GRP (Glass Reinforced Plastic) enclosures are widely used across industrial, infrastructure and outdoor electrical installations due to their corrosion resistance, durability and suitability for harsh operating environments. While the enclosure itself provides physical and environmental protection, the overall performance of the system depends heavily on the electrical equipment installed inside and how it is integrated.
Understanding what electrical equipment is typically housed within a GRP enclosure, and how systems can be supplied with equipment pre-installed, is important for designers, contractors and end users involved in modern electrical projects.
Electrical enclosures perform several critical functions within an installation:
GRP enclosures are particularly well suited to outdoor, coastal and chemically aggressive environments where metallic enclosures may suffer from corrosion, coating breakdown or long-term degradation.
The enclosure alone does not define system performance. Internal electrical equipment selection, layout and installation quality all influence electrical safety, thermal performance, ease of maintenance, reliability over the service life and commissioning efficiency.
For this reason, electrical equipment installed within a GRP enclosure should be considered as part of a complete, integrated system, rather than as individual components added later on site.
The internal configuration of a GRP enclosure depends on the application, but several categories of electrical equipment are commonly installed across industrial and infrastructure projects.
Many GRP enclosures are used as local power distribution points. Typical power distribution components include incoming isolators, single-phase or three-phase distribution boards, circuit breakers (MCBs), RCDs, RCBOs and fuse holders.
These components provide controlled power distribution and electrical protection for downstream equipment.
GRP enclosures are frequently used to house control and automation systems, particularly where installations are exposed to weather or corrosive atmospheres.
Typical control equipment includes PLCs, remote I/O modules, control relays, contactors, interface relays and terminal blocks. These systems are commonly used in applications such as pumping stations, water treatment works, traffic management systems and EV charging infrastructure.
Where motors or driven equipment are involved, GRP enclosures may house motor starters, contactors, overload relays, variable speed drives (VSDs) and soft starters.
In these applications, enclosure design must also consider ventilation, heat dissipation and internal spacing to support safe and reliable operation.
Modern electrical installations often include monitoring and communications hardware. GRP enclosures can accommodate energy meters, current transformers, voltage monitoring devices, data loggers, telemetry units and communication gateways.
The stable internal environment provided by a GRP enclosure helps protect sensitive electronic equipment in outdoor or industrial locations.
In addition to primary electrical equipment, GRP enclosures typically include supporting components such as mounting plates, DIN rail systems, cable management, earth bars, bonding arrangements and cable entry systems.
Correct internal layout supports accessibility, segregation, thermal performance and future maintenance.
Electrical equipment generates heat, and GRP enclosures are often installed in environments subject to temperature variation. Effective thermal management is therefore a key design consideration.
Typical provisions include internal LED lighting, anti-condensation heaters, thermostats and natural or forced ventilation. These measures help protect internal equipment, reduce condensation and support long-term reliability.
For many applications, we provide GRP enclosures with a standard internal electrical fit-out already installed. This approach is commonly used to reduce on-site work and simplify commissioning.
A typical pre-installed configuration may include:
All internal electrical assemblies are dead tested prior to delivery to verify wiring integrity and installation quality. This helps ensure the enclosure arrives on site prepared for connection and commissioning.
Where applicable, this standard pre-installed electrical option can be selected directly when ordering through our online store, allowing enclosures to be supplied ready for installation without additional site work.
While standard configurations are suitable for many installations, project requirements often vary. Where non-standard equipment is required, we provide the option to integrate alternative or additional electrical components into the enclosure during manufacture.
Examples may include additional socket outlets, control panels, communication equipment, monitoring devices or application-specific electrical hardware.
By supplying GRP enclosures with non-standard electrical equipment already installed, systems can be delivered fully assembled. In many cases, this reduces overall project cost by minimising on-site labour, shortening installation time and simplifying coordination between trades.
We provide a range of standard GRP enclosure sizes that can be adapted to suit internal equipment layouts, available via our online range.
Where applications require custom dimensions, layouts or fully integrated electrical systems, we also provide bespoke GRP enclosures designed and manufactured to suit project-specific requirements.
GRP enclosures with internal electrical equipment we provide are commonly used across EV charging infrastructure, water and wastewater treatment facilities, pumping stations, traffic and highways systems, renewable energy installations and industrial process control.
GRP enclosures provide a robust and corrosion-resistant housing for a wide range of electrical and control equipment. However, the enclosure alone does not define system performance. Internal equipment selection, layout and integration are critical to achieving safe, reliable and maintainable installations.
By providing GRP enclosures with pre-installed electrical equipment, we help simplify installation, improve quality control and support efficient project delivery. Standard configurations can be selected directly through our store, while bespoke electrical assemblies allow systems to be tailored to specific site requirements.
For further information or to discuss project requirements, please contact us.
