Author Topic: can you do something for me ?  (Read 10225 times)

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Offline Simon

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can you do something for me ?
« on: June 15, 2011, 05:25:30 am »
Tell the fuckwits that design wallwarts with the wire coming out from the earth[in side that they need to stop doing it like that !

seriously, what the hell is it with these people. We have always had plug and adapter wires coming from the 2 pin side of the (British) plug not the earth pin side. And no it aint artistic to look at a socket bar with wires going in opposite directions ! The last straw came when I tried to plug my phone power wupply into a 3way adapter, yes you guessed it, now the wire crashes into the socket face. I mean what are these people on ?

If you know a wallwart designer please tell him a thing or two on my behalf

/rant over

Sorry just had too, got other stuff on me plate too, it's not that I'm bored  >:(
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Offline firewalker

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Re: can you do something for me ?
« Reply #1 on: June 15, 2011, 06:34:33 am »
Any photos? I can't really understand it.
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Offline Simon

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Re: can you do something for me ?
« Reply #2 on: June 15, 2011, 06:44:50 am »
the british plug is square, the pins in the back are in a triangle, the one on top is the earth, the wire always used to come out of the bottom, some idiots have the wire out of the top, simply put: the reverse of the norm
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Offline firewalker

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Re: can you do something for me ?
« Reply #3 on: June 15, 2011, 07:27:32 am »
A, ok. Got it!
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Offline Vertigo

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Re: can you do something for me ?
« Reply #4 on: June 15, 2011, 07:44:19 am »
maybe allot of brittish homes have wall sockets very close to the floor?
 

Offline Simon

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Re: can you do something for me ?
« Reply #5 on: June 15, 2011, 03:37:11 pm »
you cannot come lower than the skirting board and the smallest skirting board is 3 inchs (76mm) It just amazes me that something that has been a standard for over 50 years is being pulled to pieces and causes havoc
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Offline FreeThinker

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Re: can you do something for me ?
« Reply #6 on: June 15, 2011, 05:23:59 pm »
A quick sort through my selection of power packs (mobile phone, mp3 player, camera, video camera etc.) shows a 50/50 spread of top to bottom outlets. I suppose it depends on installation but in reality a safe bet would be that there would be more room above the socket than below so top outlet would be a good idea in most cases but like all rules of thumb exceptions will catch you out. While the standard 3 pin plug does indeed always exit at the bottom, I have found in numerous cases (mainly office cubes with power trunking on the walls at desk height) that bottom exits cause too tight a bend on the cable because the sockets are not high enough above the desk, perhaps we should standardise on top outlets?
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Offline FreeThinker

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Re: can you do something for me ?
« Reply #7 on: June 15, 2011, 05:30:48 pm »
you cannot come lower than the skirting board and the smallest skirting board is 3 inchs (76mm) It just amazes me that something that has been a standard for over 50 years is being pulled to pieces and causes havoc
I think the code of practice recommends that sockets are mounted at least 300mm above FFL (finished floor level) but older installations are often much lower than this. Indeed I have seem MANY sockets mounted on skirting boards, with little more than 25mm to FFL.
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Offline Simon

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Re: can you do something for me ?
« Reply #8 on: June 15, 2011, 09:51:57 pm »
well offices should not have sockets set up so, do we now want wires flying up and all over a desk ? if I was putting sockets over a desk I'd make sure there was room for the wires and possibly a slot behind the desk so that they can go out of the way
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Offline GrumpyDave

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Re: can you do something for me ?
« Reply #9 on: June 15, 2011, 10:10:47 pm »
The majority of mains adaptors in my home are lower than the appliance they power so cable out the top is not such a bad idea.

However at work on the bench down is better, to be honest I have never really it given much thought..
 

Offline FreeThinker

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Re: can you do something for me ?
« Reply #10 on: June 15, 2011, 11:57:14 pm »
well offices should not have sockets set up so, do we now want wires flying up and all over a desk ? if I was putting sockets over a desk I'd make sure there was room for the wires and possibly a slot behind the desk so that they can go out of the way
In a perfect world I would agree, but until the revolution we need to live in the real world. Many office installations have service ducts in the floor with little trapdoors covering the sockets, the idea being that a desk is placed over the flap and cables ran down the back of the desk to the outlets. Cables are tidy and neat. The reality is that the outlet usually falls in the aisle between desks (sods law) and cables trail across the floor to the desk looking ugly and are a trip hazard. Enter the rubber cable tidy strip and the aisle suddenly turns into a traffic calming area with speed bumps every 2 yards :D.
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Offline hannobisschoff

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Re: can you do something for me ?
« Reply #11 on: June 16, 2011, 01:18:07 am »
Normally people interested in electronics are not very set upon aesthetics.
 

Offline Sionyn

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Re: can you do something for me ?
« Reply #12 on: June 16, 2011, 07:16:52 am »
its a eu thing again and access for disabled with hight of wall sockets

agree on wall warts very badly designed with the wire from the top

i dont know maybe some doggy focus group decided that it was better coming through the top ?
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Offline Vertigo

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Re: can you do something for me ?
« Reply #13 on: June 18, 2011, 01:21:07 pm »
imo its poorly designed to even have a top.

regular euro plugs are fully ambidextrous.



now thats a manly plug  8) :P
 

Online Zero999

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Re: can you do something for me ?
« Reply #14 on: June 18, 2011, 06:58:55 pm »
imo its poorly designed to even have a top.

regular euro plugs are fully ambidextrous.
I agree, having the lead on top is a good idea but that's the only good thing about European plugs which are otherwise inferior to UK plugs, no fuse, non-polarised and no safety shutter on the earth pin.
 

Offline Vertigo

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Re: can you do something for me ?
« Reply #15 on: June 18, 2011, 09:42:16 pm »
oh please, i have never heard of anyone having a problem because there was no safety shutter.
such things are entirely redundant with a properly designed plug.
sounds rather redundant to me.

as for fuses, i dunno how it works where u live, but here we have our entire mains
heavily fused.
so we have fuses in the wall and in our devices, no need to have them in the plug.

though i will say some people use extension cords with filters on them to power computers
because of potential peaks and power outages etc.
something like that might be useful for people who run computers with a substandard PSU.

 

Offline Simon

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Re: can you do something for me ?
« Reply #16 on: June 18, 2011, 11:33:15 pm »
the idea of the shutter is to stop things being poked into the socket and has nothing to do with the plug. The european plug does not have a live and neutral as it can be reversed. wall warts should be made like the plugs they replicate that have been in use of well over 1/2 a century. there is no advantage to disabled people in having a wire coming out of the other side. It's was just some dickhead designer that thought he would be different.
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Online Zero999

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Re: can you do something for me ?
« Reply #17 on: June 19, 2011, 12:59:26 am »
Having a fuse in the plug is very good for safety because the circuit breaker in the house will be too large to provide adequate protection for the cable and equipment connected to the plug. The European plug design makes is hard, if not impossible to have a safety shutter in the socket because of the positioning of the pins

Being non-polarised is bad because the live wire could be connected to either conductor so class 3 equipment will need two fuses to protect it against short circuit and the switch will need to be two pole to isolate the appliance from the mains.
 

Offline Vertigo

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Re: can you do something for me ?
« Reply #18 on: June 20, 2011, 06:47:47 am »
meh, it still looks better :P
 

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Re: can you do something for me ?
« Reply #19 on: June 20, 2011, 07:07:33 am »
The UK plug is far superior to the European schuko plug from an electical and mechanical point of view and I grew up with Schuko plugs and also these ones for Class 2 devices: http://www.cordsncables.co.uk/acatalog/4-189%20Col%20online%20cat.jpg

Now, what I find really scary is the American plugs: http://www.sjndreams.com/WebFiles/3_AMERICA/FLORIDA/FloridaPLUG.jpg

They also use half the voltage (110V AC) so the devices draw double the current for the same power (ignore power factors now..) yet the American plugs are much thinner than the European ones, not to mention the UK ones (both on 240V AC). I mean, I have seen Christmas lights with more beefy plugs...
 

Offline Simon

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Re: can you do something for me ?
« Reply #20 on: June 20, 2011, 07:17:54 am »
I also spent 14 years with shuko and european plugs: garbage......
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Re: can you do something for me ?
« Reply #21 on: June 20, 2011, 07:19:46 am »
But they were good years, now with the UK plugs all the fun is gone, you know nothing can go wrong  ::)
 

Offline Simon

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Re: can you do something for me ?
« Reply #22 on: June 20, 2011, 07:25:17 am »
well put it this way: I no longer have to cut earth pins out of plugs on extensions i made for old ladies so that they will fit a 40 year old socket with no earth pin while telling them "I didn't do this".....
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Offline ziq8tsi

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Re: can you do something for me ?
« Reply #23 on: June 20, 2011, 08:16:48 am »
Having a fuse in the plug is very good for safety because the circuit breaker in the house will be too large to provide adequate protection for the cable and equipment connected to the plug.

But that is only true in the UK because of post-war copper-saving, where pairs of 15A radial circuits were allowed to be joined together to form 30A rings.  In most of Europe, sockets are wired on 16A circuits, which actually provides better protection against flex fires than a BS1363 plug with 13A fuse.  (Because a 16A MCB breaks faster for small overloads than a 13A BS1362 fuse, and because the breaker is for the whole circuit, not just the faulty device.)

A BS1363 plug with a 3A fuse theoretically provides much better protection for the flex.  But the user might not fit one.  In any case, harmonized European regulations do not permit appliances to be sold with thin flexes that could not carry a 16A fault current for a short time.

Quote
Being non-polarised is bad because the live wire could be connected to either conductor so class 3 equipment will need two fuses to protect it against short circuit and the switch will need to be two pole to isolate the appliance from the mains.

Class III is SELV.  All appliances, even if polarized, should treat the live and neutral as equally hazardous, since the neutral becomes live if it is accidentally severed upstream.  Having two fuses would be pointless since you do not know which will blow first.  Unless you are thinking of a fault to earth in a Class I device, in which case any fusing does not matter as long as the earth conductor is adequate.

The shutters on UK sockets are a nice feature, though arguably only necessary because of the huge pin sizes.  But the system has bad points too.  The risk of foot injury.  The fact that if the plug is smashed or comes unscrewed then live parts are exposed and it is very difficult to remove safely.  (Rewireable plugs with rear cable entry tend to screw together sideways instead.)  The fact that chained extensions include multiple redundant fuses, which makes the system unusable in industries such as stage lighting.

Regarding UK wall-warts, what annoys me far more than cable routing is the crappy plastic earth pins that many of them have.  I cannot understand why these are allowed.  I have actually witnessed one snap off and stay in the socket when the plug was removed, thereby leaving the socket disabled and with its shutters open.
 

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Re: can you do something for me ?
« Reply #24 on: June 20, 2011, 08:33:38 am »
All appliances, even if polarized, should treat the live and neutral as equally hazardous, since the neutral becomes live if it is accidentally severed upstream.

Sure, all safety measures can fail with effort. According to the regulations in EU and/or UK, is it legal for the manufacturer to use a single pole switch and place that in line with the live conductor, thus making an assumption as to which one will be the live conductor? What switch (single or dual pole) is legal for a Class 1 and Class 2 device?

 

Online Zero999

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Re: can you do something for me ?
« Reply #25 on: June 20, 2011, 08:45:43 am »
But that is only true in the UK because of post-war copper-saving, where pairs of 15A radial circuits were allowed to be joined together to form 30A rings.  In most of Europe, sockets are wired on 16A circuits, which actually provides better protection against flex fires than a BS1363 plug with 13A fuse.  (Because a 16A MCB breaks faster for small overloads than a 13A BS1362 fuse, and because the breaker is for the whole circuit, not just the faulty device.)
That maybe so but then there's the disadvantage of not being able to connect two large appliances to neighbouring sockets so if the toaster and kettle were connected to the same circuit, the breaker would blow when they're both turned on. The 13A system is also more convenient because it's obvious where the fault lies, the house breaker tripping would be a pain because you'd have to unplug each device until the faulty one is located.

Quote
A BS1363 plug with a 3A fuse theoretically provides much better protection for the flex.  But the user might not fit one.  In any case, harmonized European regulations do not permit appliances to be sold with thin flexes that could not carry a 16A fault current for a short time.
I wouldn't agree that 0.5mm2 cable or even 0.752mm cable is sufficient for a 16A circuit.

Quote
Class III is SELV.  All appliances, even if polarized, should treat the live and neutral as equally hazardous, since the neutral becomes live if it is accidentally severed upstream.  Having two fuses would be pointless since you do not know which will blow first.  Unless you are thinking of a fault to earth in a Class I device, in which case any fusing does not matter as long as the earth conductor is adequate.
Yes, I meant class 1.

Although the live and neutral are both hazardous, fusing the neutral, rather than the live is a bad idea because when the fuse blows, the appliance is certainly live. If the live only were fused, the appliance will probably be safe when the fuse blows, although, as you say, there's the remote possibility the neutral has also been broken. This is why the fuse is always fitted in on the live conductor and having a non-polarised plug is bad because it defeats this.

Quote
The shutters on UK sockets are a nice feature, though arguably only necessary because of the huge pin sizes.  But the system has bad points too.  The risk of foot injury.  The fact that if the plug is smashed or comes unscrewed then live parts are exposed and it is very difficult to remove safely.  (Rewireable plugs with rear cable entry tend to screw together sideways instead.)
You're right, it's not perfect and I've stood on plugs in the dark before ouch!

Quote
The fact that chained extensions include multiple redundant fuses, which makes the system unusable in industries such as stage lighting.
I'm not sure how this is any worse than not being able to identify which appliance is faulty when all the sockets in a room go dead because of one faulty appliance.

Quote
Regarding UK wall-warts, what annoys me far more than cable routing is the crappy plastic earth pins that many of them have.  I cannot understand why these are allowed.  I have actually witnessed one snap off and stay in the socket when the plug was removed, thereby leaving the socket disabled and with its shutters open.
I've had that problem too.

Actually, I think if we're to harmonise, a totally new plug should be designed combining the advantages of both the European and UK systems. I'd definitely want to keep the fuse, polarisation and safety shutter but the maximum current could be increased to 16A, the connections made from the rear of the plug to reduce the risk of foot injury and the plug should unscrew from the side, not the bottom.
 

Online vk6zgo

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Re: can you do something for me ?
« Reply #26 on: June 20, 2011, 10:56:28 am »
Although I recognise the advantages of the UK style plug,it just seems too "clunky".
The fuse in the plug does die with age, & domestic appliances  are unnecessarily replaced at extra expense,when it is just an "aged" fuse.

Although it does have issues,I prefer the Australian standard plug.
It is light, convenient,fulfils all the requirements of a 240v plug,except the standard orientation is reversed
to what would be logical--earth  pin is at the bottom instead of the top.
The standard cable outlet on an Australian plug is at the rear of the plug (in line with the pins).
The standard material is heavy duty flexible PVC.

It is just as easy to hurt bare feet with an Aussie plug as with a UK one, though,in fact the pins are sharper!!

Have you ever had a play with a US 240v 20A plug?
They are incredibly over-engineered!

In the USA,the 240v supply is from a centre-tapped pole transformer with both sides  being "hot" w.r.t neutral
(& earth),hence ,you find equipment with fuses in both sides.I think this is actually illegal in Australia,but equipment wired this way is common among USA & Canadian sourced equipment.

I bought a shortwave radio many years ago, which was equipped with a 2 wire power cord.
This was a 240 volt device, but was designed for the US system.

It had an RF filter circuit on the AC mains input,with capacitors from both legs to the chassis,which in the USA
would be a "virtual earth".
In Australia,the chassis was tapped halfway down a capacitive voltage divider,so when ,in my eagerness,I attached an aerial & earth,the earth lead went "zap"!
Not enough current to do any harm to a person,but if I had attached any other equipment,it might not have
survived its first introduction to the new radio! ;D

Needless to say, the first "mod" was a three core power cable!

VK6ZGO
 

Offline Lance

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Re: can you do something for me ?
« Reply #27 on: June 20, 2011, 12:54:58 pm »
Simon I'm having a hard time visualizing what you're saying up in the OP. Can you post a picture or two?
#include "main.h"
#include <pic.h>
//#include <killallhumans.h>
 

Offline Simon

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Re: can you do something for me ?
« Reply #28 on: June 20, 2011, 03:47:59 pm »
Simon I'm having a hard time visualizing what you're saying up in the OP. Can you post a picture or two?



now imagine having half your plus with a wire out of one side and half with it out of the other (opposite). Now think of wall warts made so, not fun eh ? either way a standard should be maintained.
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Offline firewalker

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Re: can you do something for me ?
« Reply #29 on: June 20, 2011, 09:55:41 pm »
Take a look at this!!!



A friend of mine told that one wall plug wasn't working normally. I bought a new one and tried to replace the old...

Alexander.
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Offline Lance

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Re: can you do something for me ?
« Reply #30 on: June 21, 2011, 01:57:58 am »
Simon I'm having a hard time visualizing what you're saying up in the OP. Can you post a picture or two?



now imagine having half your plus with a wire out of one side and half with it out of the other (opposite). Now think of wall warts made so, not fun eh ? either way a standard should be maintained.
Oh, I see. I agree! It would make everything fit together better. In canada everything either comes out of the back, or the bottom. Some of the slimmer adapters (like my cell phone charger) actually have the prongs mounted sideways so it doesn't cover up any other outlets.


Take a look at this!!!



A friend of mine told that one wall plug wasn't working normally. I bought a new one and tried to replace the old...

Alexander.
Eww.
« Last Edit: June 21, 2011, 01:59:54 am by Lance »
#include "main.h"
#include <pic.h>
//#include <killallhumans.h>
 

Online Zero999

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Re: can you do something for me ?
« Reply #31 on: June 21, 2011, 03:40:28 am »
Although I recognise the advantages of the UK style plug,it just seems too "clunky".
The fuse in the plug does die with age, & domestic appliances  are unnecessarily replaced at extra expense,when it is just an "aged" fuse.
I've never seen that happen before.

Fuses are rated for a minimum of 1000 hours at full load and most mains appliances draw much less current than the fuse rating. A TV may have a power rating of  70VA, drawing 0.3A but will be fitted with a 3A fuse which will never blow, unless there's a fault. Only larger appliances have a power rating nearer to the plug fuse but they tend to not be left on continuously so it is still not an issue.

Quote
I bought a shortwave radio many years ago, which was equipped with a 2 wire power cord.
This was a 240 volt device, but was designed for the US system.
Are you sure?

It seems odd that such a small device would be designed for 240V in the US. As far as I'm aware, in the US 240V is reserved for larger appliances such as washing machines, cookers and air conditioning units.

Quote
It had an RF filter circuit on the AC mains input,with capacitors from both legs to the chassis,which in the USA
would be a "virtual earth".
In Australia,the chassis was tapped halfway down a capacitive voltage divider,so when ,in my eagerness,I attached an aerial & earth,the earth lead went "zap"!
Not enough current to do any harm to a person,but if I had attached any other equipment,it might not have
survived its first introduction to the new radio! ;D

Needless to say, the first "mod" was a three core power cable!
The capacitors should be Y1 rated, otherwise it doesn't meet any safety legislation. That kind of configuration is actually quite common here in Europe. The capacitors are connected between both live and neutral to the case because some countries have a non-polarised plug. If they connected an X capacitor from live to neutral and a Y2 capacitor from the case to neutral, the cause might float at 230V, if it were connected to a dodgy non-polarised EU plug.

I don't like this kind of configuration, not only does it pose an ESD risk, it's also a serious shock risk (not just a tingle) if the chassis of many appliances are connected together because the leakage currents add.
 

Online vk6zgo

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Re: can you do something for me ?
« Reply #32 on: June 21, 2011, 04:14:45 pm »
Although I recognise the advantages of the UK style plug,it just seems too "clunky".
The fuse in the plug does die with age, & domestic appliances  are unnecessarily replaced at extra expense,when it is just an "aged" fuse.
I've never seen that happen before.

Fuses are rated for a minimum of 1000 hours at full load and most mains appliances draw much less current than the fuse rating. A TV may have a power rating of  70VA, drawing 0.3A but will be fitted with a 3A fuse which will never blow, unless there's a fault. Only larger appliances have a power rating nearer to the plug fuse but they tend to not be left on continuously so it is still not an issue.

You are probably correct,as I wasn't in the UK long enough to have a fuse die on me!
I have,however,read quite a few comments from UK based TV service people,who maintain this does happen,&
I have personally experienced fuse failure due to aging in other situations.


Quote
I bought a shortwave radio many years ago, which was equipped with a 2 wire power cord.
This was a 240 volt device, but was designed for the US system.
Are you sure?

It seems odd that such a small device would be designed for 240V in the US. As far as I'm aware, in the US 240V is reserved for larger appliances such as washing machines, cookers and air conditioning units.
Yes,I am sure.
Working in TV Studios & TV & Broadcast Transmitters,I have come across this kind of circuitry a number of times in 240volt US & Canadian sourced equipment.
My guess is that  240volt outlets are fairly common in TV studios in the USA,so that equipment for that voltage is made to the US standard.
Also US "Hams" commonly run linear amplifiers from 240volt as 120volt sockets usually are inadequate to supply enough current to run these devices at max legal power,so an HF receiver powered by 240volts is a possibility in that country.


Quote
It had an RF filter circuit on the AC mains input,with capacitors from both legs to the chassis,which in the USA
would be a "virtual earth".
In Australia,the chassis was tapped halfway down a capacitive voltage divider,so when ,in my eagerness,I attached an aerial & earth,the earth lead went "zap"!
Not enough current to do any harm to a person,but if I had attached any other equipment,it might not have
survived its first introduction to the new radio! ;D

Needless to say, the first "mod" was a three core power cable!

The capacitors should be Y1 rated, otherwise it doesn't meet any safety legislation. That kind of configuration is actually quite common here in Europe. The capacitors are connected between both live and neutral to the case because some countries have a non-polarised plug. If they connected an X capacitor from live to neutral and a Y2 capacitor from the case to neutral, the cause might float at 230V, if it were connected to a dodgy non-polarised EU plug.

In this case,the caps were only between both legs of the mains supply,so the maximum voltage present on the chassis w.r.t. neutral/earth if the caps don't fail is 120volts

I don't like this kind of configuration, not only does it pose an ESD risk, it's also a serious shock risk (not just a tingle) if the chassis of many appliances are connected together because the leakage currents add.

I definitely agree.When 2 wire cords were used back in the day,AC filters were not commonly used,so there
was less of  a problem.


VK6ZGO
« Last Edit: June 21, 2011, 06:51:59 pm by vk6zgo »
 


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