You and your home are protected several different ways throughout your electrical installation, all of these protections each serve a different purpose and together they keep you and your family safe.

This is the basic insulation of the cables, meaning that if you were to touch a cable, you would not receive an electric shock.

This is a device that will trip off or blow if too much current is passed through it. This could be in the form of a device at the beginning of your circuit, called an MCB (miniature Circuit Breaker) or an RCBO (Residual Current Circuit Breaker with Overcurrent Protection). It could also be a fuse or fuse wire in older installations.

This is a device that will trip off if there is a fault on the system, MCB’s, RCBO’s and RCD’s (residual Current Detector) all do this.

RCD’s are labelled as “additional protection” in some circumstances, which would imply that they are not as important, this is not to be the case. An RCD is a device this trips off at a measured current that is believed to be a “safe” amount, this amount is a tiny 30ma, and it trips off in 40 milliseconds. This is also believed to be a safe amount of time and is a prescribed amount that relates to the time it takes your heart to beat.


An RCD is there purely to prevent injury, death and Fire.

SPD’s (Surge Protection Devices) are a device that goes at the beginning of your installation to make sure that no “spikes” of electricity can surge through your installation, potentially damaging parts of the installation, or appliances that are plugged into it.

This is a new requirement that has been created by the most recent electrical regulations, AFDDs (Arc Fault Detection Device) will now need to be installed on each circuit, these devices detect any arc in your installation, this could be a broken cable, a lose connection, a faulty device that is plugged in/installed. This device very cleverly picks these up and isolates the circuit without picking up other devices that have components in them that have arcing in them.

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Alto Electrical are qualified, competent and registered with the NICEIC. We are insured to £10Million, are reputable, approachable and offer great value for money.
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