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Charles_V View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Charles_V Quote  Post ReplyReply Direct Link To This Post Posted: 11 July 2007 at 12:20pm
Originally posted by HansA HansA wrote:

Fuses are not in the pluggs but in the equipment.

nice. so if you have a problem with the insulation on the cable between the wall and the equipment, there is nothing but the breaker on the ring main..

hmmm. toasty.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote HansA Quote  Post ReplyReply Direct Link To This Post Posted: 11 July 2007 at 12:24pm
Well. When does the main cable fail? That have'nt happend to me yet in this lifetime.

And the main fuses are automatic. So, It's just to flick it up again when the problem is sorted.
�*�o�O�o�*�*: HansA, The FUBAR sound technician :*�*�o�O�o�*�
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Post Options Post Options   Thanks (0) Thanks(0)   Quote levyte357 Quote  Post ReplyReply Direct Link To This Post Posted: 11 July 2007 at 12:50pm
Originally posted by HansA HansA wrote:

<SNIP> Get with the program. Start driving on the right
 
Why would we want to drive on the wrong side of the road?
 
Almost as bad as giving up Real money like Sterling, for "Yoyo's" .


Edited by levyte357 - 11 July 2007 at 12:51pm
"Who am I? I'm the guy who does his job.. You must be the other guy".
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HansA View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote HansA Quote  Post ReplyReply Direct Link To This Post Posted: 11 July 2007 at 7:49pm
Cause your are incompatible with the rest of the world ;)
-
Took me a week to get used to. I almost got hit several times crossing the road. Cause i forgot i was in England and not Norway. Ok i was a bit drunk to.
�*�o�O�o�*�*: HansA, The FUBAR sound technician :*�*�o�O�o�*�
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Post Options Post Options   Thanks (0) Thanks(0)   Quote josh Quote  Post ReplyReply Direct Link To This Post Posted: 12 July 2007 at 6:37pm
thats the best bit about england....the fact that we are so different, that we use metric and imperial units, have our own currency and drive on the left.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote DavidBLt Quote  Post ReplyReply Direct Link To This Post Posted: 12 July 2007 at 8:34pm
Back to the topic, (well, sort of…) you guys can still get more power from your 240V/13Amp service than we can get in the states.  A ‘standard’ 120Vac outlet over here is only going to give you 15 amps for a short while before the breaker trips(and who knows where you'll find the breaker-box).  In most commercial settings; 20 amp outlets are common, but still very restrictive comparatively.

Then again, if you’re going commercial, you’re going to a dedicated, isolated service anyway.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote kevinmcdonough Quote  Post ReplyReply Direct Link To This Post Posted: 13 July 2007 at 3:54pm


OK

Disclamer: Here's how i've always understood UK power, though i'm not a spark so could be wrong and any advice taken from here should probably be double checked first.



Each individual socket in your house can handle 13amps. This value was decided in the past as being the most amount of current that a normal person will need for any single socket/device, and so the sockets plastic and components are designed to handle this without melting or failing. The 13amp fuse was chosen to match this so that it would blow in a controlled way before the plug melted in a dangerous way. It is possible to do all sorts of tricks to increase the fuse like replacing it with a piece of wire or just a bigger fuse, but then you risk more than 13 amps flowing in the socket and it causing damage.

The individual sockets are all connected to a ring main. Each ring main in the house runs back to your main distribution board, and the ring as a whole will be rated at the amp value of whatever breaker it is attached to, which is normally 32 amps (and this is what I’ll reference for the rest of the example). This limit is designed to protect the wire that the ring main is connected/made with from receiving more current than it can handle and melting or being damaged within the walls of your house.

So to recap, the total current for all sockets on a given ring main will be the breaker value, usually 32 amps, while any individual socket on that ring can take a max of 13amps.


Now this raises the question, how come you can have a lot of sockets on a single 32amp ring?  In theory, if 3 of the sockets were running at the 13 amps that would be 39amps and you would be over the limit for the wring as a whole.

Having lots of sockets on a ring is done because it is assumed that they won’t be used at 13amps, or anything close. Almost all household devices will only use a couple of amps if that, and even then it is usually not a consistent draw but varies. The only ones that come close to using larger currents would be “high power for a short time” devices like kettles or maybe large microwaves that will only be on for a short time. Bigger things like cookers, power showers etc etc will usually be on their own breaker so they don’t affect the ring main.


But for us sound guys who use big fat current drawing devices (i.e. 3000w and above amps ) we will actually be getting close to the 13amp limit for a single standard socket.

Now one very real option is to simply replace a 13amp wall outlet with a 16 or even 32 amp cee-form outlet. In the end they all do the same job, i.e. provide metal pins to allow the electricity to travel from the ring main to the device. The only real difference between the cee-form ones and normal sockets is that they are designed with better plastic/metal components that can handle the higher current safely.

That outlet would be able to handle 16 or 32 amps, and all the others still 13, as long as the total on the ring circuit doesn’t exceed our 32amp breaker.

However, remember our initial assumption for having lots of sockets on a single ring, which was that they only actually recieve a much smaller amount or current in real life. Well this doesn’t apply now because the only reason for changing a 13amp socket to a 16amp one would be because we already know we are close or over the 13amp limit on a single socket. So we can only really safely put one or two of these sockets on the ring before the 32amp limit will be exceeded.

In most cases however, as stated, this won’t be needed. The amp will only be drawing its maximum current when running full tilt at 2 ohms with extremely consistent signal. Even in the cases where your hammering it hard at 2 ohms, the nature of music means that although the peaks may reach high amounts, the average will usually be lower and under 13 amps.

However if using your amps in this way is going to be a regular thing then you may wish to look into getting another ring main put in at your venue (or house), with only one or two 16 or 32amp cee-forms on it, and then having a distro made up to power your rig from these.


k




Edited by kevinmcdonough - 13 July 2007 at 4:05pm
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gingerbiscuit69 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gingerbiscuit69 Quote  Post ReplyReply Direct Link To This Post Posted: 13 July 2007 at 4:07pm
or at your local venue where u regularily use stuff... if you regularily use 13amp+ drawing amps at home and run rigs requiring 32amp supplies, u may find yourself getting shot!!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Carl- Quote  Post ReplyReply Direct Link To This Post Posted: 14 July 2007 at 12:03am
The real difference between UK and mainland seems to be that we (in Holland anyway) have no 32A. ring supply, but only 16A. That covers the danger of burning out the mains cable. It is not protected by a 13A. fuse, but by a 16A. one, the difference is small i suppose
Usually there are 3~8 circuits to power the house, there are 6 in my house, all 16Amps. The main incoming fuse in my house is 35Amps, only one phase, and in a sealed box. This is common in Holland, allthough there are houses that have 3-phase supply, and i have seen 18 circuits in a large house. Bit overkill maybe......
The few times that i have visited the UK, i saw that you usually have a double walloutlet, that mans you can use 26Amps in a simple way.
Okay, it makes wiring and spreading the load a little more difficult, but not much.
People who think they know everything are annoying to us who really do.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote HansA Quote  Post ReplyReply Direct Link To This Post Posted: 14 July 2007 at 6:09am
The circuits are usually divided up between rooms. Where all the outlets are in parallels.
En example could be.
:Circuit 1: Kitchen
:Circuit 2: Hall, bedroom 1 and bedroom 2
:Circuit 3: Livingroom
:Circuit 4: Bathroom

Here in Norway newer systems would have all 16A. In older systems usualy 10A in the Circuit 2 and maybe 3 and 16A in 1 and 4.
But the mains would probably only be 32A anyway.
If it has the size and the need then there could be double and triple 32A on the mains.
There would be no problem running 32A circuits in a house, with the mind on FIRE, if the weiring was good enough. thicker cables = more power capacity.

As far as i know you usually have 3-phases 400V in the streets of UK.
Here you take out 230v 3 times between the different phases. Giving you (not sure of the A) 3x32Amps 230V. Then you funny guys install 13A fuses and 13A weiring??? UK=Alot of funny solutions.
�*�o�O�o�*�*: HansA, The FUBAR sound technician :*�*�o�O�o�*�
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gingerbiscuit69 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gingerbiscuit69 Quote  Post ReplyReply Direct Link To This Post Posted: 14 July 2007 at 11:08am
and heres my house, with 128amp in, no RCD unit, just four 32amp fusewire fuses ... one for kitchen, one for downstairs ring, one for upstairs ring and one which im yet to find out where it goes...

nice early victorian house, origional electrics from when they were installed, no electrician will touch anything!!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Carl- Quote  Post ReplyReply Direct Link To This Post Posted: 15 July 2007 at 10:54pm
No Hansa, as i think that i have seen it, they install wires thick enough to carry 32 A. (4qmm??)This means that (in theory)you can take the full 32A. of a single outlet. These are not made for 32A. so you would melt/burn it, the max. fuse in a plug is 13A, and all plugs are supposed to be fused.
The electrical system in GB may look funny to us, but it certainly is far from stupid!
People who think they know everything are annoying to us who really do.
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