Mains Noise Suppression - Page 2 - diyAudio
Go Back   Home > Forums > General Interest > Everything Else

Everything Else Anything related to audio / video / electronics etc) BUT remember- we have many new forums where your thread may now fit! .... Parts, Equipment & Tools, Construction Tips, Software Tools......

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 24th July 2010, 04:50 PM   #11
tinitus is offline tinitus  Europe
diyAudio Moderator R.I.P.
 
Join Date: Nov 2005
We have two kinds of voltage here
230V fore normal domestic electronic
Wall sockets are 3pin with earthing
Electronics are always with 2pin connectors without specicfic orientattion
400V fore professional workshops, with 5pin connectors and earthing
Fore stationary machines, or heavy portable machinery

Its true, lots of hifi does have a round 2pin connector with additional earthing on the side of the connectors
But the only approved wall socket here is 3pin
Yeah, a strange thing really
__________________
sometimes we know very little, and sometimes we know too much
  Reply With Quote
Old 24th July 2010, 06:26 PM   #12
tinitus is offline tinitus  Europe
diyAudio Moderator R.I.P.
 
Join Date: Nov 2005
Quote:
Originally Posted by jean-paul View Post
All computer power supplies are designed with a noise filter in them so no need for an extra filter. They do need safety earth/ground for filtering and safety.
Might well be the problem on hand

Below is a picture of the 3pin wall socket used around here, and the only legal one

Strangely its now common that electronics use another kind of international 2pin mains cable
Used a lot fore hifi
Maybe better known as Schuko
My PC actually does have this kind of plug
As do the charger fore my portable PC

Matching wall socket would the blue one(picture)


So, I need to find some kind of adaptor, or cut the cable and mount other 3pin plug, or build a custom connector box

Man, no wonder theres so much noise on our mains
Attached Images
File Type: jpg vægdåse.jpg (22.1 KB, 182 views)
File Type: jpg Schuko socket p107_2_image.jpg (7.6 KB, 177 views)
__________________
sometimes we know very little, and sometimes we know too much
  Reply With Quote
Old 24th July 2010, 08:56 PM   #13
diyAudio Member
 
Speedskater's Avatar
 
Join Date: Sep 2002
Location: Lakewood, Ohio
Normally it's best to put a filter near the source of the noise. Often these filters are a resistor and capacitor in series. I know that I saw one on the web recently, but now I can't find the link.
__________________
Kevin
  Reply With Quote
Old 25th July 2010, 12:45 PM   #14
diyAudio Moderator Emeritus
 
jean-paul's Avatar
 
Join Date: Sep 2002
Location: Germany
Quote:
Originally Posted by tinitus View Post
Might well be the problem on hand

Below is a picture of the 3pin wall socket used around here, and the only legal one

Strangely its now common that electronics use another kind of international 2pin mains cable
Used a lot fore hifi
Maybe better known as Schuko
My PC actually does have this kind of plug
As do the charger fore my portable PC

Matching wall socket would the blue one(picture)


So, I need to find some kind of adaptor, or cut the cable and mount other 3pin plug, or build a custom connector box

Man, no wonder theres so much noise on our mains

Hi, if the left version (which I've never seen before) uses only the 2 pins then regulations in your country are plain unsafe. I see there is a third opening which appears to have a third pin to "earth" but since all standard cables in the EU use the outer contacts it still won't help much. As seen before a countries own standards will only end up in more costs and confusion since the majority uses the real standard types which of course will be cheaper as they're produced in much larger numbers. Besides that this is pretty unsafe as it is now, certainly if the organization that defines the standards in your country allow stuff to be imported with the Schuko plugs. In fact this seems such a serious safety problem that I would call that organization to reconsider safety regulations if I were a citizen like you living there. I am sure you get shocks when touching metal parts of computers in your country for the reasons I posted earlier. This can easily be measured with a DMM between case and PE/safety ground. There will be 115 V AC on the case if 230V is the voltage..

The right one is the standard Schuko that should be used in most European countries except for the UK with their ... eh, special plugs. When you use the right one (of course with the side contacts connected to PE/safety earth) you won't have problems.

Are you from one of the "newer" EU countries ? Just curious as the Schuko is standard for a very long time now. Although I normally would not advise to use stuff that is not allowed in this specific case I do advise to use the standard proven Schuko wall outlet with the side contacts. My motivation for this is that it would be way safer for you and your family. Best would be to remove the odd wall outlet and have it replaced for a Schuko one. While you are at it you could also change those in the rest of your house like the ones used at moist areas like the kitchen, the washing machine etc. Never use Schuko connectors that have side "earth" contacts without connecting those to safety ground/"earth"/PE !! So you have to have your electrician make sure the third pin in the now used outlets really is connected to PE.
__________________
It's only audio. Official member of the Norske Brillegeit Gang.

Last edited by jean-paul; 25th July 2010 at 01:14 PM.
  Reply With Quote
Old 25th July 2010, 02:31 PM   #15
wwenze is offline wwenze  Singapore
diyAudio Member
 
Join Date: Mar 2008
tinitus are you from Denmark?

AC power plugs and sockets - Wikipedia, the free encyclopedia

I'd buy a ton of that type of plug and replace all the wires with that.
  Reply With Quote
Old 25th July 2010, 02:49 PM   #16
diyAudio Moderator Emeritus
 
jean-paul's Avatar
 
Join Date: Sep 2002
Location: Germany
Quote:
Type K (Danish standard)

As of 1 July 2008, wall outlets for type E (French 2-pin, female earth) are permitted for installations in Denmark [22]. This was done because no electrical equipment sold to private users is equipped with a type K plug, and to break the monopoly of Lauritz Knudsen — the only company making type K sockets and plugs.

Sockets for the Schuko F type will not be permitted. The reason is that a large number of currently used Danish plugs (coincidentally made by the afore mentioned Lauritz Knudsen monopoly) will jam when inserted into a Schuko socket. This may cause damage to the socket. It may also result in a bad connection of the pins, with resultant risk of overheating and fire. Broken type F sockets are often seen in German hotels visited by Danes.[citation needed] Many international travel adapter sets sold outside Denmark match type C CEE 7/16 (Europlug) and type E/F CEE 7/7 (Schuko-French hybrid) plugs which can readily be used in Denmark.

What a mess ! The webpage shows a lot of types used in Europe but nowadays the Schuko type F is very common (not only in Europe).
__________________
It's only audio. Official member of the Norske Brillegeit Gang.

Last edited by jean-paul; 25th July 2010 at 03:02 PM.
  Reply With Quote
Old 25th July 2010, 02:53 PM   #17
Pano is offline Pano  United States
diyAudio Moderator
 
Pano's Avatar
 
Join Date: Oct 2004
Location: Milliways
Blog Entries: 4
Default Every country is different

Since we don't know the codes and practices in Tinitus' country, we don't know how his system is wired. He needs to find out what are the codes and standard practices there. His house may not comply, if it's old.

Having had my hands on wiring in the USA, Canada, Mexico, UK, France, Germany, Italy and Russia _ I can tell you that everyone does it differently. And everyone thinks their way is "best."

In the USA (and Canada, AFAIK) it's simple. Domestic power comes from the step down transformer on the street. The secondary of this transformer is 240V center tapped. The center tap is connected to earth at the transformer which is usually up on a pole. That earth connected center tap becomes what we call the "Bonded Neutral". It is at ground potential. It is connected to ground again at the service entrance to your house. The reason the neutral is bonded to ground is safety.

So we have 2 hot wires and one neutral. Between the 2 hots is 240 volts. Between either hot and neutral is 120V. Since neutral is bonded to ground, so either hot wire to ground is also 120V. Typically we use 1 hot and the neutral for our household devices. 2 hots will be used for the 240V devices such as watter heaters, clothes dryers, heat and air.

In the 1960s we added the ground wire. So now we have 3 wires. The ground wire mainly protects from voltage spikes, such as lightening strikes, but also acts as an additional drain to ground. Because current does flow in the neutral wire (it's 1/2 the circuit) it can sometimes be above ground potential. The ground wire normally carries no current, so "should" always be at ground potential. That makes it a nice drain for noise.

In other countries things are not done the same way. So you have to know what your countries codes and practices are. Consult a code book. Do not just ask, must people don't have a clue. Even some electricians don't. Once you know how things are supposed to be in you area, check to see if your house is really wired that way.
__________________
Take the Speaker Voltage Test!
  Reply With Quote
Old 25th July 2010, 02:59 PM   #18
diyAudio Moderator Emeritus
 
jean-paul's Avatar
 
Join Date: Sep 2002
Location: Germany
"Best" is not very impressive, "safe" and "standard" are. It is not a problem if a country chooses an own standard that they think is "best". If they do they should not allow foreign domestic appliances to be sold with "wrong" plugs that could cause harm to their people.

I have seen the same in countries with the british wall outlets and european Schuko type F cables on domestic appliances that are sold there. What will people do ? They use a ballpoint pen and force the Schuko plug in the british connector. It is matter of either joining international standards or an own "best" system with all imported appliances using the own "best" plug. If Schuko F type wall outlets are forbidden how-come computers can be sold with Schuko/IEC cables ?

The system panomaniac describes is the same here but here a 3 phase system (so 3 hot wires and a neutral) is used with ground. Between L and N there is 230V. Between the 3 phases (then called L1,L2 and L3) there is 400V. A special 3 phase CEE form connector is used in industrial environments for heavy equipment requiring 3 phase power. All supply wiring till 10 kV is in the ground and transformers are in special houses and not on poles as they earned the hard way that poles with transformers are a good recipe for black outs.
__________________
It's only audio. Official member of the Norske Brillegeit Gang.

Last edited by jean-paul; 25th July 2010 at 03:25 PM.
  Reply With Quote
Old 25th July 2010, 04:23 PM   #19
diyAudio Member
 
Juergen Knoop's Avatar
 
Join Date: Jan 2007
Blog Entries: 3
Quote:
Originally Posted by tinitus View Post
Might well be the problem on hand

Below is a picture of the 3pin wall socket used around here, and the only legal one

Strangely its now common that electronics use another kind of international 2pin mains cable
Used a lot fore hifi
Maybe better known as Schuko
My PC actually does have this kind of plug
As do the charger fore my portable PC

Matching wall socket would the blue one(picture)


So, I need to find some kind of adaptor, or cut the cable and mount other 3pin plug, or build a custom connector box

Man, no wonder theres so much noise on our mains
I'm not shure if I understand you correctly. Schuko provides a threewire connection i.e. live, neutral and protective earth.
Two wire connections are used with safe insulated equipment only and come in europe with so called 'euro plugs' and cables.
Anyway, do you live in an EU country? I'm pretty shure that all electronic equipment sold in EU countries must comply with the national electrical safety and wiring standards. That includes the local used plugs.
So, if you haven't imported the things yourself or bought 'fell from a truck', you should ask your dealer for a proper mains cable or at least a suitable adaptor.
regards
  Reply With Quote
Old 25th July 2010, 05:15 PM   #20
diyAudio Member
 
zigzagflux's Avatar
 
Join Date: Oct 2006
Location: Charlotte, NC
Quote:
Originally Posted by jean-paul View Post
All supply wiring till 10 kV is in the ground and transformers are in special houses and not on poles as they earned the hard way that poles with transformers are a good recipe for black outs.
And we learned here that underground equipment is frequently underwater, therefore is a good recipe for black outs. As you say, there is no 'best'.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
newbie - Kenwood 3020SE mains noise? jimh0612 Solid State 24 13th November 2012 09:33 AM
Wich Suppression Capacitor to block Mains emi? samsagaz Solid State 26 13th November 2010 10:53 AM
Low Frequency Mains Noise ruffrecords Tubes / Valves 6 31st October 2008 07:26 PM
Noise suppression bypass caps on Si bridge Steerpike Power Supplies 2 23rd July 2008 09:33 PM
LM3886 very prone to mains noise Andypairo Chip Amps 26 14th April 2005 02:51 PM


New To Site? Need Help?

All times are GMT. The time now is 09:51 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2