Electrical Consumer Unit 101: What it is and Why it's Used

An Electrical Consumer Unit, also known as a Distribution Board or Fuse Box, is a vital component in any electrical system. It serves as the central hub for distributing electricity within a property and protects electrical circuits from overloading or short-circuiting. Understanding the purpose of this unit and how it operates is crucial for ensuring the safety of electrical systems and preventing damage or injury. This article aims to provide a comprehensive guide on Electrical Consumer Units and explain why they are an essential aspect of modern electrical systems.

What is an Electrical Consumer Unit?

The electrical consumer unit is the main distribution box where electricity is distributed and contains electrical protection and control elements. The consumer unit is positioned between the electricity meter and the electrical devices in domestic applications. All protection and control operations are located in this box.

The electrical consumer unit is also referred to as:

fuse box
fuse board
consumer box
plastic/metal enclosure

The electrical consumer unit is the main control point for the electricity in a house. The elements that feed and protect all the appliances in the house are located in this box. It provides the safe operation of electrical devices in boxes and protects all devices from impact and dust. The consumer unit enclosure must be manufactured from a non-combustible material to limit the spread of fire. For your safety, it is useful to know the location of the fuse box in your home or workplace.

Why is the electrical consumer unit used

How to choose an electrical consumer unit?

The selection parameters of a consumer unit are:

Mounting type and location

First, you have to decide whether the consumer unit will be flush or surface mounted. The flush-mounted model will look more elegant. If you do not have flush mounting options, the surface-mounted model will be easier in terms of installation. You can determine the model of your distribution unit according to the location you will install it.

Material

It is very important whether your consumer unit is halogen-free or not. It should have a structure that prevents the spread of toxic gases in case of fire. If you wish, you can also choose metal types but you will pay more in terms of cost. A plastic-halogen-free consumer unit will be sufficient. You should also check the fire resistance temperatures of the cover and body.

Dimensions

You should determine the size of your electrical consumer unit according to your space, and which elements you will use in the box. When choosing a consumer unit, you will hear terms such as 12 modules, and 24 modules. Let us remind you that the module concept is the width of the miniature circuit breaker you use. If you prefer a 12-module MCB, you can install 12 pieces of 1-pole MCBs side by side. You should determine your box dimensions according to the number of elements in your installation. Important reminder: In case of adding extra equipment to the building in the future and absorbing the heat emitted by the fuses, we recommend that you leave a few module spaces. Thus, you will have extra space for any future additions.

Door

The door of the enclosure can be opaque or transparent. When you use an opaque door, the elements inside will not be visible from the outside. Transparent doors are preferred in terms of security. A problem that will occur inside the box can be seen more easily with the transparent doors. Decorative models can also be preferred according to the needs of the area. (For example, you can choose a model for an art gallery that is compatible with the atmosphere)

Protection class

You must prevent dust ingress into your unit. Equipment life will be longer and everything will work safely. An IP40 fuse box will do the trick.

Din-rail

Be careful if there is an internal din-rail inside the consumer unit. Some manufacturers only sell the enclosure.

Cable entries

Examining the cable entries and holes that will enter the unit will provide you with an advantage during installation.

How to choose an electrical consumer unit

Devices Can Be Available in the Consumer Units

The answer to this question varies from application to application. Still, let’s list the most used elements:

Miniature circuit breakers
Residual current relays
Busbars or dispenser units
Din rails
Jumpers
Contactors, impulse relays, arc protection devices, surge protectors, etc., as required.