Installation requirements assignment

[Blacksun]

Hello there. I am currently studying the city and guilds course in electro-tech and need some help with an assignment I have received.
I would appreciate a dummy explanation as i'm struggling to grasp a few things.

The assignment starts off with the following 10 questions/tasks for each circuit in a house:

1) Calculate the designed current for every circuit.
2) Apply diversity where required
3) Calculate the minimum cable size required for every circuit
4) Calculate the voltage drop
5) Determine the type of circuit you are going to run
6) Draw a plan of the premises
7) Determine the maximum demand
8) Determine the type of CCU required
9) Determine the type of protective devices required
10) Determine the rating of the main service head cut out fuse

"A customer has a semi- detached three bedroom house which he would like to have re-wired. He would also like to have his garage 20m external to the property wired for lighting and power."

It is a TN-S 230V single phase.

Kitchen

Lighting: 2 twin fluorescent lamp fittings. Each tube is rated at 50W= 100W per unit.

Power: 8 twin socket outlets switched.

Cooking: One 6kW hob and one 10kW cooker.


I know it's a lot, but if I can fully grasp this, a lot will have become clearer to me.

Any help would be greatly appreciated.

Cheers.

 

[Sparky Ninja]

What books have you got access to?

 

[Blacksun]

The 17th edition regs, onsite guide and the level 2 and 3 trevor linsley books.

 

[armbands0]

Lights Ib = 200x1.8(p.f. osg p.96) = 1.56A
Power, decide on type of circuit Q5, A1 Ring final or A2 radial (p158 osg) either circuit Ib = 32A
Cooker+hob, Ib = 16000/230 = 70A
Garage Ib depends on potential loads.
But if you install SWA to a GCU with 2 mcb's a 20A radial and a 6A lighting you can assume a load of 26A

Diversity (p.97 osg) cooker first 10A plus 30% of remaider so 10 + (30% of 60A) = 10+18 = 28A (if CCU Q8 has no socket, but if you choose one with socket add 5A)

I have to go now but maybe this has given you a start, you are not alone.

 

[Blacksun]

Lights Ib = 200x1.8(p.f. osg p.96) = 1.56A
Power, decide on type of circuit Q5, A1 Ring final or A2 radial (p158 osg) either circuit Ib = 32A
Cooker+hob, Ib = 16000/230 = 70A
Garage Ib depends on potential loads.
But if you install SWA to a GCU with 2 mcb's a 20A radial and a 6A lighting you can assume a load of 26A

Diversity (p.97 osg) cooker first 10A plus 30% of remaider so 10 + (30% of 60A) = 10+18 = 28A (if CCU Q8 has no socket, but if you choose one with socket add 5A)

I have to go now but maybe this has given you a start, you are not alone.

That's a brilliant start.

Thank you!