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Taking my MBP on a trip: Old electrical wiring: do I need an adapter or converter?

D

doxavita

macrumors 6502a
Original poster
Jul 6, 2010
614
3
I'm taking my MBP on a trip, the place where I'll be using it has old electrical power outlets (only the two parallel metal blades fit, but lacks the third "grounding")

My MBP's power adapter uses a NEMA 5-15 plug which is plugged to a Belkin Mini-Surge protector I bought http://www.amazon.com/Belkin-Mini-S...YMVO/ref=sr_1_1?ie=UTF8&qid=1305316492&sr=8-1 , this one also has a NEMA 5-15 plug (the standard plug: the two parallel blades sticking out and the grounding pole).

So for such power outlet, what do I need to buy for my MBP's power? An adapter? A converter? Please point me to the appropriate link from Amazon only. Something that won't fry my Power Adapter in case of a surge hehe. ;)

Thanks
 
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You can get a piece for the surge protector that goes in between it and the outlet. It is a ground adapter for two prong outlets. They sell them at hardware stores for around $0.25 to $1 depending on where you are.
It looks like this.
 
mgartner0622 said:
You can get a piece for the surge protector that goes in between it and the outlet. It is a ground adapter for two prong outlets. They sell them at hardware stores for around $0.25 to $1 depending on where you are.
It looks like this.
Click to expand...

Can't see the image. :eek: , but I don't need anything fancy like a converter? a simple adapter will do? (in case of a surge for example)
 
doxavita said:
I'm taking my MBP on a trip, the place where I'll be using it has old electrical power outlets (only the two parallel metal blades fit, but lacks the third "grounding")

My MBP's power adapter uses a NEMA 5-15 plug which is plugged to a Belkin Mini-Surge protector I bought http://www.amazon.com/Belkin-Mini-S...YMVO/ref=sr_1_1?ie=UTF8&qid=1305316492&sr=8-1 , this one also has a NEMA 5-15 plug (the standard plug: the two parallel blades sticking out and the grounding pole).

So for such power outlet, what do I need to buy for my MBP's power? An adapter? A converter? Please point me to the appropriate link from Amazon only. Something that won't fry my Power Adapter in case of a surge hehe. ;)

Thanks
Click to expand...

If I understand it correctly, this question actually has nothing to do with the MBP, right? You are wondering how to use your surge protector in a location without three prong outlets, right?

There are two issues here:
1) even three prong outlets are not necessarily grounded, so a good surge protector will have an led indicator showing whether it is really grounded.
2) you can use a two prong "cheater adapter" to make sure you can still insert the plug on your adaptor into the wall, but the reason they have that led on the surge protector to tell you if it is grounded or not, is because that is the proper way to operate it.

Short of rewiring the outlet, I do not think you can operate the surge protector properly in that environment. I am definitely NOT knowledgable about this subject, and I think you will have better luck asking an electrician or Belkin.
 
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By the way, I use surge protectors at home. But, I do not use surge protectors when I am out (coffee shops, university campuses, or traveling) and I do not use converters when I travel overseas (Asia). I have never had a problem with my electronic devices (knock on wood) and neither have my friends.

That said, it is obviously safer to have a surge protector. It is just a pain to carry around with you all the time. And, in reality, you probably won't have any issues as long as the weather isn't stormy. Lightning is definitely dangerous, and my family has had TVs, telephones, and other electronics destroyed by electrical surges.

But, of course, that has only happened at home, and that is why I have the surge protectors there :)
 
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doxavita said:
So a simple adapter like this is more than enough? http://www.amazon.com/Prong-prong-g...6AUM/ref=sr_1_2?ie=UTF8&qid=1305340826&sr=8-2

I guess if the wall outlet has no "grounding" built in, then there's simply no other way to protect my surge protector and the MBP's power adapter. In case of a surge my mini surge protector will simply sacrifice itself. (the green protected led no longer on)
Click to expand...

One of those is what you need. It's really the only way that I know of to use a 3-prong plug with a 2-prong outlet. My understanding (How Surge Protectors Work) is that a surge protector does not have the ability to protect against surges if the outlet is not grounded. I live in old house that does not have grounded outlets and I use one of those adapters along with a surge protector power strip, although I now know that it's really of no use.
 
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doxavita said:
I'm taking my MBP on a trip, the place where I'll be using it has old electrical power outlets (only the two parallel metal blades fit, but lacks the third "grounding")

My MBP's power adapter uses a NEMA 5-15 plug which is plugged to a Belkin Mini-Surge protector I bought http://www.amazon.com/Belkin-Mini-S...YMVO/ref=sr_1_1?ie=UTF8&qid=1305316492&sr=8-1 , this one also has a NEMA 5-15 plug (the standard plug: the two parallel blades sticking out and the grounding pole).

So for such power outlet, what do I need to buy for my MBP's power? An adapter? A converter? Please point me to the appropriate link from Amazon only. Something that won't fry my Power Adapter in case of a surge hehe. ;)

Thanks
Click to expand...

For my travel charger, I took a pair of pliers and twisted the grounding prong out of the plug. When you use one of those 3 prong to 2 prong adapters, the ground prong is routed to a ground lug, but nobody bothers to connect them to the faceplate screw anyway. At home I have the non butchered charger with the ground prong intact.
 
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Why not just use the standard two-prong connector that comes with the MBP power adapter?

You get a shorter cable but then no need to buy an adapter, and as said above I don't know if the surge protector will really do much good without a grounded outlet.
 
The fact that MBPs already come with a 2 prong adapter, does that mean Apple isn't really concerned about surges to the Power Adapter?
 
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doxavita said:
Right, it's missing a grounding pole. If a surge came the white box would be fried.
Click to expand...

More likely you would get shocked. That grounding pole doesn't really provide protection for the power supply or the machine.

Buy yourself a surge protector and plug the computer into that.
 
If you were ultra concerned about this problem and the possibility of unsafe power, storms or anything of the sort , you could use the ground lift adapter(3 prong to 2 prong) and run a thin gauge wire on the ground lifts tab to a cold water pipe in the house.....
 
anshu said:
If you were ultra concerned about this problem and the possibility of unsafe power, storms or anything of the sort , you could use the ground lift adapter(3 prong to 2 prong) and run a thin gauge wire on the ground lifts tab to a cold water pipe in the house.....
Click to expand...

Hmm, I don't know what could be the result of doing that :D
 
doxavita said:
The fact that MBPs already come with a 2 prong adapter, does that mean Apple isn't really concerned about surges to the Power Adapter?
Click to expand...

The 3rd prong has nothing to do with surges. It's normally a ground for the chassis in case the regular return AC line isn't working properly, in which case you'd be the ground and get fried. Since the power adapter only has 2 pins, you're not getting the benefit of an alternate ground pin anyway so don't worry about it. Just get whatever you need to make the plug fit like a $1 extension cord from Walmart.
 
OK, so as I understand, my best bet is to use that simple 3 prong to 2 prong adapter (which I already bought) and plug my Belkin Mini Surge Protector to that. That's pretty much the only way to use my MBP with old power outlets.
I most likely won't be able to set up grounding for that, so I hope I won't get shocked. If a surge came, I don't know where that fluctuation would be sent to, (perhaps my mini surge would take care of that?) Would that be hazardous?
 
doxavita said:
OK, so as I understand, my best bet is to use that simple 3 prong to 2 prong adapter (which I already bought) and plug my Belkin Mini Surge Protector to that. That's pretty much the only way to use my MBP with old power outlets.
I most likely won't be able to set up grounding for that, so I hope I won't get shocked. If a surge came, I don't know where that fluctuation would be sent to, (perhaps my mini surge would take care of that?) Would that be hazardous?
Click to expand...

Without the 3rd prong there will not be a ground so theoretically you could get shocked. Without the 3rd prong the surge protector will not be able to divert the surge to the ground (the same as if you didn't have a surge protector) and theoretically your equipment could be damaged by a surge.
 
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