Simplified guide to cable sizes for overseas DIY installation.

I am not sure which country you are aiming at, but separated lights and power are something of a luxury as you go a long way south or east, and leave the comfort blanket of IEC / CE and similar standards. ~As are joint boxes, twist and tape becomes common.

For the DIYer, or the local sparks as well, identifying what is there becomes much harder once things are more, as we would see it, non standard.

The option of lights on a 'power ' circuit may need to be considered. Equally lighting wire of 1mm on a 20A power radialfeeding 16A sockets and lights may also be OK in practice. 

 I'd second the recommendation of an RCD. I'm assuming you are writing for places where there are 2 wires with 220V between, but which is L or N or if you have two semi-lives may vary.

Does this country have a standard mains plug or is it a mish-mash  ?

I have seen these for example in a country with both 220 and 110V, and  correctly wired so 110v across the blades, 220 across the rods but also  sadly both sorts of wrong as well, with both round and blades at  110, or both 220.

Mike

PS image upload seems to have died. A South American socket with 2 blade slots for a US style plug, and also 2 round holes at the Europlug spacing, No earth (well why would there be !)

Thinking primarily of Ghana. 220 or 230 volts between phase and the earthed neutral.

Socket outlets include both UK types and a selection of others. Cable is often round 3 core looks like "hi tuff"  Separated lights and power seems preferable as it permits of thinner and cheaper cable to be used for the lights. Even a large home probably has no more than a dozen lamps, all low energy lamps with a total loading of under 100 watts. Low power fixed appliances are commonly connected to lighting circuits. Wall mounted fans and ceiling fans and TV amplifiers/internet routers etc.

General purpose socket outlets are used for TV sets, PCs, fridges, small cookers and small air conditioners.

Dedicated circuits are used, or should be, for larger cookers, large air conditioners, water heaters, and increasingly for washing machines.

A 30 amp service is common. I generally recommend changeover switching in such cases to avoid overloading the supply.

A surprising number of places seem to have a 1.5mm² minimum cable size ... perhaps related to the energy let-through of common types of MCBs... so for a belt and braces approach I might go for 1.5mm² rather than 1.0mm² for lighting.

Presumably radials throughout - no ring circuits?

The only obvious gap is perhaps bonding sizes? (unless we presume all other services are insulating).

    - Andy.

Probably no other services except MAYBE water which almost always uses plastic pipe.

No ring final circuits, far too complicated, too much risk of unsuitable socket outlets being fitted later. And the usual 30/32 amp OCPD wont discriminate with the service cut out.

I'd be tempted to tie cable size to the breaker rating rather than rigidly to  'lights' or 'power'.

Mike

Actually, I expect it might surprise some of the younger qualied gang in this country the things that were commonplace here not that many years back. Ironing from an iron that was plugged into a BC lampholder just for starters

Indeed, how did we all survive ? but it is a good few years , we are getting older. Earth pins on all new power sockets from about 1939, on all new lights circuits from about 1969, but these regs changes   take about half a century to work through to be common in  almost all installations in the UK.
I was in my teens when I last fitted a 2 pin plug to something, to allow use with an existing  pre-war socket, and I'm only in my 50s - well the 2nd half of them. (one of the BS 73 type with split pins - though even in the  1970s it took me a while to find someone that still had one  -  images of the kind of thing on flame port - incorrectly listed there as BS 372 - that was a later 2 pin standard and insisted on side entry cable and cable grips.).

I have memories of reading with my shadow swaying across the book in time to the iron at my grand parents place, with a Y splitter on the end of the ceiling drop cord,  so the bulb and the iron could share the lamp holder. ('overload'  'ads' 'design' all concepts blissfully unknown.) And a light in the outside loo that came on with the kitchen light, that my uncle had added as a schoolboy in the early 1940s ,with an additional  switch in the loo itself I was told never to touch when the light was on..

Mike.

one of the BS 73 type with split pins - though even in the  1970s it took me a while to find someone that still had one  -  images of the kind of thing on flame port

Ah I remember those well - I got my first shock from one. Someone had told me that the two wires were different - live and neutral - and you could only get a shock from the live. So when left to my own devices in my grandmother's house I'd spun the cover off one of those plugs while it was in a socket and tried to work out which was N and which was L - I couldn't tell by looking so tried touching one then the other - and was puzzled that I hadn't felt anything from either - yet it must have been live since the table lamp it was feeding was clearly on. After a few moments it occurred to me to touch both at the same time - at which point I still couldn't tell which was L and which was N but I did learn rather quickly that a shock does hurt rather a lot. Luckily I'd tried it with two fingers of the same hand, rather than one finger of each hand - even at the age of 5 or 6 my guardian angel was kept busy!

   - Andy.