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After my last post and having and having to re-learn some stuff can someone check and advise on a few things. Sorry if this is wrong don't hate, will make a good learning exercise as my mentor won't help me and hopefully will help others.
Specification
16 circuits- wired up to caravan hookup boxes, each unit supplied from a sub-main (calculated to worst-case scenario)
Lighting 16A+ Store 6A+ Store 6A+ Store 6A= 40A MCB 16mm single-phase SWA
x3 Circuits
canteen 40A + office 32A = 80A MCB 35mm single phase SWA
toilet+shower 63A + Spare 16a = 80A MCB 35mm single phase SWA
office 32A + spare 32A = 63AMCB 35mm single phase SWA
(cable sizes have been calculated to give less than 2% Vdrop to include 3% sub-main v drop - thus giving 5% within regs)
Total = 679 A
3 phase Split = 226 A
Sub main is to be run approx 150m to a 3 phase dist board and is run underground to supply the above circuits
Derating Factors of Sub Main
IT>In/derating factors
Taking into account 10%diversity (sorry i don't know how to do this properly i get 611.1A/203A Split)
CC= buried in ground =0.9
Ca = Thermosetting in Ambient air - 0.91 7
Other factors are 1 or n/a
IT>611.1/ 0.91*0.9 = 746.15A/249A split
choose cable to fit allowing a volt drop of 5% in total to the end of the distribution
300mm 365A 4 core SWA = 0.185mV/A/m (I'm assing this cable is huge as I've never seen a 300mm 4 core cable lmao)
gives a vd = 0.185mV/A/m*150m*249A = 6.9v
(6.9/230)*100 = 3% thus allowing a v dop of 2% on distribution
11.5V - 6.9 = 4.6V for disribution drop
Can you help with knowing how to apply the following as I have had a look but don't really get what im supposed to be doing
Diversity - I don't know the loading it is assumed worst case, but not all will be on all day every day, how would one go about tackling this? best guess?
Protection devices - for the sub-main (not that important to this application) but for future knowledge
Sub main Earthing - How would I calculate the size of a CSA earth run with the SWA separately.
Thanks all
Specification
16 circuits- wired up to caravan hookup boxes, each unit supplied from a sub-main (calculated to worst-case scenario)
Lighting 16A+ Store 6A+ Store 6A+ Store 6A= 40A MCB 16mm single-phase SWA
x3 Circuits
canteen 40A + office 32A = 80A MCB 35mm single phase SWA
toilet+shower 63A + Spare 16a = 80A MCB 35mm single phase SWA
office 32A + spare 32A = 63AMCB 35mm single phase SWA
(cable sizes have been calculated to give less than 2% Vdrop to include 3% sub-main v drop - thus giving 5% within regs)
Total = 679 A
3 phase Split = 226 A
Sub main is to be run approx 150m to a 3 phase dist board and is run underground to supply the above circuits
Derating Factors of Sub Main
IT>In/derating factors
Taking into account 10%diversity (sorry i don't know how to do this properly i get 611.1A/203A Split)
CC= buried in ground =0.9
Ca = Thermosetting in Ambient air - 0.91 7
Other factors are 1 or n/a
IT>611.1/ 0.91*0.9 = 746.15A/249A split
choose cable to fit allowing a volt drop of 5% in total to the end of the distribution
300mm 365A 4 core SWA = 0.185mV/A/m (I'm assing this cable is huge as I've never seen a 300mm 4 core cable lmao)
gives a vd = 0.185mV/A/m*150m*249A = 6.9v
(6.9/230)*100 = 3% thus allowing a v dop of 2% on distribution
11.5V - 6.9 = 4.6V for disribution drop
Can you help with knowing how to apply the following as I have had a look but don't really get what im supposed to be doing
Diversity - I don't know the loading it is assumed worst case, but not all will be on all day every day, how would one go about tackling this? best guess?
Protection devices - for the sub-main (not that important to this application) but for future knowledge
Sub main Earthing - How would I calculate the size of a CSA earth run with the SWA separately.
Thanks all