Single phase but 2 cable in one fuse

[Mahdi1]

Hi everyone
There is a switch board which is single phase, but when you look at the back you will see 2, 16mm cable go to the fuse(red and white). What is that for ? I haven't seen before.
And the black and blue cable goes to the service neutral link !!!
In Australia 3 phase color is Red White Blue and the neutral cable is Black

 

[littlespark]

In the uk it can be quite common to find a 4 core utilised as 2 core…. Conductors doubled up.

Could be down to design, or more likely that’s all they could get hold of.