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Power protection for the international traveler
A multi-outlet surge protector that works in 150 countries
coopster




msg:4087840
 2:23 pm on Feb 26, 2010 (gmt 0)

I once carried around a multiple adapter and surge protector system. However, my last trip brought about new issues so I decided to ditch my old ways and do a little research today. I came across this little gem ...

[monstercable.com...]

Multiple outlets, USB ports and an adapter that works in 150 countries. Nice. I submitted a pre-sales request to find out more about surge protection. I notice a fuse in the adapter but I don't want to assume that it means it is surge-protected. I blew the fuse on the last outing, which reminds me -- make sure you carry extra fuses. In some countries/places it is impossible to get a new fuse!

 

Leosghost




msg:4087847
 2:43 pm on Feb 26, 2010 (gmt 0)

The list of the purported 150 countries would be nice ..because from what I can see from the photos it wont work in France ..our plugs have cylindrical ( round prongs) either 2 or 3 ..and thus our sockets ( wall outlets ) have round holes either 2 or 3 .. and the adapter doesn't show the "male" end ..because the male end on the plug shown definitely wont fit anything here ..

edit ..just allowed scripts in order to see if there were other images ( amazing how many sites think they need scripts to show thumbnails !) ..So looking at the pictures of the male end of the adapter ( image is 3 rd from left )..Sorry Coopster ..it wont fit France ..in fact it looks like it will only go into British wall outlets ..and if those slide things mean that it has prongs that slide in and out ..none of the holes are in the correct shape or places to slide out round prongs for our sockets ..

coopster




msg:4087978
 6:38 pm on Feb 26, 2010 (gmt 0)

Actually, you are only seeing one side of that adapter. It is a complex little piece of equipment. Have a look at the Amazon photo gallery too, some better angles on the adapter itself:

[amazon.com...]

I discussed surge protection with the manufacturer this morning. This particular unit does NOT have surge protection. The 4 and 6 outlet models in this product line do though. It is their "Outlet To Go" product line. The Worldwide (W) version does not have surge protection or a circuit breaker so keep that under consideration. That means I'll still have to carry an additional travel surge protector. I was hoping to rid myself of that piece. Oh well.

Leosghost




msg:4088009
 7:10 pm on Feb 26, 2010 (gmt 0)

took a look at the amazon pics ..( same views as the manufactures though ) female side ..and male side with UK pins extended ..still don't think it will work here ..even if you extend what look like the round pins ( towards the top of the male side image )..the sockets ( outlets ) here are nowadays themselves "inset" into the walls ( at least in the places that conform to the fire and electrical regulations ..like hotels etc ) by 3 cms ..So as to prevent you wrapping your fingers around the plug , touching the prongs and getting a shock that way ..Would have worked in some of the older places that I have lived in here though and in the rooms in this house that I haven't yet rewired according to "code" ..

kaled




msg:4088227
 2:12 am on Feb 27, 2010 (gmt 0)

Surge-protection is a good little money-maker but is rarely worth the money.

Modern switch-mode power supplies include voltage regulation over a wide input range. Most devices that do not include such power supplies (such as rechargeable toothbrushes) are not critically sensitive to input voltage.

Kaled.

Visit Thailand




msg:4088235
 2:26 am on Feb 27, 2010 (gmt 0)

This [powerbuy.co.th ] fits every plug I have ever needed and it is made by Belkin and comes in numerous sizes with different surge protection.

lammert




msg:4088830
 9:33 am on Feb 28, 2010 (gmt 0)

After having blown up some computer equipment using commercial surge protectors I now build them myself. In the area where I commonly travel the main problem which occurs is that after a repair on a central transformer wires are changed and 220V becomes 380V on some outlets. Most commercially available surge protectors don't shut off if you supply them with 380V, but it will fry your electronics within moments.

My ultra sensitive home-brewn protectors will switch of directly if this kind of voltage is detected and I haven't had any damage anymore since I use them.

Total costs about $2 in electronics parts.

kaled




msg:4088865
 11:52 am on Feb 28, 2010 (gmt 0)

Are you sure about those 380 volt surges? In order to achieve that, one of three live outputs would have to be confused with a neutral - I don't imagine this happens very often. Also, whilst some equipment would survive, every filament light bulb that was switched on would blow immediately.

Over the years, I've heard many stories of wires getting crossed to produce a higher voltage, but I'm not aware of any such story that stands up to scrutiny.

Kaled.

lammert




msg:4088878
 1:36 pm on Feb 28, 2010 (gmt 0)

Yes, these are 380V surges.

I am talking about older electricity nets in a former Soviet country. After the communism fell many wires and equipment were stolen or sold and temporarily replaced with just what they could find just to keep electricity flowing to the houses. Those transformer houses are really a mess inside. It is easy to confuse a neutral with a live line in there and it happens about once every six months.

coopster




msg:4089548
 10:42 pm on Mar 1, 2010 (gmt 0)

Can you describe the components and assembly?

lammert




msg:4089726
 5:02 am on Mar 2, 2010 (gmt 0)

The two main components in my home-made surge protectors are a varistor and a fast fuse of about 1A.

A varistor [en.wikipedia.org] is a coin shaped component which is also often present in commercial surge protectors. The varistor is connected between the life and neutral lines. If the voltage difference between these two lines stays below a certain threshold, the varistor works like an isolator. Once the voltage comes above the level, the varistor starts to conduct and creates a shortcut between the neutral and life line.

There are a few differences between my setup and commercial protectors.
  • First of all I have chosen the varistor with the lowest breakdown voltage usable in my situation. With 233VAC on the net (our maximum here) you get about 330V peak voltage. I have chosen the first higher available varistor. In commercial surge protectors you often see a varistor which is one or two steps higher in breakdown voltage because they have to function all over the world.
  • Second I have chosen the varistor with the highest allowed surge current. Varistors have some internal resistance and with a shortcut between the line and neutral, you easily create currents in excess of 1000A. If you look at the V/I graphs of varistors you will see that this can increase the voltage to 100V or more above the breakdown voltage. Enough to damage your equipment. High current varistors are larger and more expensive, but that is all relative. I pay about $1.50 for each which is much for such a component, but just a fraction of repair costs for the attached hardware.
  • In commercial surge protectors you will often see some coils which limit the surge currents. These coils are there to protect the surge protector, not your equipment. The coils limit the maximum current through the varistor, extending the life of the varistor. This is fine with a short peak on the line, but with sustained high voltages this is useless. I therefore use a fast 1A fuse instead in the life line between the varistor and the wall outlet.

With this setup a high voltage peak causes the varistor to short circuit the line and neutral. The high current blows the fuse within moments and the computer equipment either shuts of, or continues on battery power (laptop).

The fuse is mandatory because a varistor may cause fire if it is overloaded too long. The whole setup should be in a closed housing. I had one varistor exploding during such an event. Attached equipment was fine though. When a fuse blows, I also always replace the varistor, because it may be damaged internally and not function correctly the next time over voltage occurs.

graeme_p




msg:4091301
 9:54 am on Mar 4, 2010 (gmt 0)

Modern switch-mode power supplies include voltage regulation over a wide input range.


I have had two PCs go bang and start pouring out smoke in Sri Lanka - and there are plenty of countries with still worse infrastructure.

Over the years, I've heard many stories of wires getting crossed to produce a higher voltage, but I'm not aware of any such story that stands up to scrutiny.


It happened to me. Our entire road had a surge that caused a huge amount of damager - we got off lightly with one air-conditioner needing a cheap repair, one very old PC, surge protectors and a UPS written off. A lot of people ha TVs or fridges damaged The apparent cause was a falling branch pushing two cables together.

Most commercially available surge protectors don't shut off if you supply them with 380V, but it will fry your electronics within moments.


I am glad to say ours did, including the surge protector built into a UPS, several surge protectors and the UPS were write-offs.

kaled




msg:4091339
 12:13 pm on Mar 4, 2010 (gmt 0)

The apparent cause was a falling branch pushing two cables together.
This is precisely why I say such reports don't stand up to scrutiny - such an occurence could not cause a three-phase surge (which would require the neutral to be substituted by another live phase). If a live power cable touches a neutral cable, a circuit breaker will activate immediately (to protect the local transformer). In order for a power surge to result, the short circuit would have to both cut through the neutral cable and connect the live to the far side of the neutral cable faster than the circuit breaker could react but slower than about 20ms.

A few years ago, an underground cable shorted and exploded in the road about 30 metres from my sisters house. The only device that died was the PC (switched off at the time) which, coincidentally, was the only device in the whole house plugged into a surge protector. The cause was most likely a high frequency voltage spike (i.e. very short duration) against which no surge protector will work. To protect from this sort of problem, a low pass (inductive) filter is required. I believe that in some countries, these are actually illegal since they can disrupt power meters! A radio-frequency filter might work (as sold for hi-fi equipment).

Kaled.

graeme_p




msg:4091928
 6:08 am on Mar 5, 2010 (gmt 0)

This is precisely why I say such reports don't stand up to scrutiny

So what happened to us? The surge protectors worked, lights blew, fans rotated noticeably faster (and were the only things switched on that survived), the problem lasted for some time (it started while we were out, when I got back about an hour later I assumed the surge must be over and plugged a PC directly into the mains, then it went bang and white smoke poured out of it).

Why can the neutral not have been touched by another live phase? there are at least three phases being supplied here.

kaled




msg:4092000
 10:18 am on Mar 5, 2010 (gmt 0)

Why can the neutral not have been touched by another live phase?

If that's all that happened, circuit breakers would have tripped immediately. If that didn't occur, the local transformer would have caught fire and/or exploded. I cannot comment on what caused your power surge but I can say with 100% confidence that it wasn't caused by a tree branch forcing two wires together. That may have been the BS line your power company fed you, but it was still BS.

Kaled.

lammert




msg:4092005
 10:57 am on Mar 5, 2010 (gmt 0)

I cannot comment on what caused your power surge but I can say with 100% confidence that it wasn't caused by a tree branch forcing two wires together.

Shortcuts by tree branches falling on the wires in the street or by wind are actually quite common in the street where I live. Due to the line resistance and type of circuit breaker used here it takes on average 3 to 6 seconds before the central circuit breaker near the transformer switches off. Fast enough to protect the transformer against fire, but long enough to see some nice fireworks in the street. I haven't seen much damage to electronic equipment though through this kind of shortcut because due to the resistance of the lines the voltages generally drop, instead of increase.

The only thing which would cause sudden rises of voltage on lines during such an event is when the branch hits the neutral and breaks it, which causes the neutral to float in the direction of one of the phases. But even in that situation you still can't get the full 3-phase voltage in your house. That only happens when as kaled explained two things happen at once, i.e. a cut of the neutral, and at the same time a connection between a phase and the loose neutral line. That won't happen by accident but in my experience is always caused by humans connecting the wrong wires together (which as already indicated happens a few times per year with us).

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