What is SPD and do I need one?

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SPD is known as Surge Protection Device are used to protect the electrical installation, which consists of the Consumer Unit (Fusebox), Wiring System and Appliances, from electrical power surges known as transient overvoltages. Transient overvoltages are short duration, high magnitude voltages peaks with fast rising edges, commonly referred to as Lightning Surges.

SPD is now built-in Electric Vehicle Chargers, Solar Generation Systems and many more. Your home appliances and conductors (wires) in walls, floors and ceilings are part of your Electrical Wiring System of your Home or Business.

SPD protects data on your computers, laptops and other crucial or life saving devices. This little device keeps your electronics from getting damaged in a power surge, usually storm related, by redirecting unexpected increases in voltage away from delicate equipment. Even without a storm, smaller, less noticeable power spikes can shorten the life of your devices.

There are a number of different types of SPDs available, so it is important to choose the right type for your needs. SPDs can be installed in a variety of ways, so it is also important to consult with a qualified electrician to ensure that they are installed correctly.

Here are some of the benefits of using a surge protection device in the UK:

The consequences of a surge

Without adequate protection the greatest consequence is a risk to human life, particularly in circumstances where medical equipment is involved and could be damaged. Secondly, there is the potential downtime in production e.g. in a workshop, retail outlet or office.

Type 1 SPD

The Type 1 SPD is recommended in the specific case of service-sector and industrial buildings, protected by a lightning protection system or a meshed cage.It protects electrical installations against direct lightning strokes. It can discharge the back-current from lightning spreading from the earth conductor to the network conductors.

Type 2 SPD

The Type 2 SPD is the main protection system for all low voltage electrical installations. Installed in each electrical switchboard, it prevents the spread of overvoltage's in the electrical installations and protects the loads.

Type 3 SPD

These SPDs have a low discharge capacity. They must therefore mandatorily be installed as a supplement to Type 2 SPD and in the vicinity of sensitive loads.

For more information on electrical safety and how to get regular maintenance, testing and protection please get in touch.

You must check if your electrician is qualified and also registered to carry out Domestic work under Part P and he must be registered with one of the 5 main organization, which you can check on the Competent Person scheme here.

Please Feel free to contact Cavendish Eletricals & Services and send us an enquiry through our web page. If you have any question you can email us to info@cavendishelectricals.co.uk or you can call us on 015 3648 3348.

We cover a wide range of areas: Northamptonshire, Leicestershire, Buckinghamshire, Cambridgeshire, Bedfordshire, Hertfordshire and Greater London (M25).