Mains specs are frying my brain

G a f f e r

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I thought this was easy but the more I look into it the more complicated it becomes.

Being part of the Eu means we "harmonised" mains voltages and new standards were set:
EU = 230V -10% +6% (i.e. 207V - 243.8V)
UK = 230V -6% +10% (i.e. 216.2V - 253V)
Both at 50Hz +/-1%

However, nothing actually changed. Physically, we were still on the old 240V (+/-10%) and the EU were still on the old 220V (+/-10%)

So the "harmonisation" was just a way to make things match "on paper", physically the same supply transformers were still being used in the UK for 216V-264V and in the EU for 198V-242V

So on to my question, I know voltages vary over the day and depending on who's using what on your street/grid etc etc, but testing my mains voltage I'm pretty much at 245V in my house.
This is within both "old" and "harmonised" UK spec, but is outside both "old" EU and "harmonised" EU spec.
I have my eye on a second hand hifi component from the 1990's rated as 220V. It has a green label on the back. The manufacturer also made the same product for the US (red label saying 110V) and the UK (blue label shown as 230/240V). That means the manufacturer themselves made a distinction between EU models and UK models.
If I buy the EU model rated at 220V, will I have an issue on my 245V (but sometimes possibly up to 253V) mains supply?

Should I buy a buck transformer to step it down our UK 240V mains supply to 220V or is that me overthinking things?




(P.S. by my calculations post-brexit duty/vat/handling charges means it'll cost about 1/3 more than buying from the UK which puts me off a bit but thought I'd ask in case I do go for it).
 
I don't know if the voltage difference would make a difference.

However, I don't understand why you would pay a third more for a product imported from the US if its available in the UK? Also, if you do need a step down line transformer, you're probably looking at an additional £200-300.

I'd get a UK spec model of whatever it is!
 
Never thought about this but interesting. Can't comment technically but I've kit from 1975 to 2021 and a quick grovel round the back of some of my 1990s stuff reveals labels of 220-240v on Technics and Panasonic decks and DVD recorder, and 220v on Micromega (French) CD player which is in regular use and works fine. Just measured my voltage at 235.
 
The transformer may have tapping for 220V and 240V AC. If so it maybe possible to change it from 220V to 240V. It's is not advisable to run linear power supply transformer equipped equipment on the incorrect voltage.

Switch mode power supplies, SMPS on the other hand can usually run on 90V to 260V AC or 200 to 260V AC wthiout any changes.

 
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I don't know if the voltage difference would make a difference.

However, I don't understand why you would pay a third more for a product imported from the US if its available in the UK? Also, if you do need a step down line transformer, you're probably looking at an additional £200-300.

I'd get a UK spec model of whatever it is!

I'm not importing form the US, I'm importing from the EU (hence why I'm asking about using EU products in the UK based on slightly different voltages and specs between the EU and the UK).
Some people who've already done this have suggested adding a buck transformer to step our 240V down to 220V which is why I was considering it.

If it's any help I'm looking to get a higher end Tuner to replace my vintage one (technics ST3500)....things like Quad 66, Magnum Dynalab FT101, Meridian 504, Naim NAT 05 etc etc are what I'm looking for, but can't find any UK ones on sale here at a decent price whereas there are some available from Holland via eBay right now.

If I did get the EU version I could also ask the manufacturer to modify it (over to UK spec) but that would also be extra cost.


You do need to pay duty (2.5%) and VAT (20%) as well as Royal Mails exorbitant "handling fee" of £12 and even with the seller reducing marked value to only €80, that's still about £55 more than a UK one......

Ignoring my specific item search though, this goes for anything you're tempted to buy from the EU really, will it be OK with our higher voltage? :)
 
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If it's any help I'm looking to get a higher end Tuner to replace my vintage one (technics ST3500)....things like Quad 66, Magnum Dynalab FT101, Meridian 504, Naim NAT 05 etc etc are what I'm looking for, but can't find any UK ones on sale here at a decent price whereas there are some available from Holland via eBay right now.

I think you maybe disappointed!
 
Ignoring my specific item search though, this goes for anything you're tempted to buy from the EU really, will it be OK with our higher voltage? :)

Already answered in post#4.
 
I think you maybe disappointed!
Really, is it that bad? I thought they were great tuners (hence on my shortlist).
There is a Magnum Dynalab for sale here in the UK but it's a US model so back at same issue really.
The hifi shop in holland is selling a Meridian 504 and I just missed a UK version by about 24hrs so that's what I was looking at.

Already answered in post#4.
OK so you would suggest either step down from 240V to 220V with an external box or send it to manufacturer to get them to correctly modify it internally?

I've a feeling that would add about £100 to the cost :( so it looks like I'll just have to be patient (looking at ebay something will appear there at a rate of about 1-2x a month :smashin:).
 
Really, is it that bad? I thought they were great tuners (hence on my shortlist).
There is a Magnum Dynalab for sale here in the UK but it's a US model so back at same issue really.
The hifi shop in holland is selling a Meridian 504 and I just missed a UK version by about 24hrs so that's what I was looking at.


OK so you would suggest either step down from 240V to 220V with an external box or send it to manufacturer to get them to correctly modify it internally?

I've a feeling that would add about £100 to the cost :( so it looks like I'll just have to be patient (looking at ebay something will appear there at a rate of about 1-2x a month :smashin:).

The Quad 66 is a pre-amp.

The US radio system uses different de-emphasis and channel spacing so a US version would require a lot more mortifications than just the PSU.

I have owned a Quad FM4 since new in the nineties. It was my first stand alone tuner and will be my only ever FM hi-fi tuner purchase. Streaming is the way to go now.

Why guess costs, ask. If you can find a local TV / electronics repair service or shop, I would expect it to be a lot less, but they can confirm.
 
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That's one of the 66 range - there's also a tuner and a CD player

My bad, thought the range had different model numbers like the power amp 606.
 
Not sure you not over thinking things. Eu product will work in the EU and we where part of the Eu until very recently. All good to go, we’ll you have the plug to swap out.
 
There's really no problem with mains varying by 10-15% with equipment with regulated power supplies, so things like tuners and pre-amps will suffer no ill effects from 220V or 240V. I built and designed high speed cassette copiers for a few years and we used the same transformer and power supply configuration for 220V and 240V countries. If you think about it, a 15% increase in line voltage will be replicated on the other side of the transformer, so this will increase the unregulated voltage from say, 15V to about 17V. The regulator will be able to handle over voltage of 24V or so, and will not need to work any harder for the extra couple of volts.

Where it can matter is with power amplifiers, as the supply is less likely to be regulated, so the voltage supplied - up to 70V per rail in high power amplifiers can change by 15-20V. This can have an effect on the ultimate power output and peak voltage, as well as more subtle changes around the crossover between Class A and AB.

This only applies to analogue (linear) power supplies as opposed to switched mode power supplies, which have much more closely regulated voltage rails and can be used for power amplifiers as well as preamps and tuners etc.

If you import older equipment from the US, as well as the voltage, the frequency change can sometimes cause problems with mains driven cooling fans, as the reduction in frequency significantly reduces the amount of air they can move. These days everything has low voltage DC fans, but you can still find older amplifiers with mains fans.
 
Not sure you not over thinking things. Eu product will work in the EU and we where part of the Eu until very recently. All good to go, we’ll you have the plug to swap out.

Yes, because most equipment has SMPS PSU's to cater for world wide markets, with other specific items being localised to suit.

Linear PSU's are different.
 
Yes, because most equipment has SMPS PSU's to cater for world wide markets, with other specific items being localised to suit.

Linear PSU's are different.
Not really, after the transformer their be voltage regulators to manage the dc voltage on anything worth using.
 
Not really, after the transformer their be voltage regulators to manage the dc voltage on anything worth using.

It not what is after, it's what is before i.e.at the mains input, the transformer.
 
That difference is very unlikely to saturate your transformer.

You’d need to be drawing a whopping current for anything to be an issue, and that’s only if the transformer hasn’t been built with enough leeway.

I’m surprised you want to buy something so old though. If you get unlucky it’s just another electronic box that’s too expensive to be worth a repair.

This may interest you.


Ps, I’m pretty sure the likes of Naim use the same transformer for Europe and the UK anyway.

Could be wrong though.
 
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Really, is it that bad? I thought they were great tuners (hence on my shortlist).
There is a Magnum Dynalab for sale here in the UK but it's a US model so back at same issue really.
The hifi shop in holland is selling a Meridian 504 and I just missed a UK version by about 24hrs so that's what I was looking at.


OK so you would suggest either step down from 240V to 220V with an external box or send it to manufacturer to get them to correctly modify it internally?

I've a feeling that would add about £100 to the cost :( so it looks like I'll just have to be patient (looking at ebay something will appear there at a rate of about 1-2x a month :smashin:).
I would not be too worried about the voltage difference with a tuner. Certainly not worth an extra £100 on step down devices.
Tuners will have an internal regulator. It might get a bit hotter, if the difference is a lot but a well designed unit should be able to cope.
 
So basically more of an issue with power amps or valves, less of an issue with SS devices like tuners? Great news if so as I may wish to buy other kit form the EU in the future and this will set my mind at rest.
I have fired off an e-mail to Meridian themselves and will see what they suggest as well (will update this thread with their reply).









EDIT: didn't want to necrobump this thread but I promised an update so here it is 1 month later....

Here is the e-mail I sent to meridian on their online form


Hello.
I am interested in buying a used Meridian 504 Tuner here in the UK (replacement for my vintage Technics ST-3500). I have seen some for sale in the EU, where the rear is labelled "220V" with a green label. This is distinct from your UK models which either have "240V" or "230/240V" in a blue label on the rear.
My mains voltage at home is usually sitting at about 245V and I would've thought an EU 220V model would've been fine to simply plug in here, but seeing as you yourselves make the distinction on your kit, would there be any issue with this (getting a UK plug and plugging an EU model directly in)?
If there is an issue, would you offer a service to "convert" an EU model over to UK spec?
Thank you for any help.

To which I received no reply. Zero. Nada. Zilch. So Meridian Customer Care scores 0/10 :smashin:

I have since managed to secure a UK 504 in excellent condition so the above no longer applies to my tuner purchase but is useful nonetheless if I ever consider getting anything else from the EU in the future.
 
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Just for information IEC 6038:2009 - IEC Standard Voltages states the nominal voltage for 50 Hz supplies to be 230 V +/-10% and 120 V for 60 Hz systems +/-10%. So 2009 is when EU and UK voltages should have aligned from.
 
Hi just clarifying the topic.
1. A switch mode power supply rarely cares what the voltage is and there are plenty which will run from 100v (Japanese), 120V (USA) 220(EU) and 240(UK). Whereas Sat boxes , DAB and FM tuners and DTV tuners , DVD and CD players usually use SMPSUs, ,only Home cinema and a few amplifiers do.
2. A linear power supply is somewhat more fussy . If the voltage is excessive ,it puts pressure on the capacitors and could lead to premature failure. If the voltage is low , it will not produce its rated power and might have" motorboating" ..a putt put sound However in consumer electronics , whether the voltage is 220 or 240 makes very little difference.
3. Many amplifiers have a button or selector for 4 or 8 ohm speakers . If the selector is put in the 4 ohm setting,then the voltage from the power supply is reduced a little . So running any EU Amplifier in the UK on the 4 ohm setting, will automatically compensate for the higher voltage. Not necessary but more belt and braces.
4. Some classical amplifiers have a tapped mains transformer so that they can be adjusted to local conditions .. more prevalent with Valve models ..so ideally these should be adjusted.
5. It is generally a bad idea to use USA designed product in Europe ,if it has a linear power supply. Yes the voltage is a pain, but the problem is a bit deeper than that. A simple autotransformer can be used to sort the voltage , ..The Transforner is designed to run at 60 hz not 50hz and contains less Iron and copper. They run much hotter and will not withstand overvoltages
 

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