What Is an SPD in a Consumer Unit?
What Does SPD Stand For?
SPD stands for Surge Protection Device. It is a safety component installed
inside a modern consumer unit to protect electrical systems from voltage spikes.
These voltage surges can be caused by lightning strikes, switching operations from the
electricity network, or large appliances turning on and off.
A qualified Electrician in London
will often recommend installing an SPD when upgrading a consumer unit.
Why Surge Protection Is Important
Modern homes contain sensitive electronic equipment such as:
- TVs and home entertainment systems
- Computers and laptops
- Smart home devices
- Boiler control systems
- EV chargers
A sudden voltage spike can damage these devices instantly. An SPD helps divert
excess voltage safely to earth before it causes harm.
How an SPD Works
Under normal conditions, an SPD does nothing. However, when it detects a voltage
surge above a safe threshold, it activates instantly.
It redirects the excess voltage safely to earth, reducing the risk of equipment damage
and insulation breakdown.
Professional London Electricians
install SPDs according to manufacturer guidance and BS 7671 requirements.
Are SPDs Required in the UK?
Under the 18th Edition of the UK Wiring Regulations (BS 7671), surge protection
is required in most new installations unless a formal risk assessment confirms
it is not necessary.
In many domestic properties, SPDs are now considered standard practice rather than optional.
Where Is the SPD Installed?
An SPD is typically installed inside the consumer unit, connected to the main supply
and protected by a dedicated breaker.
During inspections such as
London Landlord EICR Certificates,
the presence and condition of surge protection may be noted.
Signs You May Need Surge Protection
- Frequent power fluctuations
- Expensive electronic equipment in the home
- Recent lightning strike in the area
- Upgrading your consumer unit
If you experience sudden electrical faults after a storm, you may need
London Emergency Electricians
to assess potential surge damage.
Final Advice
An SPD is a small addition to your consumer unit but provides significant protection.
In today’s technology-driven homes, surge protection is strongly recommended.
If you are upgrading your electrical installation, speak with a qualified electrician
about incorporating surge protection for long-term peace of mind.