They are actually used for the same purpose. However, a fuse box is an older version of a break board, and a consumer unit is the upgraded, modern and much safer version. The older fuse box in most cases will no longer be compliant with the law. It functions inefficiently and isn’t easy to manage.
For example, if a fuse box experiences an electrical overload, the overloaded wire will melt and the circuit can not be switched back on until that wire is found and replaced. This will obviously incur costs for the owner. The modern consumer unit has a break switch which turns itself off should a faulty current be detected.
