Hi all,
small topics, but never know
I noticed UK plugs include a fuse, my 250 DR came with Naim Lite mains cable and there is the simbol of a fuse on the plug.
EU plugs don’t have any fuse:
what is the scope of the fuse in the plug?
prevention of damages from electricity variations, lightings etc?
might be worth introducing a fuse in the mains distributor or do Naim Electronics have other fuses inside in order to protect them?
thanks
Guido
That’s just how we do it in the UK. All mains plugs contain fuses.
All Naim components have fuses inside as well. Look at the iec socket on the back.
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thanks Robert, so you don’t think I should add another fuse before the component, or do you think it might be beneficial?
The fuse in the plug is there to protect the cable from plug to appliance. Similarly the fuse in the consumer unit is there to protect the cable from consumer unit to socket
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thanks, so the appliance is fully protected by its fuse
The appliance is protected by the fuse inside it near the power socket.
The fuse in a UK power plug is there to protect the flex that links it to the appliance only. The reason for this is that UK domestic wiring uses ring mains that can include quite a large number of outlets, and therefore require a high rated circuit breaker (or fuse in older installations) which it too high to safely protect the individual flex. Thus the additional fuse protection is required.
Other countries generally have different domestic wiring arrangements which do not require these extra fuses, so you won’t see them in US, European and other plugs.
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I read naim assumed the fuse in the UK wall connector is decremental to the performance but that the UK naim design plug is likely beneficial to the EU Schuko made by Furutech so it evens out. I have not compared but Furutech schuko is not a bad one and having less fuses in the power path is likely better.
Is it really worth worrying about for the sake of a relatively minor potential improvement?
The products have been designed by Naim to work in the UK this way and are well protected.
Easy to get a Hi-Fi hard-on about fine tuning (been there myself) but it’s not really gonna make much (if any) long term difference to the enjoyment of your music. And if you’re not already enjoying the music first and foremost then there will be something more fundamentally wrong that removing a fuse will not fix.
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My question was the opposite as I live in Europe where plugs don’t have fuse: as in UK there is a fuse, is it worth adding it ?
You should have received a mains cable suitable for your country. If you received a Naim lite cable as I understand it these are UK 3 pin plug and cannot be used outside of the UK.
Final answer; don’t modify any mains plugs by adding or removing fuses.
I’d even go as far to suggest this discussion is in breach of the forum rules;
Quote
An extension of this is discussion of alterations to the mains wiring, sockets, plugs, fuses and mains leads.
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Thanks. I clearly need to learn how to read English.
You must use a mains lead compliant to the electrical regulations applicable to your country, with no deviations, additions or modifications.
Naim only use fused plugs because it is a safety requirement in the UK. I’m sure they would omit the fuse it it was possible to do so without compromising safety, but it isn’t.
While a non fused plug is preferrential, it’s not legal in the UK. So really the discussion about whether a non fused Furutech plug is better than a fused Naim air plug is irrelevant: everyone uses the only type of mains cable they can - there is no choice in the matter. At least not one that adheres to local regulations.
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I’m confused. Isn’t the mains fuse inside the 13 amp plug in a typical UK wiring system?
Or is there one in the fuse in the Naim ‘black box’ and one in the 13 amp plug?
Very befuddled - I am no electrician!
The fuse in the 13A plug protects the cable & IEC plug and is part of and unique to the UK Ring Main system. This can have selection of amp ratings from 3 to 13.
The fuse in the Naim unit is to protect the Naim. These are very specific to the actual Naim model, they are slow blow and rated for the Naim model, as an e.g. 2.15
I understood the electrical system and legislation in UK is different, I should not evaluate to put any fuse in the mains distributor as there is already a fuse into the naim electronics to protect the naim electronics. It’s strange to find these little differences.
Here’s another example: in EU there is sometimes a discussion about the live - neutral position of the plug. All components sound correctly with the live on the right and the neutral on the left, but some electronics are made in a different way and the whole system will not sound right, this in EU can be solved simply turning the plug. In UK and US this is not possible as UK and US plugs have a unique direction of usage. But this does not seem to be a topic for discussion in US and UK
I would not say the difference between UK & EU wiring is little, they are completly different.
UK is a ‘Ring’ power socket sysem, EU is ‘Radial’
The UK Ring is a circuit connected at both ends to the same point (a therortical ‘ring’) It has numbers of outlet sockets on the ring & is protected as a whole circuit by a 32 amp RCCB (fuse).
The socket plugs are each fitted with a fuse typicaly between 3 to 13 amps to protect the individual cable & component connected to that plug.
The EU Radial are multple branches or ‘radials’ that supply one or more outlet sockets & are typically proected by a 16 amp RCCB/Fuse
The socket plugs and the individual cable & component connect to that socket are procted by the 16 amp RCCB/Fuse.
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this is very interesting, had not idea about it, thanks
UK seems more similar to the stellar approach that is used inside the good mains distributors
I’d not say that. The ring main means it is difficult to predict with certainty that both sides will be balanced and since there could be a large current inbalance, a fuse is needed to cope with that potential uncertainty.
I’d call it a design flaw personally. I’m sure it seemed like a good idea at the time but overall the radial is the more popular. Worth noting, even in the UK the ring main isn’t the only method. Radials sre also common.
As for polarity, for un earthed hifi in both the US and Japan, neutral is on the left and if the polarity matters, the unit is often supplied with a power chord with a small bump on one side of the plug so you can feel which side goes left even if the socket is hard to see directly.
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