Older consumer units
Boards that are 20, 30 or 40 years old often lack modern protection, have no spare ways and use old-style fuses rather than breakers.
Fuse box upgrades for EV charging · Derby
Fuse box and electrical upgrades for EV charging in Derby
Consumer unit upgrades, RCD/RCBO and surge protection, earthing and load checks, so your home or business can run an EV charger safely, reliably and to current regulations.
Quote within 24 business hours: send photos or a short video of the job, with your name, on WhatsApp, or request a quote online.
- Serving Derby since 2009
- NAPIT registered
- Certified to BS 7671
- Homes and businesses
Can your electrics support an EV charger?
Before installing a charger, the first question is whether your property has the capacity to support it safely. Chargers draw a lot of power for hours at a time, and while most modern properties can accommodate one, many older consumer units or heavily used systems need some upgrades first.
A dedicated EV circuit has to run safely alongside everything else. Without enough spare capacity or the right protection, a charger can cause nuisance tripping, overheating or more serious risks.
That's why every installation starts with an assessment of your consumer unit, main fuse, earthing and overall demand. Most Derbyshire properties are suitable for smart EV charging once the right checks and protection are in place, and if anything needs upgrading we explain it clearly.
Why fuse box upgrades are often needed
No RCD or RCBO
An EV charger must be on a circuit with RCD or RCBO protection. If your board doesn't have it, it needs adding or upgrading.
No surge protection
Current wiring regulations call for surge protection on many installations, including EV chargers. Older boards rarely have it.
Limited spare capacity
If there's no free way, or the main fuse is already close to its limit, extra work is needed to avoid overloading the system.
Extensions and alterations
Added kitchens, bathrooms and loft conversions often fill the original board, leaving no space for a dedicated EV circuit.
Long-term safety
An upgrade makes the whole installation safer and ready for future appliances, extensions and renovations, not just the charger.
Electrical safety requirements for EV chargers
Regulations for EV circuits are stricter than for most household circuits. Several protections must be in place before a charger can be connected.
- RCD or RCBO protection: preferably an RCBO, which combines residual current and overcurrent protection on the EV circuit
- Surge protection (SPD): protects the charger, your car and your appliances from voltage spikes
- Correct earthing: we check PME (TN-C-S) supplies and whether extra protection or an earth rod is needed
- Main bonding: adequate bonding to gas and water pipes, upgraded if missing or undersized
- A dedicated circuit: the charger can't share a circuit with sockets or appliances
All work is carried out to current BS 7671 wiring regulations. A new EV circuit is notifiable under Part P of the Building Regulations, which we handle through our NAPIT registration.
Load calculations and capacity checks
Before installing a charger, we calculate your property's demand, including heating and hot water, cooking, showers and immersion heaters, lighting, sockets and, for workplaces, machinery and IT, and compare it with the capacity of your supply.
Most Derbyshire homes have a 60A, 80A or 100A main fuse, and EV chargers typically draw 16A to 32A. If the main fuse is already close to its limit, or several high-demand appliances run at once, charging needs managing.
- Load balancing to reduce charging power when demand is high
- Smart systems that distribute power safely
- Advice on changing when you use high-demand appliances
- Liaising with your DNO if a supply or main fuse upgrade is needed
Hot tubs, electric showers, underfloor heating and multiple EVs need extra planning. For businesses, we calculate peak loads so multiple workplace chargers don't disrupt essential operations.
Fuse box and electrical upgrade costs
Upgrades aren't always needed, but when they are, these are typical costs:
| Upgrade | Typical price |
|---|---|
| RCD/RCBO protection, where the board has space but lacks the right protection | £40–£120 per device |
| Surge protection device (SPD) | £70–£150 |
| Partial consumer unit upgrade: extra ways, new breakers or upgraded protection | £150–£350 |
| Full consumer unit replacement for old fuse boxes, no RCD protection, limited capacity or signs of overheating | £450–£750 |
| Earthing and bonding upgrades to gas and water supplies, or additional earthing | £80–£250 |
| Load management module for dynamic load balancing | £50–£150 |
We confirm exactly what's needed, and the price, after looking at photos or surveying your board. See our EV charger installation costs for full installation prices, or our consumer unit upgrades page for upgrades without a charger.
Types of upgrade we provide
New consumer units
Individual RCBO protection, built-in surge protection and spare capacity for future circuits, meeting current regulations.
Dedicated EV circuits
Correct cable size, protective devices and routing, so the charger gets a stable, safe supply.
RCD and RCBO upgrades
Some newer boards only need extra protection for the EV circuit, which can be a cost-effective way to meet charger safety requirements.
Earthing and bonding
Undersized or missing bonding upgraded, and the earthing arrangement made safe for EV charging, including PME supplies.
Distribution boards for businesses
New breakers, extra ways, upgraded boards or extended circuits for workplace charging, with minimal disruption.
Remedial work
Tidying previous wiring, replacing outdated components and correcting DIY alterations before the charger goes in.
Preparing older homes and extensions
Derbyshire has everything from Victorian terraces and 1930s semis to new builds and extended homes. Homes built before the 1990s often have ageing consumer units, no RCD protection and limited capacity, and wiring that has been extended over the years, so we assess its condition carefully.
Where the charger needs to go on a detached garage, outbuilding or garden room, cable runs are longer and may need burying, conduit or protective ducting, all weather-resistant and compliant.
Mixed wiring standards and DIY alterations aren't unusual in older homes. If we find anything that could compromise safety or performance, we explain the options and put it right. From terraces near the city centre to post-war semis in Mickleover, Allestree and Littleover, we tailor the work to the property.
What happens during an upgrade
- Isolate and remove We agree a time, isolate the supply and remove the old board or prepare for added protection, tidying the wiring behind it.
- Fit and label The new consumer unit or protective devices go in, with RCBOs and SPD where needed and every circuit clearly labelled.
- Test and certify Loop impedance, RCD/RCBO trip, bonding and continuity tests, then an Electrical Installation Certificate or Minor Works Certificate.
- Install the charger The property is left tidy and ready for the charger installation, the same day or when it suits you.
Why electrical safety matters for EV charging
Installed correctly, EV charging is very safe. Rushed installations without the right upgrades can overload circuits, causing nuisance tripping or overheating, and without RCD, RCBO and surge protection a fault could create a shock risk or damage the charger and your car's electronics.
Old fuse boxes, undersized wiring and DIY work increase fire risk under the sustained load of EV charging, and a charger on an inadequate supply may run slowly or fail to hold full charging power. Upgrades aren't about selling extra work; they make sure your property can handle the technology safely and reliably.
Fuse box upgrade FAQs
Do all homes need a fuse box upgrade before installing a charger?
No. Many modern consumer units already meet the requirements. An upgrade is only needed if your board lacks capacity or the correct protection.
What's the difference between an RCD and an RCBO?
An RCD protects a group of circuits against earth leakage. An RCBO combines that protection with overcurrent protection for a single circuit, which is the safer and more reliable option for an EV charger.
How do I know if my earthing is suitable for EV charging?
We test your earthing during the survey, including PME supplies. If it isn't suitable, we recommend safe, compliant upgrades such as additional protection or an earth rod.
How long does a consumer unit upgrade take?
Most upgrades are completed within a few hours, with the power off for part of that time. We agree a time with you in advance.
Can you tell if I need an upgrade from photos?
Often, yes. Photos of your consumer unit and main fuse usually show whether there's space and the right protection, and we confirm at the survey.
Will I get a certificate?
Yes. You receive an Electrical Installation Certificate or Minor Works Certificate depending on the work, and notifiable work is registered through NAPIT.
EV electrical upgrades across Derbyshire
We carry out upgrades for EV charging across Derby, including Mickleover, Littleover, Chaddesden, Oakwood and Spondon, and the wider county, including:
- Allestree
- Alfreton
- Ashbourne
- Belper
- Heanor
- Ilkeston
- Long Eaton
- Melbourne
- Ripley
- Swadlincote
- West Hallam
- South Normanton
Book an electrical assessment for EV charging
Send us a photo of your consumer unit and main fuse and tell us where you'd like the charger, and we'll tell you whether an upgrade is needed and what it will cost.
