Originally posted by Ken C
many thanks mark for the info. i always wondered what the acronyms mean. (what about the C in TNC-S?).
i agree stick with supply earth. i have two 10mm^2 radials from the consumer unit to the hifi, presumably this means i have to run 2 THICK cable earths from CU to each radial outlet. since my radials are wired with 45 amp rated T&E, i would assume (perhaps wroingly) that the earth of this cable is rated quite close to 45amps (do you know the actual rating? -- its a bit thinner than the L/N wires)
while we are talking about outlets, do you know where i can get an unfused/unswitched triple socket? the plugs will be fused, so we are still safe.
Originally posted by MarkS
C - earth & neutral conductors combined.
I'm unclear by what you mean by radials? Spurs?
Apropos your earth cable, current rating is not the issue but resistance minimum value. However, judging by your cooker cable spec I think your into the realm of splitting hairs...
Triple unswitched - try current Screwfix catalogue(no 77) page 177 Part No D12398 - Select 3g @ £6.95 each inc vat.
Want to get serious? Go 16A industrial.
Mark
Originally posted by MarkS
If you have type B mcb's for your hifi mains feed change it to type C as this deals better with current spikes/surges.
BTW, a 10mm^2 conductor(pvc insulated), clipped fixing, has a domestic rating of 65A...ie 65x230=14.95kVA which is more than adequate for a domestic hifi....
Mark
Originally posted by Ken C
radials vs spurs -- for what i have, a single cable from CU to socket outlet, i gather the correct name is radial rather than the commonly 'mis'used "spur".
ah, OK impedance. i thought the cable has to be able to handle likely mag of earth fault current as well?
many thanks for source of triple sockets.. yes, i want to get serious splitting hairs -- what this 16A industrial and where to get it ?
Originally posted by Ken C
mark, many thanks. will check what type mcb i have -- presumably this will be obvious from looking at it.
65 amps!! seriously over-rated. sounds bloody good though... not too sure i fully understand why.
Originally posted by MarkS
The mcb will eg show on the front it's a B32 ie it's a 32A type B...
Think of the fat radial cable a "breather" tube for your amps. If you have a six pack setup of, say, 500VA transformer in each amp plus, say, 200VA for the other bits in your system... = 3200VA total, cf that with the 14.9kVA capability of your supply cable...I don't think your sound system would get weezy... ;-)
Mark