Industrial Electrical

11 kV Quarry Site Electrical Power Upgrade in Cornwall

Design, project management and delivery of a full quarry site power upgrade in Cornwall, centred on a 1500 kVA, 11 kV transformer with premium Schneider HV and LV equipment, containment, dedicated HV and LV earthing systems, groundworks and associated building work.

Cornwall

Maenporth Electrical Ltd designed, project-managed and delivered a full site power upgrade for a quarry customer in Cornwall. Developed around the customer’s stated power requirements, the project brought the high-voltage and low-voltage electrical infrastructure together with the groundworks and building activities needed to support the installation.

At the centre of the upgrade was a Bowers 1500 kVA, 11 kV to 415 V transformer. The wider electrical scope included premium Schneider HV and LV equipment, the LV installation, electrical containment, dedicated HV and LV earthing systems, and the connections serving the individual outgoing submains.

Three workers in orange high-visibility clothing stand beside two utility buildings on a muddy industrial site with puddles and aggregate piles.

Elevated view over a quarry site with a small white building, aggregate piles, haul vehicles and temporary fencing.

Maenporth Electrical Ltd managed the project from the assessment of the quarry’s power requirements and preparation of drawings through to the electrical and construction work. This coordinated approach kept the transformer, switchgear, LV infrastructure, containment, earthing, groundworks and supporting building work within one defined project scope.

Quarry power requirements and project design

The project began with an assessment of the quarry site’s power requirements. This provided the basis for developing the planned infrastructure around the customer’s stated needs rather than treating the transformer as an isolated equipment installation.

Project drawings were produced to define the proposed work and support its management on site. They provided a common reference for the transformer installation, HV and LV equipment, containment routes, earthing arrangements and associated structures. The drawings also helped to maintain the relationship between the electrical installation and the physical work required around it.

Open electrical cabinet containing five large coloured cables connected to copper bars, with a digital hand tool resting below.

On an industrial site of this type, the principal electrical equipment cannot be considered separately from its surroundings. The transformer position and support, routes for electrical services, containment, underground infrastructure and earthing arrangements all had to form part of the same overall design. The associated construction activities were therefore included in the project rather than being treated as unrelated works.

Managing the complete electrical and construction scope

In addition to carrying out the electrical installation, Maenporth Electrical Ltd project-managed the wider quarry power upgrade. The scope extended from the initial assessment and drawings to the transformer, HV equipment, LV distribution, containment and dedicated earthing systems, together with the practical building and groundworks required for the new infrastructure.

Bringing these activities into one managed project allowed the electrical equipment and its physical setting to be developed in line with the drawings and the customer’s stated requirements. It also meant that the ground and building works could be coordinated with the position of the equipment, service routes, containment and earthing arrangements.

The principal elements of the project were:

Assessment of the quarry site’s stated power requirements
Preparation of project drawings
Installation of a Bowers 1500 kVA, 11 kV to 415 V transformer
Premium Schneider HV and LV equipment
A Schneider ring main unit providing electronic trip protection
Schneider MicroLogic 7 protection for the individual outgoing submains
LV electrical installation and associated connections
Electrical containment
Dedicated high-voltage and low-voltage earthing systems
Groundworks and supporting construction activities
Blockwork, timber work and a sheet-metal roof

This combined scope reflects the practical demands of industrial electrical work on a quarry site. Delivering the power upgrade involved not only installing the principal equipment, but also providing the electrical and construction infrastructure required to support, house and connect it.

1500 kVA, 11 kV transformer installation

A central part of the upgrade was the installation of the Bowers 1500 kVA transformer, operating from 11 kV to 415 V. The transformer formed part of the wider site power installation designed around the quarry customer’s stated requirements.

This was not treated as a standalone equipment replacement. The transformer installation sat within a broader package covering project design, HV equipment, LV infrastructure, electrical containment, dedicated earthing systems and the construction work associated with the new installation. Each element was managed as part of the full quarry site upgrade.

Mobile crane lifting a large grey transformer beside scaffolding and industrial processing structures, with vans and concrete barriers in the foreground.

Worker in a hard hat and high-visibility vest standing beside a large black electrical transformer inside an unfinished blockwork room.

Open trench containing several red ducts, yellow warning tape and a timber board, surrounded by excavated sandy ground.

Including the transformer and its supporting work within the same project maintained a clear relationship between the 11 kV equipment, the 415 V installation and the infrastructure needed to support and connect them. The transformer’s installation could therefore follow the same drawings and design basis as the wider electrical system and associated building work.

Schneider RMU and electronic trip protection

Premium HV equipment was used for the project, including a Schneider ring main unit. The RMU was installed to provide electronic trip protection for the Bowers 11 kV to 415 V, 1500 kVA transformer.

This HV equipment formed part of the coordinated installation rather than a separate package. Its position and function were considered alongside the transformer, dedicated HV earthing system, LV distribution arrangements and supporting construction work.

LV installation and outgoing submain protection

Alongside the 11 kV transformer and HV equipment, Maenporth Electrical Ltd carried out the LV installation. This formed an essential part of the wider site power infrastructure, extending the project beyond the transformer itself and into the distribution arrangements required for the quarry site.

Premium Schneider LV equipment was selected for this part of the work. Schneider MicroLogic 7 was installed to provide the latest protection on each individual outgoing submain. This protection equipment was incorporated into the LV scope and coordinated with the transformer and the wider site installation.

Large grey electrical switchgear cabinet with multiple compartment doors, black operating handles, an exposed upper busbar section and heavy cables entering from above.

The LV work also included the heavy connections associated with the distribution equipment. All connections were set to the manufacturers’ specified torque-setting requirements for warranty purposes. This ensured that the connections were completed in accordance with the equipment requirements rather than relying on an unspecified tightening method.

All crimped connections supplied as part of the project carry a lifetime guarantee. Together with the specified torque settings, this formed an important part of the approach to the project’s cable connections and terminations.

Electrical containment and service routes

The works included the containment required to support and route the site’s electrical infrastructure. This provided a practical link between the routes defined in the project drawings and the physical installation within the associated building areas and across the wider site.

Containment was included within the same coordinated electrical scope as the transformer, switchgear and LV installation. Its routing had to correspond with the equipment positions, outgoing submains, building layout and other supporting infrastructure included in the project.

Worker in orange high-visibility trousers fitting perforated metal cable tray to an overhead support system inside an industrial building.

Black perforated cable trays and silver metal containment suspended from the ceiling beside unfinished block walls.

By covering the LV installation and its containment as well as the principal HV equipment, the project addressed the broader infrastructure around the transformer. This was a complete site power upgrade rather than an installation focused only on the largest single item of equipment.

Dedicated HV and LV earthing systems

The quarry power upgrade incorporated dedicated earthing systems for both the high-voltage and low-voltage parts of the installation. The HV and LV earthing requirements were addressed through separate systems within the overall project design and installation.

Earthing was treated as a defined element of the upgrade rather than an incidental addition to the transformer or LV work. Including it within the drawings, project management and installation scope allowed the separate HV and LV arrangements to be considered alongside the relevant equipment, containment, cable routes and groundworks.

Grid of bare copper-coloured conductors laid across the base of a large excavation, with a worker, excavators and a white van nearby.

Worker in orange protective clothing and a white hard hat standing among marked lines on prepared ground, with a tracked excavator and industrial tanks behind.

This part of the project demonstrates the breadth of the site infrastructure involved. The work covered the main transformer, Schneider HV and LV equipment, outgoing submain protection and containment while also extending into the ground-based infrastructure required to serve the two voltage levels.

Groundworks and supporting construction

The full project extended beyond the installation of electrical equipment. It included the groundworks and building activities required to create the physical setting for the new power infrastructure. Managing this work alongside the electrical scope helped to keep the supporting structures and service routes aligned with the project drawings.

The associated construction work comprised:

Close view of steel reinforcement mesh over yellow sheeting, with timber service formwork and a black pipe opening.

Concrete pump boom positioned beside a mixer lorry, with a worker in orange high-visibility clothing near a freshly poured slab.

Rectangular excavation containing steel reinforcement mesh and a curved grey conduit, with stacked paving blocks and traffic cones alongside.

Gravel-covered construction area between industrial buildings and silos, with shallow trenches, concrete blocks and a small compactor.

Worker in yellow high-visibility clothing kneeling beside a block edge around a reinforced foundation slab with timber formwork.

Two orange tracked excavators stand in rocky ground, one fitted with a hydraulic breaker and the other with a digging bucket.

Groundworks for the project infrastructure
Blockwork forming part of the supporting construction
Timber work within the building scope
A sheet-metal roof

The groundworks provided part of the practical foundation for the wider installation and its underground routes. The blockwork, timber work and sheet-metal roof formed the associated building scope around the electrical infrastructure. Together, these elements provided the physical support and enclosure required for the equipment included in the project.

The sequence and coordination of the construction activities were particularly relevant. Foundation and building work had to correspond with the planned equipment positions, containment, cable routes and earthing arrangements. Treating the construction and electrical elements as one managed scope retained that relationship as the project moved from drawings and ground preparation to equipment installation and electrical connections.

A coordinated industrial site power upgrade

This Cornwall quarry project combined electrical design, project management, HV and LV installation, containment, earthing, groundworks and construction. Maenporth Electrical Ltd’s involvement began with assessing the customer’s stated site power requirements and preparing project drawings, before progressing into delivery of the transformer and the infrastructure around it.

The technical scope centred on the Bowers 1500 kVA, 11 kV to 415 V transformer. A Schneider RMU provided electronic trip protection on the transformer, while Schneider MicroLogic 7 equipment provided protection for the individual outgoing LV submains. Dedicated HV and LV earthing systems addressed the separate earthing requirements, with containment and connections forming part of the wider distribution installation.

The connection work was completed to the manufacturers’ specified torque settings to meet warranty requirements, and all crimped connections carry a lifetime guarantee. These details were incorporated alongside the larger project elements rather than being separated from the overall installation.

At the same time, the project included the groundworks, blockwork, timber work and sheet-metal roof required to support and enclose the infrastructure. Bringing these disciplines together allowed the quarry power upgrade to be managed as one industrial site project developed around the customer’s stated requirements.

Industrial electrical work for quarries and larger sites

The project reflects Maenporth Electrical Ltd’s practical, technically capable and site-focused approach to industrial electrical work in Cornwall. It required high-voltage and low-voltage equipment to be coordinated with distribution, containment, separate earthing systems and the associated construction work for a substantial quarry site power upgrade.

Maenporth Electrical Ltd provides industrial and commercial electrical services, solar and renewables, electrical testing, planned maintenance and EV charging, as well as domestic electrical work. Based in Maenporth, the company works across Cornwall, including Falmouth, Penryn, Newquay, Carnon Downs and surrounding areas.

Quarry operators, factories, holiday parks and campsites, golf and leisure sites, commercial premises and larger rural sites can contact Maenporth Electrical Ltd to discuss planned electrical infrastructure work. Call 01326 250297.

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