RCD Protection for swa cable feeding garage?

[davemorris]

Im installing a fuseboard in a garage. The earthing arrangement is a tt system so oviously the garage will have its own earth rod. But does the swa cable from the double pole isolator in the meter cupboard feeding the garage have to have some sort of rcd protection because it is a TT system?

 

[not clever]

If the supply at the meter is TT then yes it does.