"Mark" wrote
| Is it ideal to have the lighting ciruit in a big kitchen around
| 600watts in total on a ring circuit like a mains ring or not?

No. It's certainly not a standard circuit and nothing would be gained.

The standard 5A/6A lighting circuit is enough for 12 ordinary points (each
point must be considered as minimum 100W, or actual load if greater).

| and how would you incorporate a switch into the loop.

You can't switch parts of the ring, or it would stop being a ring. You can
only switch spurs from a ring, which is why it's a bit pointless using one
for lighting. Unless of course you are lighting something the size of a
football stadium, when it might be useful to use a ring to reduce the cable
size. In that case though the whole ring would be switched on/off. And it
wouldn't have a 6A MCB on it either.

Owain