Electricity Supply and 230V devices --> Problem?

[Stedes]

Hi guys

 

Was just reading a classified ad which a fellow member mentioned that as the supply in Australia is 240V, devices that are 230V especially valve gear breaks!

 

As I own and operate a number of hifi equipment rated at 230V I decided to do a little bit of research and I ended up with a bit of a headache. My understanding is that based on Australian standard AS 60038, the nominal supply of Australia was changed to 230V from 240V some years ago with 230V now being the standard. I also understand that the acceptable operating range based on this standard is +10% -6% which means 217V - 253V.

 

I don't understand why 230V devices would "break". Even if 240V was the nominal standard then the range would be 226V to 264V so one would think a well designed 230V supply could cope with that.

 

Is the problem that the standard isn't followed and what we're getting from the grid is actually higher? If anyone with experience on the matter could shed some light I'd greatly appreciate it.

Edited April 15, 2015 by Stedes

[Bronal]

Your post raises a number of issues:

 

1 -  yes, the 'official' voltage in Australia is 230 (to align with Europe, the UK and other countries) but the reality is that the actual voltage you're getting may be up to 250V and beyond at times.  Here in the ACT my voltage is normally between 245 and 250.  I believe parts of WA are the worst culprits.  Why this is I don't know - someone else will have to explain.  You can buy a cheap device from Jaycar that plugs into a power point that will tell you exactly what you're getting.  Mine's reading 251.5V ATM.

 

2 -  your equipment appears to be SS, with the exception of your Audible Illusions preamp.  SS equipment is more tolerant of voltage fluctuations so is unlikely to be affected, as you have suggested, although poorly specced power transformers may become saturated and hum and rattle if subjected to 250V.  Also, Chinese, other Asian and some European equipment still has 220V transformers.

 

3 - valve equipment OTOH is less flexible as regards voltage range and excess voltage will result in decreased valve life or early failure. (I'm not a tech so someone will have to explain this as well).

 

I now have this rule of thumb:  I use a 240/220 stepdown for all Chinese equipment (even equipment that is supposedly 240V) and equipment from other countries that used to be on 220V (mainly Europe), after Patrick Turner demonstrated to me that the transformer on an AR amp I'd bought labelled '240V' was in fact a 220V transformer.  To avoid a proliferation of these devices I'm thinking of getting a large Tortech model and plugging my Isotech power strip into that.  I don't have any 110/115/117V equipment.

 

Happy to be corrected on anything I've said.

Edited April 15, 2015 by bronal

[Whites]

The fundamental issue with the rating is that equipment rated at 230v produced overseas doesn't necessarily have the higher tolerance as required in Australia.

[Guest Muon]

bronal summed it up pretty well I think.

 

I specifically went for a actual 240v PS in my original amp, and made sure the supply in my phono stage was 240v also (238v really)...both are tube.

 

Mains here in the unit are a steady 250v.

[Bronal]

The fundamental issue with the rating is that equipment rated at 230v produced overseas doesn't necessarily have the higher tolerance as required in Australia.

 It shouldn't need it if the voltage was around 230.

 

So we're back to the original question - why is voltage so high?

[Saxon Hall]

 It shouldn't need it if the voltage was around 230.

 

So we're back to the original question - why is voltage so high?

This has been discussed many times on this Forum and I believe that it is a very difficult subject to explain in any sort of meaningful way to the majority of people on here. This is not meant in a disrespectful manner , just acknowledging that it is a complex subject. There is quite a bit of information available online if you care to research it

Here is an example of a Technical Paper on the subject. Have a read of it and you will see what I mean by "Complex"

http://www.elec.uow.edu.au/apqrc/content/technotes/technote7.pdf

[Guest Muon]

The supply is a complex issue, but what we are dealing with is not related to those suppliers issues....we need to deal with what our gear runs off regardless of the issues that affect them.

 

Edit: the supply is what it is, on paper 230v, in reality not often 230v or even close to it.

Edited April 15, 2015 by ortofun

[Bronal]

This has been discussed many times on this Forum and I believe that it is a very difficult subject to explain in any sort of meaningful way to the majority of people on here. This is not meant in a disrespectful manner , just acknowledging that it is a complex subject. There is quite a bit of information available online if you care to research it

Here is an example of a Technical Paper on the subject. Have a read of it and you will see what I mean by "Complex"

http://www.elec.uow.edu.au/apqrc/content/technotes/technote7.pdf

That wasn't the question.. The question was: why can't the network deliver ~230V.  I acknowledge that there will always be fluctuations.

[Saxon Hall]

That wasn't the question.. The question was: why can't the network deliver ~230V.  I acknowledge that there will always be fluctuations.

Basically because it is impossible. That is why they only have to supply within a specified range. Not what you want to hear no doubt but if the equipment is properly designed it will tolerate voltage in this range. Of course we all know that a lot of equipment is illegally imported without ever being tested or sent for approval so al lot of it cannot tolerate even minor voltage fluctuations.

Here is another link which talks about the voltage range permissible in Australia. Which is 230volt +10% to -6% (253 V Max to 216V Min)

http://electricalconnection.com.au/article/10017796/when-voltage-varies

[Guest Muon]

OK, try a tube amp that has a 230v PT, and feed it 250v, that is within range? you will find the heater voltages above what they are spec'ed for. You will have heaters that should be getting 6.3v actually getting close to 7v.

 

This is with properly designed equipment.

[LogicprObe]

That wasn't the question.. The question was: why can't the network deliver ~230V.  I acknowledge that there will always be fluctuations.

 

The providers will tell you it's because of private solar feed in etc.................but in reality, it's better to deliver over than under and because most of the network was designed foe 240V even though we are now offically 230V.

[Equaliser]

Not all valve amps are affected only tube amps with unregulated heater and cathode supply will suffer the 10-12% increased voltage. This doesn't instantly break or kill your amp that is a commo misconception it will wear your tubes lifeapan thats for sure. Some very well engineered (not many) tube gear have current and voltage regulators to keep valve power suppy in spec no matter the input voltage on the mains. Anything above 250vac should and would trip the fuse in your hifi equipment as electrical equipment designed for 220v, 230v and 240vac regions are fitted with a universal standard 250v max fuse.

[Zaphod Beeblebrox]

Good valve amps, like Weston Acoustics products are specifically designed for Australian conditions. You can use them with absolute confidence. Same deal with any Australian built equipment, particularly those using Australian made power transformers.

[betty boop]

While designed for Australian spec....the problem can be out of spec supply....

The best thing can do is contact your electricity provider and let them know out of spec. They are duty bound to comply

[hochopeper]

That wasn't the question.. The question was: why can't the network deliver ~230V. I acknowledge that there will always be fluctuations.

End of the day 'why' is a financial issue. Reducing the voltage fluctuations costs money and people already find electricity supply too expensive. Fixing stuff that is out of current spec is legislative requirement so they will fix it. But, if we're to talk about changing the spec the question becomes how much will average consumer pay for this?

Edited April 15, 2015 by hochopeper

[Guest Muon]

Not all valve amps are affected only tube amps with unregulated heater and cathode supply will suffer the 10-12% increased voltage. This doesn't instantly break or kill your amp that is a commo misconception it will wear your tubes lifeapan thats for sure. Some very well engineered (not many) tube gear have current and voltage regulators to keep valve power suppy in spec no matter the input voltage on the mains. Anything above 250vac should and would trip the fuse in your hifi equipment as electrical equipment designed for 220v, 230v and 240vac regions are fitted with a universal standard 250v max fuse.

Of course, but those that don't have regulated are still correctly designed IMO.

 

Yup, shorter life span

 

Other voltages will also be slightly higher, so not running at the intended operating points....yeah, I could be seen as being picky by some

 

Good valve amps, like Weston Acoustics products are specifically designed for Australian conditions. You can use them with absolute confidence. Same deal with any Australian built equipment, particularly those using Australian made power transformers.

Yes, 240v PTs, not made to Australian spec', made for Australian conditions.

 

Oh, my PT is Chinese and is 240v

[davewantsmoore]

 230V +10% to -6%

 

Is the Australian standard.

[davewantsmoore]

correctly designed IMO

 

"Correctly" need to be defined as a measure.     If a heater (for example) voltage changes 'too much' when subject to 230V -6% +10%.   Then perhaps your definition of "correctly" is not congruent with Australian conditions?!?

[Guest Muon]

"Correctly" need to be defined as a measure.     If a heater (for example) voltage changes 'too much' when subject to 230V -6% +10%.   Then perhaps your definition of "correctly" is not congruent with Australian conditions?!?

I see it as more of a situation where the power supply is incorrect

[Guest Muon]

As long as folk are aware of the difference between official voltage (on paper) and actual real voltage here, It's cool

[Equaliser]

Of course, but those that don't have regulated are still correctly designed IMO.

 

Yup, shorter life span

 

Other voltages will also be slightly higher, so not running at the intended operating points....yeah, I could be seen as being picky by some

 

Yes, 240v PTs, not made to Australian spec', made for Australian conditions.

 

Oh, my PT is Chinese and is 240v

 

Well regulators are just overkill and only found in very expensive tube gear, although I have found some one man team manufacturers do it just for the sake of it. It doesn't really count as proper engineering but it's a good thing to have as is having regulated supplies in solid state equipment is always a good thing to keep power supply rails within specification. 

 

No matter where the transformer is made in, as long as it's winded to spec for the rated input voltage it is for, then it should not be a problem. Using 220v rated transformer in grey import gear is the users fault not the manufacturer. If the manufacturer states there amps are suitable for 230-240vac conditions but only supply 220vac transformers, then there's really two pointers to this. Either the manufacturer has stringently tested there transformers with the +/- 10-12% increased input voltage conditions and has said it's ok or the manufacturer hasn't tested it in said conditions and only have 220vac at hand (which ends up causing problems) then this is the manufacturers fault.

 

A power conditioner/power plant is one method of eliminating high mains if you have alot of gear and don't want to buy individual step down trafos from 240vac to 220vac. 

 

If you have diy / cheap tube amps from China you can calculate values for a voltage dropper to drop the voltage of the input side of trafo. Something like a 20watt 70ohm resistor between the mains and the switch should drop whatever input vac you're seeing to about 220v. This also eliminates high HT if it's spec'ed to be 250v b+ for a tube especially if the screen is connected directly to HT, the valves would be running lot less power and less heat output. Also reduces filament voltage, so it prolongs the tube lifespan according to it's rated datasheet values.

Edited April 16, 2015 by DefQon

[Zaphod Beeblebrox]

No matter where the transformer is made in, as long as it's winded to spec for the rated input voltage it is for, then it should not be a problem. Using 220v rated transformer in grey import gear is the users fault not the manufacturer. If the manufacturer states there amps are suitable for 230-240vac conditions but only supply 220vac transformers, then there's really two pointers to this. Either the manufacturer has stringently tested there transformers with the +/- 10-12% increased input voltage conditions and has said it's ok or the manufacturer hasn't tested it in said conditions and only have 220vac at hand (which ends up causing problems) then this is the manufacturers fault.

Sadly, in my business, I've seen more than my fair share of Chinese power transformers that are rated for 240 VAC, but saturate at Voltages as low 200 VAC! Many US power transformers overheat when operated on 50Hz mains frequency. European stuff seems to be generally OK, but for the very best transformers, I suggest that Australian made ones be used.

[Guest Muon]

@@Zaphod Beeblebrox

 

"I've seen more than my fair share of Chinese power transformers that are rated for 240 VAC, but saturate at Voltages as low 200 VAC"

 

Is this over the last two decades, or recent? Were they respected brands, or the cheapest of cheap fodder?

 

Edit: had! to be a typo in there.

Edited April 16, 2015 by ortofun

[Zaphod Beeblebrox]

@@Zaphod Beeblebrox

 

"I've seen more than my fair share of Chinese power transformers that are rated for 240 VAC, but saturate at Voltages as low 200 VAC"

 

Is this over the last two decades, or recent? Were they respected brands, or the cheapest of cheap fodder?

 

Edit: had! to be a typo in there.

As recently as last year and the cost of the item was substantial. I'm sure there are quite a few decent Chinese products (in fact, I've worked on quit a few), but, I'm afraid, assuming Chinese manufactured equipment to be similar to early Japanese equipment may be a fatal mistake. The Japanese have a general tendency to build the highest quality equipment, at any given price. IME, the Chinese appear to be driven to build products for the lowest possible price.

Again: For the BEST power transformers, choose Australian made. Always.

[Guest Muon]

As recently as last year and the cost of the item was substantial. I'm sure there are quite a few decent Chinese products (in fact, I've worked on quit a few), but, I'm afraid, assuming Chinese manufactured equipment to be similar to early Japanese equipment may be a fatal mistake. The Japanese have a general tendency to build the highest quality equipment, at any given price. IME, the Chinese appear to be driven to build products for the lowest possible price.

Again: For the BEST power transformers, choose Australian made. Always.

OK, thanks for that, ZB

 

Was just after the context of it, and it is a shame that it is still happening so research is a must if purchasing an overseas product. I guess I did OK then as the brand I got was considered as cheap but was properly made, even with 250v it gets only warm.

 

I do agree that going with Aussie made is often preferable, as long as the person is highly reputable like Earle is