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levyte357 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote levyte357 Quote  Post ReplyReply Direct Link To This Post Posted: 09 July 2007 at 1:06am
Originally posted by ceharden ceharden wrote:

Just because it has a 16A outlet, doesn't mean there is 16A available!

It should probably have a 16A Ceeform inlet too if it's really for site use.

It's probably just an RCD in a big box you can't break/loose etc.  I doubt it does any more than the ones you get built into a 13A socket.



Found this one also.

http://www.vanstockuk.co.uk/acatalog/Site_Safe_240V.html#a903

This does state max load 3840 watts.
 
EDIT:This is same supplier as previous ebay advert, just bit more detail in here.
 
Spoke to supplier, and as ceharden stated, the unit doesn't provide 16A from 13a socket, just provides protected way of delivering 13amp to 16amp connection; i.e power tools.
 
Supplier recommended speaking to Elec Engineer to see if attachments and fuses exist to safely extract 16amp from household socket.

RCD 13 Amp Plug - 16 Amp Coupler. Order Code RCD1316GRP


Price: £39.14 (Excluding VAT at 17.5%)

< name="Q_903" value="1" ="">

* UK Construction Site Approved
* As used in UK hire industry




* RCD 13 Amp Plug - 16 Amp Coupler
* Test & Reset Buttons
* 30ma Trip typical
* 30 ms Trip speed
* Fibreglass case
* 2M Cable & fitted 13amp plug
* Max load 3840 watts

Online Catalogue |  Power Distribution 240V





Edited by levyte357 - 09 July 2007 at 10:24am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote JD01 Quote  Post ReplyReply Direct Link To This Post Posted: 09 July 2007 at 4:38pm
If you put something in a 13A outlet, it doesn't matter what current it is ABLE to draw, you will trip the line fuse at 13A. This box is merely an adapter from 13A household plug to blue CEE. Where should the additional 3A come from?
 
Amps have capacitors in a good amount. That's what enables a 2x4kW at 2 ohms amp to run from a european 1&a household outlet whithout ripping the line fuse. The average current draw from the mains stays below that as long as the crest factor in the music stays low enough (which will be the case in 95% of music styles). Most modern amps CAN'T even draw more than 16A (even the big LAB FP13000 rated with 2x6500W at 2 ohms isn't allowed to do that.... which is very questionable!).
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gingerbiscuit69 Quote  Post ReplyReply Direct Link To This Post Posted: 10 July 2007 at 11:30am
on my audiohead ah4000 (supposively 4k rms), plug got crushed in the back of the van, so changed it for a 16amp ceeform, but i thought id salvage the fuse out the plug before chucking it, was a 25amp rated fuse - being extremely illegal and im surprised no1 has been caught out already - if that amp goes awole, say the chassis goes live, thats 25amps pottentially going into someone killing nearly instantly!!

i have a 13-16amp converter (13amp plug and 16amp socket) for smaller stuff. generally a venue without 16+amp sockets, doesnt need systems which draw that much.

chatting to adam, he said at that dub thing in bristol this weekend, king tubbys took all their equipment off one 13amp socket, standard plug, phat cable ... must have been a 6mm copper rod in place of the fuse!! bit naughty.

tbh, if your having to ask about this subject, you should be keeping things simple, spread out the load over 13amp sockets, and leave bigger rated stuff until you are competent enough to handle it.

Edited by gingerbiscuit69 - 10 July 2007 at 11:32am
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ceharden View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ceharden Quote  Post ReplyReply Direct Link To This Post Posted: 10 July 2007 at 11:52am
We all know that the tricks regarding the fuses in 13A plugs happen.  I know someone who has a 13A-32A jumper with a bit of 40A fuse wire soldered instead of the fuse.  I'm surprised no-one has mentioned the widow maker yet..... (32A socket with two 13A plugs wired onto it!)

BUT!  None of these practises are to be recommended however because if something goes wrong (and it's more likely to) they could cause serious electrocution or fire.  DON'T DO IT!

The problem is that the British 13A plug is both over-engineered and sh1t at the same time.  I've seen them overheat, start arcing etc at currents less than 13A.  The weak points are the fuseholder and the actual contacts between the plug and the socket which can get loose and not make a good tight contact.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote josh Quote  Post ReplyReply Direct Link To This Post Posted: 10 July 2007 at 6:45pm
the thing is i find is disros are hard to find....can anyone point me to any websites?

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levyte357 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote levyte357 Quote  Post ReplyReply Direct Link To This Post Posted: 10 July 2007 at 9:08pm
Originally posted by gingerbiscuit69 gingerbiscuit69 wrote:


tbh, if your having to ask about this subject, you should be keeping things simple, spread out the load over 13amp sockets, and leave bigger rated stuff until you are competent enough to handle it.


tbh, I did'nt have to ask, as I know how I deal with this,  (without issue), and wanted to know what other people do.

The initial question was "what's the point of"  plugging huge (5k+) amps into household sockets when it won't be able to pull enough juice for full output @ 4 ohm bridge/2 ohm stereo. And what do some of the "pro's" here do.

There are a few amps out there that state in their specs, power consumptions of  240V/20+ amps at full power into 4 ohm bridge / 2 ohms per channel. And there are some "oldy but goody" that will draw 16amp well before full power.

Lot's of people who "say" they are competent, still use potentially lethal practises to  draw enough current from one socket to blow/trip the ring mains.

EDITED.


Edited by levyte357 - 10 July 2007 at 9:34pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote toastyghost Quote  Post ReplyReply Direct Link To This Post Posted: 11 July 2007 at 12:53am
There are always going to be venues that you arrive at to find they only have standard 13 amp sockets, rather than a ceeform though. In those situations, where there's a few hours to go til first tune and rig's in the van and you have to make do.

My previous 'advice' was prepended with a disclaimer for a reason, it is very very dodgy and I'd try and avoid it in every case.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ceharden Quote  Post ReplyReply Direct Link To This Post Posted: 11 July 2007 at 1:11am
The maximum current on amplifier specs is for continuous output.  Unless you intend to run a 0dB sine wave through your system all night that is not what the amp is going to draw.  Fuses such as the 13A ones in mains plugs are very slow acting.  You have to draw more than 13A for a fair while before they blow.

A large hire company I freelance for has 13A plugs on all of their amps, mainly Lab Gruppen fP6400 and Camco Vortex6 (ie 6kW amplifiers flat out).  Even running the systems very hard for long periods we never blow the 13A fuses on the amplifiers.  Why? Because the long term average current (what the fuse cares about) stays below 13A.

Maybe like the thread on amp rack current draw drag racing we could get people to experiment and find out how big a rig you can run off a 13A socket before the fuse blows!

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Post Options Post Options   Thanks (0) Thanks(0)   Quote JD01 Quote  Post ReplyReply Direct Link To This Post Posted: 11 July 2007 at 1:32am
You can't blow 13A fuses with the Lab Gruppen fP series or the Camco Vortex series. They are limited to 13A from the mains. That means IF they WOULD need more than 13A from the mains, the output will be decreased. With the fP6400 this happens sometimes at 2 ohms loads in bass range. With the FP10000Q or FP13000 this happens very often. And it's what makes the Camco Vortex that weak (they don't have big capacitors inside to catch peaks 'from within').
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ceharden View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ceharden Quote  Post ReplyReply Direct Link To This Post Posted: 11 July 2007 at 2:14am
Interesting. I'm sure I've managed to get a Vortex6 to draw more than that on bass peaks into 2 Ohms, especially if the mains voltage sags.

Must admit it wasn't exactly an accurate measurement tho...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote JD01 Quote  Post ReplyReply Direct Link To This Post Posted: 11 July 2007 at 3:10am
No, definitaly not when the voltage sags, because the SMPSU in the Vortex is unregulated (whereas the LABs are regulated). This means there isn't the 'lower voltage --> more current' behaviour. It acts like a conventional amp, when the mains sag, only that the mains sag earlier because of the low capacity of the buffer capacitors.
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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 11:32am
One thing is for sure. You UK people have some WEIRD and FUBAR weiring.
-
In norway we have 230v, floating earth (not supplied bye powerlines, found localy bye connecting copper to earth). On a standard home socket you can get 10-16 or even 20A. Fuses are not in the pluggs but in the equipment.

So UK guys!. Get with the program. Start driving on the right side and change your "stupid" sockets ;)

-

Or we can just all convert to Powercon...
�*�o�O�o�*�*: HansA, The FUBAR sound technician :*�*�o�O�o�*�
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