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Whether at home or work, we are surrounded by computers, smart phones and TV’s along with our dependency upon the use of appliances such as washing machines, dishwashers and tumble dryers and systems such as fire or intruder alarms. These devices can all be vulnerable to transient over-voltages, which can significantly reduce an equipment’s lifespan through degradation and damage. Over-voltages can come from sources such as lightning or switching on or off inductive loads.

Protection can be given to help prevent such damage through the inclusion of ‘Surge Protection Devices (SPD). This protection isn’t always mandatory but they’re becoming more of the norm to help protect valuable data and equipment.

One of the threats to devices is lighting. A discharge from lightning near a power supply cable could generate a significant over-voltage transient and cause damage.

Surge protection devices are classified according to their standard into different types. There are three types of surge protection device:

When installing a surge protection device, you should refer to BS 7671 for the correct regulations.

Making sure a connection is correct is vital when using surge protection devices. To obtain the maximum protection from the SPD, the connecting conductors should be kept as short as possible. This is to minimise any additive voltages on the connecting cables.

Surge protection devices can offer a visual indication to help with the inspection and testing process. Usually colour coded, if a green light is displayed then this means the device is operational. If a red light is displayed however, it means that the device has reached its end and needs replacing.

We have a range of surge protection Consumer units and Retro fit boards from Hager, Contactum & Cudis to help make your next installation even safer.

Things you need to know about Surge Protection Devices

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