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Choosing a new soldering iron...
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Re: Choosing a new soldering iron...

by charliex on Fri May 21, 2010 8:25 pm

They've required fused plugs in the UK for long time.
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Re: Choosing a new soldering iron...

by sirket on Sat May 22, 2010 3:20 am

mojo wrote:Sounds nasty! I have an old 30W iron from a DIY shop that I used a couple of times on old audio gear with really bad corrosion, but all I did was remove the old solder and replace it. We get quite a few PCBs that have had liquid spilt on them at work (Coke is the worst) but we usually clean them up completely with an ultrasonic bath and then IPA before doing any soldering or hot air reworking.

An ultrasonic bath doesn't remove patina (copper oxide) from copper whereas an RMA or an RA flux will. There are lots of contaminants that a good flux will remove that normal cleansing will not. Components don't need to be antique to have oxide problems- systems in adverse environments like the marine and aerospace industries can have problems after just a few weeks.

I thought that was bad enough but now I feel lucky I don't have to deal with the nasty stuff you do ;-)

Thankfully it's not really nasty to me- just to the boards. Clean them with a flux remover like the stuff from TechSpray and you're good.

The OP was asking about an iron for hobby use and I can't see most hobbyists needing anything like that. I have worked on old audio gear as well as home and arcade game gear from the late 70s and not needed it.

I've added new components to unpopulated sections of old audio boards and the exposed copper was corroded enough to warrant a good RA Solder. Corroded battery terminals are another area where a good flux helps.

Again, ultrasonic cleaning is the best thing for that IME. If the pads are still dirty after cleaning with IPA (99% alcohol) then an eraser usually does the trick.

I think an ultrasonic bath, while incredibly useful, is also probably beyond most hobbiest budgets whereas a small pen of RA or RMA Flux is not.

Then again if I had the money I might be tempted to shell out for flux.

http://www.all-spec.com/products/Kester ... 18615.html
At $3.50 a pen It's probably within anyone's budget. I always keep a couple on hand just in case.

For the majority of my soldering I buy the Kester VOC Free No-Clean Flux by the gallon:
http://www.all-spec.com/products/Kester ... 97700.html

Interesting, do you have a reference for that? I'd love to read it.

Just the classes I had to take. Numerous other people who all mention NASA training also mention sponges:
http://www.nscale.net/forums/showpost.p ... stcount=13
http://acapella.harmony-central.com/sho ... stcount=10
http://www.rctech.net/forum/6489163-post1.html

At college we always used a sponge but I'm a brass convert now. I find that I can clean excess solder off the tip a lot more quickly and easily with it. I think the reason is that the temperature drop, however limited, makes the solder stick to the tip rather than drop off when using a sponge. It's similar to how if you want to bridge two pads on matrix board and you heat one pad first the solder often will not make the join, but if you heat both at the same time it does it easily. Maybe using an 18W iron exacerbates the problem but I like the low power for other reasons.

It's really not an either or situation- they both work- and they both serve similar purposes. The Brass is better for when you have contaminants that need a mild abrasive action to remove- or when doing a lot of soldering very quickly, one joint after another.

The sponge removes chemical contaminants as well as solder and other particulate contaminants- but it can cool the tip slightly. It shouldn't matter if the iron is decent, but this is another case where not using cold water helps reduce the drop. No it's not significant- but if you iron is weak- every bit helps.
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Re: Choosing a new soldering iron...

by sirket on Sat May 22, 2010 4:11 am

charliex wrote:That i wish i knew, the UK plug is so much better than the one in the USA, they're safer and better to rewire, they fit better and stay put.

The big problem in the States is that we have a hundred different types of plugs. 110v, 220v, 15amp, 20amp, 30amp, 50amp, single phase and three phase, Locking, and non-locking, etc.

Check out this absurd chart for our list of non-locking plugs:
http://www.jkem.com/pictures/NEMA%20Non ... 0Plugs.gif

There is another chart for locking plugs and those are pretty common here- especially in datacenters.

US 2 pin plugs definitely suck. The UK 3 prong plug is very similar to the US 3 prong plug- the opposed shafts make it a little more secure but not by much. If you compare the UK 240v 13amp plug (BS 1363) to the US 250v 15amp plugs (NEMA 6-15P) they are basically identical.

Fused plug is much more common in the UK too.

http://en.wikipedia.org/wiki/AC_power_p ... ets#Type_G
"The fuse is required to protect the cord, as British wiring standards allow very high-current ring main circuits to the socket."

We have plenty of devices with fuses/breakers in them- just not in the plug (My amateur radio gear, my stereo, my soldering station, my washing machine, etc.) Breaker/fuse use tends to be limited to devices that can fail in such a way as to draw more current than they are supposed to without causing a full short that would trip a regular panel breaker. A lot of devices also have internal fuses (both current and thermal) that reset automatically- for better or worse.

I remember moving over here and trying to find a blank plug to rewire something, they're just not as common either.

Here I have to disagree :) Every hardware store and home improvement center I've ever been in carries blank plugs.
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Re: Choosing a new soldering iron...

by charliex on Sat May 22, 2010 12:34 pm

sirket wrote:
charliex wrote:That i wish i knew, the UK plug is so much better than the one in the USA, they're safer and better to rewire, they fit better and stay put.

The big problem in the States is that we have a hundred different types of plugs. 110v, 220v, 15amp, 20amp, 30amp, 50amp, single phase and three phase, Locking, and non-locking, etc.

Check out this absurd chart for our list of non-locking plugs:
http://www.jkem.com/pictures/NEMA%20Non ... 0Plugs.gif

There is another chart for locking plugs and those are pretty common here- especially in datacenters.

US 2 pin plugs definitely suck. The UK 3 prong plug is very similar to the US 3 prong plug- the opposed shafts make it a little more secure but not by much. If you compare the UK 240v 13amp plug (BS 1363) to the US 250v 15amp plugs (NEMA 6-15P) they are basically identical.


Well the UK does have other plugs too, but in the home, you find the same balance as in the UK to the US.
Fused plug is much more common in the UK too.

http://en.wikipedia.org/wiki/AC_power_p ... ets#Type_G
"The fuse is required to protect the cord, as British wiring standards allow very high-current ring main circuits to the socket."

We have plenty of devices with fuses/breakers in them- just not in the plug (My amateur radio gear, my stereo, my soldering station, my washing machine, etc.) Breaker/fuse use tends to be limited to devices that can fail in such a way as to draw more current than they are supposed to without causing a full short that would trip a regular panel breaker. A lot of devices also have internal fuses (both current and thermal) that reset automatically- for better or worse.



Yes and everythings fused by the plug in the UK, as well as in the applicance itself. As well as the breakers too, so everything the US has, plus the fuses in the plugs.

Here I have to disagree :) Every hardware store and home improvement center I've ever been in carries blank plugs.


Then I'll ask are you aware how common spare plugs are in the UK ? They're sold just about everywhere, even in the corner shop. Not just in hardware/home improvement centres. You'll find a couple of types in those HW stores, and not that many of them. Certainly in my experience when i've gone to look for them, they're considerably less common and the ones i have found are very cheap, the plug form factor just doesn't lend itself as well as UK plug to rewiring either.


Given the choice, i'd ditch the US plug in a heartbeat and switch to the UK type, same goes for availability.
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Re: Choosing a new soldering iron...

by mojo on Sat May 22, 2010 5:41 pm

sirket wrote:I've added new components to unpopulated sections of old audio boards and the exposed copper was corroded enough to warrant a good RA Solder. Corroded battery terminals are another area where a good flux helps.


I have done a few of those at work. A little Cillit Bang works wonders but you do have to be careful with it. Otherwise the usual IPA and ultrasonic cleaning works, with an eraser to polish the cleaned contacts. Many a mobile phone or PDA has been revived that way.

I think an ultrasonic bath, while incredibly useful, is also probably beyond most hobbiest budgets whereas a small pen of RA or RMA Flux is not.


Mine was £5 in the sales. The larger one at work was about £50 but worth it as we use it quite a lot. Maybe you are thinking of something else?

At $3.50 a pen It's probably within anyone's budget. I always keep a couple on hand just in case.


Those are similar to what I use. From the way you were talking about it it sounded like you were referring to the stronger stuff that has to be properly cleaned up. I use that with just a brass sponge and it's fine, no residue, corrosion to loss of heat on the tip.

The pen based stuff is a lot less fluid than the bottled stuff. There are some (not very good) SMD soldering tutorials on YouTube where a guy uses it but he floods the board. It appears to work wonders but the amount of cleaning up offsets any benefits unless you are doing a lot of very fine pitch ICs IMHO. For normal SMD stuff the pen is perfect.

It's really not an either or situation- they both work- and they both serve similar purposes. The Brass is better for when you have contaminants that need a mild abrasive action to remove- or when doing a lot of soldering very quickly, one joint after another.


Funny, I would have put it the other way around! :-)

Seriously, brass seems to wear the tip a lot less than a sponge while being more effective at removing excess solder. Solder doesn't stick to brass but it does get pulled off by surface tension and then cools and drops to the bottom of the holder. In contrast a sponge tends not to pull solder away from the tip nearly as much. A sponge is obviously better for removing chemicals but brass is more suitable if you are just doing one joint after another on a fairly clean board.

I can work twice as fast when building things with brass because it perfectly removes excess solder every time with no effort where as a sponge requires a bit of work some times. I find that since moving to brass the actual iron and process of soldering is now secondary to building and developing circuits. I just don't have to think too much about it any more.

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Re: Choosing a new soldering iron...

by mojo on Sat May 22, 2010 5:50 pm

sirket wrote:We have plenty of devices with fuses/breakers in them- just not in the plug (My amateur radio gear, my stereo, my soldering station, my washing machine, etc.) Breaker/fuse use tends to be limited to devices that can fail in such a way as to draw more current than they are supposed to without causing a full short that would trip a regular panel breaker. A lot of devices also have internal fuses (both current and thermal) that reset automatically- for better or worse.


There are good reasons why we have fuses in the plugs. If the power cable gets damaged or there is some kind of catastrophic failure where the metal housing of an appliance becomes live the fuse will trip. It's better than having a fuse in the device because that fuse would not protect against any failure between it and the outlet socket. It also makes replacing fuses very easy. We have one type of plug for everything and use a 1A, 3A, 5A, 10A or 13A fuse as appropriate.

Maybe it's over-doing the safety aspect a bit, and I'm sure if it was a major problem other countries would consider switching... Well, actually as I understand it they are trying to harmonise the EU on three prong earthed, fused and switched plugs. Of course our use of ring mains and the kind of dodgy house wiring I mentioned earlier perhaps makes it more important here. The main distribution panel in my house still has fuse wire in it.

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Re: Choosing a new soldering iron...

by sirket on Sat May 22, 2010 11:41 pm

mojo wrote:There are good reasons why we have fuses in the plugs.

The reason you have them is the one listed on Wikipedia. A fuse in the plug only protects against one additional failure mode- that of a device drawing enough current to melt its wire without tripping the breaker for the outlet. US wiring is different in that our outlets, wall wiring, and plugs are all just generally rated to carry the breaker current. Any more than that and the breaker trips without melting the wire.

If the power cable gets damaged or there is some kind of catastrophic failure where the metal housing of an appliance becomes live the fuse will trip.

It wouldn't necessarily trip. You could have a voltage on the housing without a short occurring (Because of a bad cable with a broken ground for example). This is what GFCI breakers are for.

That said- if there is a catastrophic failure that causes the fuse to trip - then in the US- the breaker would trip.

It's better than having a fuse in the device because that fuse would not protect against any failure between it and the outlet socket. It also makes replacing fuses very easy. We have one type of plug for everything and use a 1A, 3A, 5A, 10A or 13A fuse as appropriate.

Again- the only thing that a fuse in the plug protects against is when the socket can deliver more current than the wire can handle- and the fault is in the wire itself, before the fuse in the device. That's rare enough, and coupled with the lower currents and larger number of smaller breakers in US houses- it's not a concern.

Of course our use of ring mains and the kind of dodgy house wiring I mentioned earlier perhaps makes it more important here. The main distribution panel in my house still has fuse wire in it.

The ring mains with 30-32 amp breakers is the reason you have fused plugs. In the US we used star topologies with 15 amp breakers. Since most wiring ends up being 14 gauge- there is no need for an additional fuse because the wiring can handle the full current supplied by the breaker.
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Re: Choosing a new soldering iron...

by sirket on Sat May 22, 2010 11:52 pm

charliex wrote:Well the UK does have other plugs too, but in the home, you find the same balance as in the UK to the US.

I certainly don't have a good appreciation for the balance of plugs in England but I never cease to be amazed at the plethora of plugs I come across here.

I suspect I'm an oddball case for NYC but I have 110v and 220v, 15, 20, 30 and 50amp sockets (The 50 is 220v only and is for my tig welder). Go out to the Midwest and you find lots of people with three-phase power for their big table saw or lathe.

Yes and everythings fused by the plug in the UK, as well as in the applicance itself. As well as the breakers too, so everything the US has, plus the fuses in the plugs.

Sure- but again- this is a function of the high current ring wiring you use. If you have 15amp breakers, and all your wiring, including devices is rated for 15 amp, then it serves no additional purpose.

Then I'll ask are you aware how common spare plugs are in the UK ? They're sold just about everywhere, even in the corner shop.

I'm not trying to say that they're more common here- just not hard to find either.

Certainly in my experience when i've gone to look for them, they're considerably less common and the ones i have found are very cheap, the plug form factor just doesn't lend itself as well as UK plug to rewiring either.

I have no doubt it's probably easier to rewire your plugs but you have to remember- this is the US we're talking about. Most people would rather just throw it out and buy a new one. Rampant consumerism and all that :(
Last edited by sirket on Sun May 23, 2010 6:49 pm, edited 1 time in total.
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Re: Choosing a new soldering iron...

by sirket on Sun May 23, 2010 12:10 am

mojo wrote:I have done a few of those at work. A little Cillit Bang works wonders but you do have to be careful with it. Otherwise the usual IPA and ultrasonic cleaning works, with an eraser to polish the cleaned contacts. Many a mobile phone or PDA has been revived that way.

I get a lot of boards with copper oxide corrosion and it's a pain to get off with an eraser. an RA flux will clean the pad right up without any effort. It's also useful in cases of lighter corrosion when I don't want to disassemble the project and put it in the ultrasonic bath.

Mine was £5 in the sales. The larger one at work was about £50 but worth it as we use it quite a lot. Maybe you are thinking of something else?

Mine was $450 but it's pretty big. I honestly haven't looked recently though so you're probably right.

Those are similar to what I use. From the way you were talking about it it sounded like you were referring to the stronger stuff that has to be properly cleaned up. I use that with just a brass sponge and it's fine, no residue, corrosion to loss of heat on the tip.

Any RA solder has to be cleaned up- and it is available in those same pens. If you leave it on the board, or your soldering iron, it will eat through the copper and pit your tip.

The pen based stuff is a lot less fluid than the bottled stuff. ... For normal SMD stuff the pen is perfect.

I use the bottled stuff but dispensed with:
http://www.all-spec.com/products/FDPENESD.html
or:
http://www.all-spec.com/products/FDBRUSHES.html

I get the control of a pen but I buy my flux in bulk so it's a lot cheaper.

Funny, I would have put it the other way around! :-)

Seriously, brass seems to wear the tip a lot less than a sponge while being more effective at removing excess solder.

I'm not referring to wearing the tip out. Brass is a lot softer than the iron tip and so it should not cause any wear at all. I'm simply referring to the scouring action you get when using brass- with respect to contaminants that is.

A sponge is obviously better for removing chemicals but brass is more suitable if you are just doing one joint after another on a fairly clean board.

I couldn't agree more.

I can work twice as fast when building things with brass because it perfectly removes excess solder every time with no effort where as a sponge requires a bit of work some times. I find that since moving to brass the actual iron and process of soldering is now secondary to building and developing circuits. I just don't have to think too much about it any more.

I use my brass pad about 90% of the time during a normal session. I use the sponge only if I feel the tip has become contaminated with a chemical and then right before I put it away at the end of the session just to remove all remaining flux.
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Re: Choosing a new soldering iron...

by sirket on Sun May 23, 2010 12:21 am

I don't have a picture of my home workbench right now- I'll take one tomorrow if anyone is curious- but this is the soldering station I use:

http://www.action-electronics.com/grc/wewrs7000x.jpg

I also have the Hot plate that goes with it:
http://www.cooperhandtools.com/onlineca ... 00_300.jpg
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Re: Choosing a new soldering iron...

by mojo on Sun May 23, 2010 2:34 pm

sirket wrote:The reason you have them is the one listed on Wikipedia. A fuse in the plug only protects against one additional failure mode- that of a device drawing enough current to melt its wire without tripping the breaker for the outlet. US wiring is different in that our outlets, wall wiring, and plugs are all just generally rated to carry the breaker current. Any more than that and the breaker trips without melting the wire.


There is another reason that you are missing, a very important one. What if the cable gets damaged? Say you are vacuuming up or it gets caught under the wheel of a chair or leg of a table and frayed? In that case you now have a bare wire capable of delivering current up to the limit of the distribution board fuse/breaker.

That said- if there is a catastrophic failure that causes the fuse to trip - then in the US- the breaker would trip.


Keep in mind that breakers are by no means standard in the UK. A lot of buildings, particularly houses, have fuses or even fuse wire. Also keep in mind that the fuse/breaker has to be set to a pretty high value because a single ring main can have multiple 13A devices on it. At 240V that is over 3000W per device. Typically 32A fuses are used in the UK, so more than enough current is available to start a fire or kill you.

New buildings have breakers but still use ring mains. It saves on copper wiring which was in short supply after the war and is now getting more expensive again.

Again- the only thing that a fuse in the plug protects against is when the socket can deliver more current than the wire can handle- and the fault is in the wire itself, before the fuse in the device. That's rare enough, and coupled with the lower currents and larger number of smaller breakers in US houses- it's not a concern.


If that were the case then a table lamp would need a cable capable of carrying 32A or ~7600W since that is the available current on the ring.

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Re: Choosing a new soldering iron...

by mojo on Sun May 23, 2010 2:38 pm

sirket wrote:
mojo wrote:I have done a few of those at work. A little Cillit Bang works wonders but you do have to be careful with it. Otherwise the usual IPA and ultrasonic cleaning works, with an eraser to polish the cleaned contacts. Many a mobile phone or PDA has been revived that way.

I get a lot of boards with copper oxide corrosion and it's a pain to get off with an eraser. an RA flux will clean the pad right up without any effort. It's also useful in cases of lighter corrosion when I don't want to disassemble the project and put it in the ultrasonic bath.


Do you know what Cillit Bang is? It cleans up limescale and oxidisation on copper coins effortlessly.

A sponge is obviously better for removing chemicals but brass is more suitable if you are just doing one joint after another on a fairly clean board.

I couldn't agree more.


You said exactly the opposite in your previous post. Anyway, glad we agree on this.

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Re: Choosing a new soldering iron...

by sirket on Sun May 23, 2010 6:24 pm

mojo wrote:There is another reason that you are missing, a very important one. What if the cable gets damaged? Say you are vacuuming up or it gets caught under the wheel of a chair or leg of a table and frayed? In that case you now have a bare wire capable of delivering current up to the limit of the distribution board fuse/breaker.

If it's a bare wire but not shorted then you're still in danger- a fuse won't help if you grab said wire while grounded. This is what GFCI is for.

Keep in mind that breakers are by no means standard in the UK. A lot of buildings, particularly houses, have fuses or even fuse wire.

Mojo- honestly- it just seems like you enjoy being contrary. I specifically said the US- and the discussion was specifically about why fused plugs are _not_ used in the US.

Also keep in mind that the fuse/breaker has to be set to a pretty high value because a single ring main can have multiple 13A devices on it. At 240V that is over 3000W per device. Typically 32A fuses are used in the UK, so more than enough current is available to start a fire or kill you.

100 ma is enough to stop your heart- the difference between 15 and 30amps is largely irrelevant in terms of starting a fire or killing you- both are perfectly capable of doing it. The difference is in the organization of the systems. I was pointing out why the US doesn't use fused plugs. I have no idea what you're arguing except, perhaps, that the British use a different system- and I've never said otherwise.

New buildings have breakers but still use ring mains. It saves on copper wiring which was in short supply after the war and is now getting more expensive again.

At the cost of:
1. Adding fuses to every plug
2. Needing to use larger wire to carry the ring current in the first place (which can be more difficult to work with)
3. Needing additional wire to supply both sides of the ring which can be more difficult to run if there isn't a convenient second path (running the secondary path next to the first would defeat the purpose of minimizing voltage loss)
4. Complicating maintenance as you must disable the entire ring to work on a single outlet

I'm not saying the system is wrong- it's simply a choice- and one that the US has decided against. It isn't any more or less safe. Just different.

The cost of copper wiring, relative to the cost of a house, is pretty small- even with the higher cost of copper today.

If that were the case then a table lamp would need a cable capable of carrying 32A or ~7600W since that is the available current on the ring.

Again you're talking about the British system and I was _VERY_ clear that I was referring to the US system and WHY we don't worry about such things.

Please read what I wrote:
"In the US we used star topologies with 15 amp breakers. Since most wiring ends up being 14 gauge- there is no need for an additional fuse because the wiring can handle the full current supplied by the breaker."
Last edited by sirket on Sun May 23, 2010 8:10 pm, edited 2 times in total.
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Re: Choosing a new soldering iron...

by sirket on Sun May 23, 2010 6:39 pm

mojo wrote:Do you know what Cillit Bang is? It cleans up limescale and oxidisation on copper coins effortlessly.

I'm not familiar with the brand but I am familiar with the concept. They use ACID to remove oxides- wait for it- JUST LIKE AN RA FLUX. The manufacturer recommends against using it on sensitive metals like copper (http://en.wikipedia.org/wiki/Cillit_Ban ... er_Trigger) because it eats away at them if you leave it on the surface- just like an RA Flux.

So I can either use Cillit Bang, then wash the board, then solder. Or I can solder, then wash the board and save a step.

Also- flux is designed to be used for soldering. Cillit Bang is not. You have no idea what other chemicals might find their way into a batch of the stuff- and you have no idea what such contamination might do to the solder joint.

You said exactly the opposite in your previous post. Anyway, glad we agree on this.

No I didn't- please see:
viewtopic.php?f=44&t=13784&start=15#p78475

Wherein I state:
"Brass wool doesn't drop the temperature and is rough enough to remove stubborn surface contaminants in addition to solder. It's an excellent choice for use when doing a lot of solder joints quickly."

"A sponge will remove chemicals from your tip, in addition to solder and surface contaminants. It can drop the temperature slightly- but it's a better choice when using activated fluxes (i.e. not "no clean" fluxes) and before putting your iron away for a while."
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Re: Choosing a new soldering iron...

by mojo on Sun May 23, 2010 8:20 pm

sirket wrote:
mojo wrote:There is another reason that you are missing, a very important one. What if the cable gets damaged? Say you are vacuuming up or it gets caught under the wheel of a chair or leg of a table and frayed? In that case you now have a bare wire capable of delivering current up to the limit of the distribution board fuse/breaker.

If it's a bare wire but not shorted then you're still in danger- a fuse won't help if you grab said wire while grounded. This is what GFCI is for.


Umm... Yes, it will.

Don't take this the wrong way but do you understand what a fuse is? It is a designed to fail if too much current is drawn through it. In the event of you getting electrocuted it will fail as more than the rated current flows through it (and you).

Surely you must have the wrong end of the stick.

Mojo- honestly- it just seems like you enjoy being contrary. I specifically said the US- and the discussion was specifically about why fused plugs are _not_ used in the US.


I specifically said how it good British plugs with fuses are. You suggested otherwise, I responded with supporting evidence.

Anyway, your argument still does not stand up. If you have an outlet with a single 13A breaker on it and plug a 60W table lamp into it then that is clearly more dangerous than having a 1A fuse and totally unnecessary. That is precisely why British plugs are fitted with the lowest possible rated fuse. They teach children about it in school. It's really, really basic safety.

Fuses react faster to over-current than circuit breakers too.

100 ma is enough to stop your heart- the difference between 15 and 30amps is largely irrelevant in terms of starting a fire or killing you- both are perfectly capable of doing it.


15 amps is higher than the maximum commonly available fuse for a British plug which is 13A. Most appliances use a 3A fuse.

I'm not really sure how to convince you that lower current is safer if it is not already apparent to your understanding of electricity. You might as well say that you can die in a car crash at 1MPH (technically true) and that the difference between crashing at 70MPH and 140MPH is largely irrelevant to survivability which is clearly not the case.

The simple fact of the matter is that you are far less likely to die with a 1A fuse than with a 15A breaker. Fuses are also faster than breakers so you are exposed for a shorter time, increasing your chances.

New buildings have breakers but still use ring mains. It saves on copper wiring which was in short supply after the war and is now getting more expensive again.

At the cost of:
1. Adding fuses to every plug


Fuses are very very cheap and do not use much copper which is the material that there was a shortage of.

2. Needing to use larger wire to carry the ring current in the first place
3. Needing additional wire to supply both sides of the ring, as opposed to single ended systems used in the US


True but it's still a substantial saving in copper. Come on, do you seriously think that the government of the UK would not have bothered to find out if their great copper saving measure actually worked before telling everyone to do it?

4. Complicating maintenance as you must disable the entire ring to work on a single outlet


True, it's a major hassle having to turn off every electrical item in a room before working on an outlet (which I do every day just for fun). It's not like there is any benefit either, other than other appliances being off so that you know the whole ring is even if the socket itself is damaged, but I can't imagine how that could ever be of use to anyone.

It isn't any more or less safe.


It is more safe.

The cost of copper wiring, relative to the cost of a house, is a pittance.


It had nothing to do with cost, it was due to a shortage of copper, as I already said.

Copper water pipes are a better place to start as there is a viable alternative (PEX).


We used lead up until the 70s. It was probably a bad idea in hindsight.

If that were the case then a table lamp would need a cable capable of carrying 32A or ~7600W since that is the available current on the ring.

Again you're talking about the British system and I was _VERY_ clear that I was referring to the US system and WHY we don't worry about such things.

"In the US we used star topologies with 15 amp breakers.


So what level of protection does the very thin and cheap power cable that only provides maximum 60W have? A 15A breaker? Even on the 120V system that is 1800W. Sounds like a brilliant idea having 1800W available to a $5 lamp.

Okay, I give up. If you still can't see it then I won't waste any more time trying to educate you.

PS. To the OP, if you do spend a lot on an iron get one with a fume extractor built into the handle, they are really really worth it.

mojo
 
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