Consumer Units

The consumer unit is made up of numerous pieces, including a mains switch, residual current devices (RCDs), and circuit breakers, and is responsible for powering all of the circuits in your home.

A consumer unit's principal purpose is to safeguard your home from an electrical hazard.

According to BS 7671, all RCDs should be tested at least once a quarter to confirm that they are still functional. The end user can perform this by pressing the 'T' or 'Test' button on the test device (usually a pushbutton).

Yes, consmer units must be installed in domestic environmnets. 

Consumer units in domestic premises must be made of non-combustible materials or housed in a cabinet made of non-combustible materials, according to BS 7671:2018 regulation 421.1.20.

We have a wide range of metal consumer units which are available for next day delivery. The metal material is designed to create fire resistant consumer units.

RCD protection is now required on most circuits in a household installation. When fitted in an AC final circuit, all luminaires within domestic (home) premises must be protected by a 30 mA RCD, according to BS 7671:2018 Regulation 411.3.4.

An MCB is a type of electrical switch that operates automatically. Miniature circuit breakers are designed to protect an electrical circuit from harm caused by excessive current. To protect against electrical failures and equipment failures, they are designed to trip upon an overload or short circuit.

In simple terms, an RCBO is a Residual Current Operated Circuit Breaker with Overcurrent Protection that combines the use of an RCD and an MCB. They're a crucial part of your consumer unit since they prevent overloads, over currents, and electric shocks while also limiting tripping.

You should not attempt to replace your own consumer unit unless you are a certified electrician. The use of a certified professional for this type of electrical work is required by law.

At Meteor Electrical, we supply a wide range of consumer unit accessories to meet the requirements of your consumer unit. We have isolators, control devices, MCBs, contactors, busbars, RCBOs, RCDs, switchfuses, din rails and surge protections.

Whatever consumer unit accessory you need, we have it. Chat to our sales advisors on the live chat if you can’t find the consumer unit accessory you need to complete your consumer unit. 

A Split Load Consumer Unit, also called as a High Integrity Consumer Unit, is a type of consumer unit that has both RCDs and RCBOs. We supply a wide variety of split load consumer units from LIVE Electrical.

At Meteor, we have mini consumer units and large consumer units. Our range of mini consumer units are available from 2 way up to 18 ways. Our large consumers units are available from 22 way up to 75 ways.

1. Main Switch 

Most people confuse the main switch for the domestic consumer unit, but the main switch is only one part of the whole device and a key component at that. The main switch is a central switch that controls the entire power supply within a single property to that the consumer unit is attached. 

If the main switch is turned on, it is only then the power will be on, and if you turn it off then the power will be disconnected and turned off. While other components such as the RCDs and circuit breakers can be turned off automatically, the main switch has to be turned on or off manually. 

Usually, there isn’t a need to frequently switch it on or off but in some cases, it may become necessary. For example, if there is repair work to be done on the power supply then the main switch will have to be turned off. Disconnecting the power supply is what will ensure your safety.

2. RCD – Residual Current Devices

The safety switches present inside an MCB consumer unit that constantly monitor the power supply are called the Residual Current Devices (RCDs). The entire power supply of an area (like a building or factory, for example) is split into several circuits. Various electrical appliances are connected to these circuits through which electric current passes in order to make them work. 

Every RCD has its own power rating and if the power supply crosses that rating, it means an overload is occurring and so the RCD will automatically turn off. When a RCD turns off, it has tripped. The power supply in the entire circuit will disconnect as a result. RCDs usually have a rating of 30 milliamps, and anything above this is dangerous to humans. 

RCDs are a kind of smart device with the main purpose of preventing electrical hazards. They work by detecting any abnormality in the electrical circuit and turning it off entirely; this could be any abnormality occurring in the pathways of the electric current, such as you touching the live wire. Thanks to this, it saves the user from deadly electric shocks and severe injuries.

3. Circuit Breakers

Circuit breakers and RCDs work with the same mechanism – both are safety switches in any modern electrical MCB consumer unit and their main purpose is to prevent hazards. 

However, there is a thin line that differentiates the two; a whole RCD can control multiple circuits at a time, a circuit breaker can only control one circuit or section of a large circuit. This is why you may find several circuit breakers scattered around any area with an electrical circuit installed. 

Similar to RCDs, circuit breakers have a specific electric rating where if the electricity flows beyond it, the circuit breaker will trip and disconnect the current entirely. This prevents accidents and electrical appliances connected to the circuit from damage. Circuit breakers are also at times referred to as MCBs (miniature circuit breakers). 

Circuit breakers/MCBs trip in some specific cases such as overload and overcurrent. Overload happens in the case you plug in too many appliances into the same current and the total exceeds the MCB’s electric rating. In this case, the MCB will trip and turn off the circuit. 

Overcurrent on the other hand is when the electricity flow exceeds its intended limit and the MCB consumer unit trips to disconnect the circuit. This usually occurs because of something like faulty wiring.

Most types of consumer units have the same functions, and they differ mainly in the case of their size and magnitude of capacity. Here are some common types of consumer units you should know about. 

Split Load Consumer Unit

A split load consumer unit usually contains a main switch and an RCD where the MCBs are placed on the RCD side and RCBOs on the main switch side. It is also referred to as a high integrity consumer at times. The split load consumer unit is also one of the safest panel boxes compared to other types because of the protection it gives.   

A split load consumer unit has overload and short circuit protection, as well as an earth leakage protection on the RCD-protected side of the device. If you are looking to buy a split load consumer unit, it is better to get one that has more capacity than what you require. 

Dual RCD Consumer Unit

A dual RCD consumer unit comes with the main switch and two RCDs – the RCD's are meant to control and protect the circuits connected through associated single pole MCB circuit breakers. It is one of the cheaper solutions compared to others. They are designed to enable the configuration of two banks of circuits. 

RCD Consumer Unit

A RCD metal consumer unit are smaller in size and capacity and is good for when you want to use separate domestic consumer units for your garage or storehouse. You won’t need to get a large consumer unit. 

A RCD mini consumer unit is supplied with at least one RCD which protects a bank of circuits from earth leakage. RCD consumer units will do a great job at ensuring that the power supply to all circuits is cut automatically if any leakage is detected.

A weatherproof consumer unit is actually a kind of distribution board. In fact, all consumer units are distribution boards, but not all distribution boards are consumer units. In the UK in particular, you can find consumer units as the most common type of panelboards. 

A 2 way fuse board is a mini consumer unit that is ideal for smaller outbuildings where a large consumer unit would be inconvenient. A 2 way fuse board offers two outgoing ways for device configuration and various options are available according to what the installation requirements are.

To find the most suitable location to place your plastic consumer unit, think about accessibility and space; avoid enclosures and confined spaces. It should be easy to reach the 1-way consumer unit with sufficient space around the domestic consumer unit so operating switches and protective devices such as RCDs can be accessed. 

Electricians will have to access the MCB consumer unit and so would require enough space for them to carry out inspections and maintenance without hindrance. Any area that is awkward to reach should be avoided, and the accessibility needs of the disabled and elderly should also be taken into account when deciding the placement location.

Outdoor locations should generally be avoided and should be kept at a mounting height preferably so it is out of reach of young children. A safe height for a 5 module consumer unit can be between 1350mm and 1450mm above floor level. If an outdoor area is used then a weatherproof consumer unit should be used along with the required equipment and protection. 

Count every circuit you need today, add the space taken by the main switch, RCDs and any surge protection device, then leave two or more spare ways for future circuits. Note that a module is a unit of DIN rail width, and some devices use two modules. Oversizing slightly costs little and avoids adding a second board later.

Metal clad units meet the UK requirement for domestic consumer units to be housed in non-combustible enclosures, introduced to reduce the spread of fire from a board fault. This requirement sits within BS 7671, so check the current edition and any local rules in Ireland. Our Live Electrical metal enclosures are designed with this in mind.

Sometimes, but it depends on the board design. Some split load boards can take RCBOs in place of MCBs, while others need busbar changes or a different enclosure. Check the manufacturer's guidance for your model, and if it cannot be adapted, a main switch enclosure fully populated with RCBOs is usually the cleaner option.