Using a 3 prong without PE is eh.... Use a 2 prong version instead.
Some questions:
1. please explain the speaker ground being connected to PE and what would the negative side be if it is like that.
2. "better shielded" ? To what is the shield connected then?
3. what about the casing of Class 1 devices with now PE not being connected? Is Audio GND connected to the casing?
4. is electrical safety relevant in the area where you live as you state PE ultimately does not serve a purpose there?
5. are there legal consequences/liability to be expected when such a device is sold and things go wrong for some reason?
Some questions:
1. please explain the speaker ground being connected to PE and what would the negative side be if it is like that.
2. "better shielded" ? To what is the shield connected then?
3. what about the casing of Class 1 devices with now PE not being connected? Is Audio GND connected to the casing?
4. is electrical safety relevant in the area where you live as you state PE ultimately does not serve a purpose there?
5. are there legal consequences/liability to be expected when such a device is sold and things go wrong for some reason?
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Hi i see. Speaking of diy projects the mains transformer can always be housed in a separated wooden box ? and a 3 wires umbilical cord to the case containing the amp circuits ? 🙄
Yes, using the 2-prong connector is better than using an IEC C-13.14 3-prong connector without connecting the ground. You can still get some fancy 2-core mains cable.
Scroll down this page for diagrams illustrating the IEC male/female connector range -
IEC 60320 - Wikipedia
Scroll down this page for diagrams illustrating the IEC male/female connector range -
IEC 60320 - Wikipedia
Hi and thanks a lot for your kind reply. So i am not the only one hating captive cords 🙂 but not umbilicals
I see more and more commercial new amps coming with a 2 wires power cord and Class II 🙄 Even very expensive ones.
There must be a reason for tis design choice. Maybe is the one you mention ?
very interesting. But where do you connect the cable shield ? to the audio ground ?
i love your approach. And it is what i would like to do. For me IEC sockets should be made mandatory. Or the norm like with computers and peripherals. I do not like any tail protuding from an amp ... 🙁
Ginetto it is all about producing stuff as cheap as possible while still being relatively safe. The glory days of quality audio are more or less over.
Plastic is cheaper than metal.....
Plastic is cheaper than metal.....
Yes but only saving money where this does not impact performance too much.
For instance i am looking at the new products from Japanese top brands ... integrateds and separates. They look gorgeous. And i guess this look costs. I would much prefer an anonimous rack but with a great amp inside ... like this for instance
i do not look at a system ... i tend to listen to it 🙄
Instead i like to look inside equipment ... a lot
Even if my eye is not trained.
possibly more than relatively 😱
someone has done that already
An externally hosted image should be here but it was not working when we last tested it.
i put one small preamp once in a small rigid plastic transparent box for food Some polycarbonate or similar ?
It was a problem to drill for connections and volume pot ... very fragile
Only after cracking it i discovered a tutorial
What i like of plastics is that they isolate perfectly.
For power amps it is impossible for the weight
When replacing any 'figure 8' socket and cord to an IEC type, I use a metal nibbler tool to work around the previous hole to fit the new IEC socket. No fine drill fragments to worry about with using the nibbler. I prefer filtered socket ones and if space permits with a built in fuse in the socket. You can still use the IEC cord to either the gear is grounded or not, as previously with the older AC socket.
1 Pascal=94dB
1 Pascal=94dB
Hi ! thanks and very interesting. Do you have a brand and model to suggest ?
are they expensive ? thanks
This is what I used, there are better ones on RScomponents $$.
Nibbling Tool | Jaycar Electronics
Nibbling Tool | Jaycar Electronics
An externally hosted image should be here but it was not working when we last tested it.
Hi Thanks a lot ! i will try one asap i really cannot stand captive cord. I know there is a point of contact more ... and i confess i also like to play a little with cables 😱
and cheap but fancy plugs 😀 for instance about iec plug the ones found on ebay are easier to use and with receptacles good also for thick wires.
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You have absolutely right but it works only if you have a 30mA diff protection device at home. Clo-clo (Claude François) didn't know that but now we know 😉
Guys, in each elektor magazine, there is a dedicated page about safety. I have only the French version but it should easy to find the US version (search for a magazine in the same year of french version, february 2011 for example).
The resistor between PE pin (of the IEC inlet) and chassis simply is against all regulations and safety rules regardless if the home has either fuses or RCD's. Don't even think of doing this. PE should always be connected directly to chassis in all Class I devices. Audio GND is a separate item.
I am glad you advise on the Elektor safety pages, these give valuable information. They're adapted to the country where the magazine is sold AFAIK.
I am glad you advise on the Elektor safety pages, these give valuable information. They're adapted to the country where the magazine is sold AFAIK.
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Shielded IEC leads has mains three-core power cord, which is connected to the power plug and the IEC plug in the conventional way. This cable also has a braided shield around it. It is connected to the earth pin in the mains socket, along with the green ground wire. It is not connected to anything at the IEC end. It is called a "floating ground". See diagram here
DIY Belden 83803 Mains Power Cable - Audiophile Power Cord
If you do construct your own mains cables make sure that they are properly insulated. I would strongly recommend that before using them that you get a qualified test+tagger to check them with a PAT tester - this will check they are wired correctly/safely, and check for insulation leakage, etc. Remember, a mistake could be a deadly mistake with mains power, if not deadly for you, it might be deadly for someone you care about.
In the US it's a Ground Fault Circuit Interrupter (GFCI). It's much more sensitive at 5 to 6 mA leakage current. They are available everywhere as circuit breakers or replacement dual receptacles.
Thank you for information 😉
In France, because the new electronics parts have less earth leakage current, it is about 15mA but the name "30mA" stays 😉 -> you have a better protection because at 15mA, the current can kill. Not at 5-6mA !
In France, because the new electronics parts have less earth leakage current, it is about 15mA but the name "30mA" stays 😉 -> you have a better protection because at 15mA, the current can kill. Not at 5-6mA !
Yes the same devices all based on an invention by a chap called Schuckert in Germany (Europe) in 1903 with the name Summenstromschaltung zur Erdschlußerfassung. In a few areas in the world where 115V 60 Hz mains voltage is used instead of the more standard 230V 50 Hz twice the current should be delivered also through way thicker cables as P = U x I. With thicker cabling/more copper and higher possible current mains impedance can be quite low too. As humans die from current mainly ...... RCD's or GFCI's need to be adapted.
Of course these devices only work OK when there actually IS a PE connection...and the DIYer on duty is aware that PE is there to save lives and follows safety rules. GFCI's/RCD's for whatever the same devices are called in whatever area belong to the electric items that are rarely understood 100%, certainly by laymen.
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Please check on that.
I know a GFI will trip with no PE in sight-- it is a *differential* leakage detector. Also (in the US) a GFI without a green (PE) wire is an approvable and suggested solution for safety where a PE can not be reasonably provided. A GFI will trip-out properly on a floating source (engine-generator on rubber tires).
Depends on how you explain it. Please see the picture. English is not my language so keep that in mind. We could continue in one of my languages though 🙂
It is, for instance, a person that is the connection/path to ground/PE thereby creating a difference in currents ... otherwise it is a differential circuit yes. If the person would float in the air or be fully isolated then not much would happen. If the ground/floor would be fully isolated also not much would happen I guess.
It is, for instance, a person that is the connection/path to ground/PE thereby creating a difference in currents ... otherwise it is a differential circuit yes. If the person would float in the air or be fully isolated then not much would happen. If the ground/floor would be fully isolated also not much would happen I guess.
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If the person were floating in the air, like a bird on a power line, nothing would happen, no shock.