord Over Concrete?

We frequently get asked if concrete tiles are “better” because they feel heavier. In modern utility construction, the answer is almost always no.

Feature	Stokbord® (Recycled Plastic)	Concrete Tiles
Impact Behavior	Deforms and absorbs shock; shatter-proof.	Brittle; shatters on impact, creating sharp debris.
Weight	Lightweight; prevents repetitive strain injury.	Heavy; high risk of manual handling injury.
Installation Speed	Fast (especially with Stokbord Drum).	Slow; requires heavy lifting and careful placement.
Rot/Chemicals	Inert; 100% rot-proof.	Can degrade over decades in acidic soils.

Protect Your Infrastructures

At Thorne & Derrick, we are leading distributors of Centriforce products, supplying projects across the UK and internationally. Whether you are working on a wind farm connection requiring 132kV Type A covers or a local 11kV diversion using Tapetile, we have the stock and technical expertise to support you.

Efficiency Without Die Changes: The Klauke EK30IDML and EKM60ID Revolution

February 5th, 2026

The Klauke EK30IDML and EKM60ID Revolution

In the demanding world of industrial electrical installation, the goal is always a perfect balance between speed and precision. Traditional crimping methods, while reliable, often introduce an issue: the management of crimping dies. For every cross-section change or conductor class adjustment, an engineer must pause, locate the correct die and perform a physical swap.

Innovative dieless technology, embodied in tools like the Klauke EK30IDML and EKM60ID, is fundamentally changing this workflow. By moving away from fixed-die systems, professionals are now achieving a “gas-tight” connection with more versatility and significantly less downtime.

Whether you are working in a cramped control panel or on a major industrial installation, these tools are designed to think with you.

For more information on the full range see the Klauke Battery Operated Crimping Tools, or browse our range of compatible cable lugs and connectors.

The Game Changer: Dieless Indent Crimping

The standout feature of both the Klauke EK30IDML and its larger sibling, the Klauke EKM60ID, is the dieless indent system.

How it works: Instead of selecting a specific hexagonal die for a specific lug, the tool uses a patented indent profile that automatically adjusts its depth and force based on the resistance of the connector.

No more lost dies: No more searching through a heavy kit bag for the right size.
Reduced Error: Eliminates the risk of using the wrong die for a specific lug size, a common cause of joint failure.
Versatility: Perfectly suited for compacted conductors and fine-stranded conductors (Classes 2, 5, and 6) according to DIN VDE 60228.

EK30IDML: The Panel Builder’s Best Friend

The Klauke EK30IDML is the lightweight champion of the range. Weighing in at just 1.95kg (including battery), it is designed for ergonomic, one-handed operation in tight spaces.

Crimping Range: 6mm² to 120mm² (Cu).
Crimping Force: 30kN.
Battery: 10.8V Li-Ion with a 40-minute charge time.
Head Design: Closed, flip-top style and rotatable 350° for maximum accessibility.

EKM60ID: Power & Intelligence for Industrial Scaling

When the job requires larger cross-sections, the Klauke EKM60ID steps up. It features a unique two-stage telescopic cylinder that ensures optimal force is applied regardless of the cable size.

Crimping Range: Up to 240mm² (Cu) and 240mm² (Al).
Crimping Force: Variable 30kN – 60kN.
Smart Technology: Includes Bluetooth connectivity for the Klauke i-press app, allowing you to export crimping reports and verify the quality of every single joint.
Safety First: Available in the VDE Orange range, providing 1000V insulation for working in the vicinity of live parts.

Why Professionals use Klauke tools

Working with high-voltage and high-current systems requires trust in your equipment. As a specialist distributor Thorne & Derrick provide not just the tools but the technical expertise to ensure your team is equipped correctly.

Key Benefits of the ML Series:

Automatic Retraction: The tool automatically retracts once the correct pressure is reached, ensuring a perfect crimp every time.
LED Lighting: Integrated work lights for dark switchgear cabinets.
Battery Compatibility: Choose between Bosch or Makita battery platforms to match your existing tool fleet.

Cable cutting and crimping tools manufactured by Klauke are renowned for high-quality, electrical connection tools for cable crimping, cutting and punching – special cable tooling solutions for applications in a range of different sectors.

Klauke tools are used by electrical contractors, cable jointers and linemen for underground cable and overhead conductor crimping and cutting on power, transmission and distribution networks including LV MV & HV systems, 11kV-33kV up to 132kV – this includes battery, hydraulic and ratchet type cable cutters.

Battery operated cable crimping tools are made from the highest quality materials, rust proof and surface finished with a reputation for providing a long service live, consistently delivering safe electrical cable crimping connections for low and high voltage applications, 6-400sqmm. See also: Cable Cutters – Battery Type.