Hi Everyone,
So for a variety of bad reasons I took my Luxman 507ux integrated amp apart. Mainly to examine up close the IEC inlet and see about replacing it. Anyway, that issue aside, it seems the amp fuses the wrong side of the AC line?
Here's the inlet as you'd see from the back of the amplifier. I'd expect the left pin to be the line, and therefore it would eventually be the fuse wire right? Please ignore the missing fuse holder except to orient yourself. The PCB the inlet is mounted on seems to be for multiple models and/or countries. The actual fuses are further down.
The issue is the wires at the bottom of the inlet, shown below:
Underneath the inlet tabs, from left to right the wire labels read BLK and WHT. This appears to be reverse of what I would expect at least in the US. Line should be black, but it's on the right.
OK, so maybe this is just bad color coding?
However if we trace the BLK wire back to the power supply control board the BLK wire IS fused, but the WHT wire is not. In the large PCB in the middle you'll find a black transformer on the right side, the wires from the inlet terminate here:
Measuring from the wiring or the pins (as seen above) it is the BLK wire which goes straight to the fuse. You can also see the copper traces underneath.
So am I completely incorrect or does this seem like a manufacturing error in the US?
So for a variety of bad reasons I took my Luxman 507ux integrated amp apart. Mainly to examine up close the IEC inlet and see about replacing it. Anyway, that issue aside, it seems the amp fuses the wrong side of the AC line?
Here's the inlet as you'd see from the back of the amplifier. I'd expect the left pin to be the line, and therefore it would eventually be the fuse wire right? Please ignore the missing fuse holder except to orient yourself. The PCB the inlet is mounted on seems to be for multiple models and/or countries. The actual fuses are further down.
The issue is the wires at the bottom of the inlet, shown below:
Underneath the inlet tabs, from left to right the wire labels read BLK and WHT. This appears to be reverse of what I would expect at least in the US. Line should be black, but it's on the right.
OK, so maybe this is just bad color coding?
However if we trace the BLK wire back to the power supply control board the BLK wire IS fused, but the WHT wire is not. In the large PCB in the middle you'll find a black transformer on the right side, the wires from the inlet terminate here:
Measuring from the wiring or the pins (as seen above) it is the BLK wire which goes straight to the fuse. You can also see the copper traces underneath.
So am I completely incorrect or does this seem like a manufacturing error in the US?
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The fuse on the inletboard is clearly not used, as there are no (on the 'white wire') fused outlets available.
The amp is properly fused on the black wire on the psc board.
The amp is properly fused on the black wire on the psc board.
Please, this is dangerous voltage!
How much do you know about electronis, compared to any developer at Luxman's? Please don't fix a valuable amp that is not broken.
The white/ black or any color/live wire coding ends at the wall outlet. Inside an amp they can be reversed without any problem. There is no problem but you opening it.
How much do you know about electronis, compared to any developer at Luxman's? Please don't fix a valuable amp that is not broken.
The white/ black or any color/live wire coding ends at the wall outlet. Inside an amp they can be reversed without any problem. There is no problem but you opening it.
Some Luxman power cord for Japan market without polarity, both pin are same width.
@eriksquires, Please check the power cord that come with your amp polarized?
Perhaps Luxman overlooked the polarity of US mains, I think you can ask Luxman technical dept. to clarify.
@eriksquires, Please check the power cord that come with your amp polarized?
Perhaps Luxman overlooked the polarity of US mains, I think you can ask Luxman technical dept. to clarify.
Like Turbowatch2 already mentioned, live and neutral can be swapped in many countries. In the Netherlands, Germany and most of the European mainland, there are only mains plugs that can be put into the wall sockets two ways. Equipment meant to be sold all over the world will therefore have to be constructed such that it is safe no matter whether live and neutral are swapped.
Neutral is never considered "safe" - you always treat it as able to be as dangerous as live. Having said that, if you can place a fuse on the 'live' side, you do. Where mains plugs are not reversible, outlets can be switched on the live side (UK system is great in this regard).
There are various faults that can make neutral live in a building, such as a broken connection to neutral in a shared circuit - some device can then pulls the neutral up to live potential for all the others. This is why you always isolate (disconnect both live and neutral) before working on mains.
Back to the original piece of equipment - surprizing there's no protective earth - that's certainly not legal in the UK as the unit is metal.
There are various faults that can make neutral live in a building, such as a broken connection to neutral in a shared circuit - some device can then pulls the neutral up to live potential for all the others. This is why you always isolate (disconnect both live and neutral) before working on mains.
Back to the original piece of equipment - surprizing there's no protective earth - that's certainly not legal in the UK as the unit is metal.
Don't they have double insulated (class 2) equipment in the UK?
Over here, it is perfectly legal not to have protective earth on equipment in a metal case, but the insulation requirements are more stringent than with protective earth. I thought that was pretty international.
Over here, it is perfectly legal not to have protective earth on equipment in a metal case, but the insulation requirements are more stringent than with protective earth. I thought that was pretty international.
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The Luxman L-507uX is a Class II device.
Since OP is working on it, why not fuse the Live instead of Neutral to make it even safer?😉
BTW, the L-507uX MARK II is Class II equipment with functional grounding, not sure what difference internally.
Since OP is working on it, why not fuse the Live instead of Neutral to make it even safer?😉
BTW, the L-507uX MARK II is Class II equipment with functional grounding, not sure what difference internally.
Yes, we have IEC class II in the UK. It is often associated with plastic power tools etc, but arguably the class doesn't preclude a metal outer case provided it is 'double insulated' internally.
There is also occasionally older non-grounded stuff still around which isn't double-insulated either, and that is considered dangerous by modern standards (and some people don't realise the difference, unfortunately). Or modern imports that claim to be manufactured to class II (and other) safety standards, but aren't at all.
For me there should be a reason for not using class I, but presumably they had one.
There is also occasionally older non-grounded stuff still around which isn't double-insulated either, and that is considered dangerous by modern standards (and some people don't realise the difference, unfortunately). Or modern imports that claim to be manufactured to class II (and other) safety standards, but aren't at all.
For me there should be a reason for not using class I, but presumably they had one.
Double insulated in UK can have metal cases.....my UK spec/bought Denon system is all metal cases & double insulated. Basically "if" any component on the boards fails & goes "live" it will not make the case live. Also there is no way a person can push their finger through the vent grills to touch any "live" component.
To the OP...you can have a Live & Neutral only 2 pin plug with no "direction".....Most Hi-fi boards don't receive the mains AC voltage as they step down/transform it to 12V DC for the PCB boards....so the mains wiring live/neutral is only to the internal transformer...& most transformers don't mind which is live/neutral..as otherwise all 2pin plugs for this situation would be directional...
This discussion shows very colorfull why some see DIYS so critical. Such threads give the impression of people without specific education and no desire to read and learn before acting, carelessly messing around with something dangerous. Here leathal electricity. It is just the same with car or home repairs, guns, any technical thing in our world, having relationshops, pet's or children . If enough people mess up, some state lesgislature will see the need for more regulation, laws and all the paternalism free inteligent people hate. If you do something, you have to do it responsible, not in a know-it-all manner. If this does not work, sooner or later some police man is going to slap you on your fingers.
Some reading would have made this whole confusing thread obsolete.
Some reading would have made this whole confusing thread obsolete.
Well, the thread has wandered, but to answer the OP's question, yes I do believe it is an error by the manufacturer. Whether it was never caught or was caught and a decision made that revision was not necessary is a different issue.
The amp is perfectly complying with electrical rules. There is nothing more to say about this. You can construct it differently, but there is noting wrong with it.
By making it comply with bidirectional power outlets, it is automatically in agreement with unidirectional, too.
The people at Luxman are no idiots.
For example the "SCHUKO" power outlet in Germany is bidirectional, but still should have the live wire at the right side. You can expect it to be right, but always have to check. High power outlets here are made differently and operate different electical consumers.
The number of deadly accidents with this system in Germany is less than 50 people each year. Compare this to billions of electrical appliances and installations on the one and 84 millions of uneducated users on the other side! It is 99.99999% idiot proof.
Quite a save system. Most accidents are in bathrooms, where idiots use a hairdryer in the bathtub or a smartphone charger under the shower. The inflation in cheap Chinese chargers from Amazon, eBay and the like is the cause for rising numbers of accidents in the last years. Almost anyone I know has experienced some charger smoking, burning or exploding. There was a clear warning fine printed on any of it: "Made in China". Any company like Luxman would have been out of bussines for building and selling such products... the Lux amp is OK.
By making it comply with bidirectional power outlets, it is automatically in agreement with unidirectional, too.
The people at Luxman are no idiots.
For example the "SCHUKO" power outlet in Germany is bidirectional, but still should have the live wire at the right side. You can expect it to be right, but always have to check. High power outlets here are made differently and operate different electical consumers.
The number of deadly accidents with this system in Germany is less than 50 people each year. Compare this to billions of electrical appliances and installations on the one and 84 millions of uneducated users on the other side! It is 99.99999% idiot proof.
Quite a save system. Most accidents are in bathrooms, where idiots use a hairdryer in the bathtub or a smartphone charger under the shower. The inflation in cheap Chinese chargers from Amazon, eBay and the like is the cause for rising numbers of accidents in the last years. Almost anyone I know has experienced some charger smoking, burning or exploding. There was a clear warning fine printed on any of it: "Made in China". Any company like Luxman would have been out of bussines for building and selling such products... the Lux amp is OK.
Almost everything is made in China nowadays. If you don't want to use equipment made in China, you can practically only use vintage equipment and DIY equipment.
I don't know this discussion has anything to do with cheap Chinese chargers that "Made in China", Do you meant because this integrated amp is not "Made in China" it must be OK?
No, it was only mentioned to show where people get killed with electronics today. Not with this perfectly correct principle that is realised in the Lux amp and used for ages..
In Germany the analysis of fatal electric accidents showed that because of these chargers the death toll, after years of sinking, is now rising. We have a single type of object that is of statistic relevance. Coincidentally a minimum 99.9% of these objects comme from a country known to forge any safety sign ever invented and ignore international rules as a general principle of generating profit. Japan on the other side does apply to safety regulations.
Even when this is a statistic of about 50 fatal cases compared to 84 million users, this may show that these stupid western safety concerns are somehow not so stupid at all and ignoring them is in fact, not only theoretically, deadly.
There have been no cases reported of Japanese Luxman amps killing people in Germany, which is the start of this thread. A wide part of Europe uses this grounding scheme that some wrongfully declared to be incorrect. There is nothing wrong with this amps safety.
In Germany the analysis of fatal electric accidents showed that because of these chargers the death toll, after years of sinking, is now rising. We have a single type of object that is of statistic relevance. Coincidentally a minimum 99.9% of these objects comme from a country known to forge any safety sign ever invented and ignore international rules as a general principle of generating profit. Japan on the other side does apply to safety regulations.
Even when this is a statistic of about 50 fatal cases compared to 84 million users, this may show that these stupid western safety concerns are somehow not so stupid at all and ignoring them is in fact, not only theoretically, deadly.
There have been no cases reported of Japanese Luxman amps killing people in Germany, which is the start of this thread. A wide part of Europe uses this grounding scheme that some wrongfully declared to be incorrect. There is nothing wrong with this amps safety.
Well, there's no point in my replying to since you are spamming the thread, except that I want to reassure the OP that he is indeed correct. It is obviously an error the manufacturer did not intend, and whether it is adequately safe is a completely different issue, no matter how many words and rants Turbowatch2 throws in the thread.
"Could as well be connected the other way round" is not a mistake of an manufacturer. It is one of two correct ways.
Maybe just read the technical description of this safety principle?
Wrongly insisting on something that is OK to be wrong, provoces simple minds into fixing something not broken. With an unknown, but obviously dangerous outcome.
Maybe just read the technical description of this safety principle?
Wrongly insisting on something that is OK to be wrong, provoces simple minds into fixing something not broken. With an unknown, but obviously dangerous outcome.
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