M
mrdesigner35
I am building a granny flat for my increasingly wobbly mother in our garden. All proceeds well so far except it has obviously cost more than expected!
My electrician suggested to save ourselves money, we can put in the three core armoured cable that he will attach to the electrical supply in the main house and then to the consumer unit. He is connecting everything. The granny flat is 30metres max (more like 26m) from the main supply. Of this 5m is buried 30mm under ground, 5m outside walll mounted and 16m inside, wall mounted.
He has suggested a 25mm2 three core armoured cable, but also possibly a 16mm2 but it depends on the loading.
In the granny flat there will be a ring main with 7 double sockets (2 in the kitchen - toaster kettle, 4 living room -tv dvd modem light, 1 bedroom -light), a shower electric heated (just an average mid range one- 10Kw), a 15ltr under counter water heater in the kitchen for the basin and kitchen sink - 4Kw, two wall mounted 1500W radiators, a heated towel rail, bathroom extractor fan, kitchen extractor fan, lighting circuit with 9 ceiling lights in total, and of course a small oven - 3Kw.
Please can you tell me how to calculate what size three core cable armoured cable. We are watching the pennies!
Thank you in advance - it sounds like homework I know. I am fascinated to know how it is worked out. She lives alone - but might get a fella (she says!)
My electrician suggested to save ourselves money, we can put in the three core armoured cable that he will attach to the electrical supply in the main house and then to the consumer unit. He is connecting everything. The granny flat is 30metres max (more like 26m) from the main supply. Of this 5m is buried 30mm under ground, 5m outside walll mounted and 16m inside, wall mounted.
He has suggested a 25mm2 three core armoured cable, but also possibly a 16mm2 but it depends on the loading.
In the granny flat there will be a ring main with 7 double sockets (2 in the kitchen - toaster kettle, 4 living room -tv dvd modem light, 1 bedroom -light), a shower electric heated (just an average mid range one- 10Kw), a 15ltr under counter water heater in the kitchen for the basin and kitchen sink - 4Kw, two wall mounted 1500W radiators, a heated towel rail, bathroom extractor fan, kitchen extractor fan, lighting circuit with 9 ceiling lights in total, and of course a small oven - 3Kw.
Please can you tell me how to calculate what size three core cable armoured cable. We are watching the pennies!
Thank you in advance - it sounds like homework I know. I am fascinated to know how it is worked out. She lives alone - but might get a fella (she says!)
