Is it really 100 amp

[johnad]

I have a cutout that states it is 100 A
It's in a cottage with a overhead supply and to be honest the cables at the post just outside my cottage look quite thin ? I would guess about 16mm
Surly they wouldn't put a 100a cutout on the end of a cable that will not handle the load ???? (would they).

Also the earth rod has a 6mm cable connecting it surely not big enough. ?

 

[XtraRaptor]

Just because the cutout is capable of carrying 100A there could be a smaller fuse inside it.

 

[RF Lighting]

Depends.

Often the cutout will say 100A on the outside, yet it might contain a 60A, 80A or 100A fuse.

16.0mm² might be ok for a 100A supply. It is upto the DNO to determine this.

As you have an earth rod, you must have a TT supply. This will mean that due to the impedence of the rod, and also the RCD protection to your installation, that the most current the earth wire will ever have to carry is a few amps in a worst case scenario, but more likely it will be a couple of hundred mA.

BS7671 permits the main earth on a TT supply to be as small as 2.5mm² as long as it is protected from mechanical damage.