Types of RCDs Explained by a Nottingham Electrician

Residual Current Devices (RCDs) are one of the most important electrical safety components found in homes and businesses across Nottingham. They are designed to protect people from electric shock and reduce the risk of electrical fires.

However, many properties in Nottingham—especially older homes—still have outdated RCD protection that may no longer meet current UK wiring regulations (BS 7671).

In this guide, our qualified Nottingham electricians explain the different types of RCDs, what they are used for, and how to know which one is right for your property.

What Is an RCD and Why Is It Important?

An RCD monitors the flow of electricity through a circuit and instantly disconnects the power if it detects a fault. This usually happens when electricity leaks through an unsafe path, such as damaged wiring or contact with a person.

RCD protection is essential in:

• Nottingham homes and flats

• Rental properties requiring EICR certificates

• Commercial premises and offices

• Outdoor circuits and garden electrics

If your property does not have suitable RCD protection, it may fail an electrical safety inspection.

The Main Types of RCDs Used in Nottingham Properties

Type AC RCD (Outdated in Many Homes)

Type AC RCDs respond only to alternating current (AC). These were common in older consumer units installed many years ago.

Where they are found:

• Older Nottingham properties

• Outdated fuse boards

Important:
Type AC RCDs are no longer recommended for most modern electrical installations and are often flagged during EICR inspections in Nottingham.

Type A RCD (Recommended for Modern Homes)

Type A RCDs can detect both:

• Alternating current (AC)

• Pulsating DC currents produced by modern appliances

Common in Nottingham homes with:

• Washing machines and tumble dryers

• Induction hobs

• Modern kitchens and extensions

This is now the minimum standard for most domestic properties.

Type F RCD (Heat Pumps & Inverter Equipment)

Type F RCDs are designed for appliances with variable speed drives.

Typically required for:

• Heat pumps

• Air conditioning systems

• Inverter-driven equipment

As more Nottingham homes move toward energy-efficient systems, Type F RCDs are becoming increasingly common.

Type B RCD (EV Chargers & Solar Systems)

Type B RCDs offer the highest level of protection and are mandatory in certain installations.

Used for:

• Electric vehicle charging points

• Solar PV systems

• Commercial and industrial equipment

If you are installing an EV charger in Nottingham, a Type B RCD (or equivalent protection) is often required to remain compliant.

RCBOs (Best Practice Consumer Unit Protection)

An RCBO combines RCD protection and circuit breaker protection into a single device.

Benefits:

• Each circuit is protected individually

• Fewer power outages during faults

• Improved safety and reliability

Most modern consumer unit upgrades carried out by Nottingham electricians now use RCBOs as standard.

Why Having the Correct RCD Matters in Nottingham

Incorrect or outdated RCD protection can result in:

• Frequent nuisance tripping

• Increased safety risks

• Failure of EICR inspections

• Non-compliance with current regulations

Many electrical faults found in Nottingham properties are linked to incorrect RCD selection or ageing consumer units.

Do You Need an RCD or Consumer Unit Upgrade?

You may need an inspection if:

• Your fuse board is more than 10–15 years old

• Your consumer unit contains a Type AC RCD

• You are a landlord requiring an EICR in Nottingham

• You are adding an EV charger or new circuits

A professional inspection can confirm whether your system is safe and compliant.