What Purpose Does a UPS Serve When There Are No Grounded Outlets Around?

I'm on vacation for a long while in a foreign country where there are regular brown outs occurring. And well I don't trust the power in this country much so I bought a 500VA UPS (Forza brand). It's got battery protection for up to 12 mins or so the box says. Also has surge protection and I would assume the battery protection helps for brown outs too. Now my question is what purpose would using this UPS serve if the wall outlets here aren't grounded? Because none off them are. And I've got a MacBook Pro I really can't afford to fry or lose, since I'm still paying the dang thing off. Also being that's it's a laptop (that obviously has a battery itself), should I expect some self protection on it's own accord? I'm not sure if brown outs are surge related or dips below that come back and never pass a surge level. But I need as much info as possible before I setup this thing and connect my MacBook Pro to it. The UPS itself has a three prong cord like anyone in the world would. But I'll have to use a three to two prong wall adapter for it to work here since none of the outlets are grounded, even physically speaking the plastic covers for the outlets here only have two flat insert holes for each plug (eg: hot and neutral). Please give me some insight as to whether I should be worried about using it or not. My MacBook Pro's been in my drawer with 0% battery power since I got here 12 days ago. And for those of you wondering, nope the UPS won't sound an alarm if the outlet it's connected to isn't grounded. Most people in this country use two to three prong adapters for any cord that comes with grounding. I guess I'm more so wondering if surges can occur on a countries power grid without the occurrence of lightening storms. I would obviously unplug the UPS from the wall as well as my laptop of I heard a storm. What functions would this UPS serve me without grounding it? Should I be concerned?


http://static.mercadoshops.com/ups-forza-nt501-500va-tomas-regulador-supresor-de-picos_iZ114XvZxXpZ6XfZ143681471-416887394-6.jpgXsZ143681471xIM.jpg


http://mec-s2-p.mlstatic.com/ups-marca-forza-modelo-nt-501-con-2-anos-de-garantia-16385-MEC20118696563_062014-F.jpg


Thanks in advance

 

A UPS works with or without an earth as it supplies voltage between active and neutral. The earth is only for user protection but these days most electrical consumer goods are double insulated and don't need an earth at all. In many countries the power connection system is MEN (multiple earth neutral) and in this system the earth is connected to the neutral bar inside the switchboard and an earthed mat (buried metal mesh) is connected to the neutral at the utility company transformer on the power pole.
Another common earthing connection system is direct earthing and the neutral is not connected to the earth connection at all and in these systems not only can you get a shock off the active but if the power company hasn't balanced its three phase load properly between all users then you can also get a belt off the neutral wire. Generally with the MEN system (unless faulty) you can't get a shock off the neutral as it is at earth potential so to make a device safe the isolation switch only has to turn off the active so single pole switches can be used which is cheaper
There are many other systems with differing names and this is not really the place to discuss but suffice to say all are loosely based on these two earthing systems and the differences relate to where the earth stakes are or are not connected :cool

 

I'm no electrician, but if no grounding is going to the batteries, and the batteries themselves are powering the computer, does grounding even matter? :confused

 

For the sake of some possibly better answers I took the liberty of taking the cover off the electrical panel here. Took some pics and hope they help give a more concrete answer. Remember all of the outlets in every room here do not have the third ground plug hole. The slots that are there are the same as you'd find in Canada or America, just no third ground hole on the outlets. So anyways here's a look at the wiring in the panel. I see a green wire going to a small area where a lot of other wires are connected to. I'm also no electrician but does that mean that somehow all the outlets are grounded as per Joffa's post of other possible grounding methods? Hope you guys can give me some insight as to what you think about the wiring and if it looks like things are actually grounded here nonetheless.


Thank You


http://i.imgur.com/9y3QEi5l.jpg

http://i.imgur.com/Blo6Mpdl.jpg

http://i.imgur.com/5ZIcM0Ml.jpg

http://i.imgur.com/SJr66EIl.jpg

http://i.imgur.com/euqfaZel.jpg

 

What joffa said is correct. And what theefool said also has a lot of credit.



Here you see that the blue lines that I drew are your neutral bars and the reddish brown line is the bar that ties both neutral bars together, so if it is to be believed that the green wire is the earth, coming up from the earthing rod, then that entire circuit is connected to earth, or grounded if you like.

I would also like to point out that as theefool also pointed out above, if this is all for a laptop, having an earth connection is of no consequence. In fact a UPS is overkill, a surge strip would have done fine. The laptop's battery would give backup power, and the surge strip protects against surges, spikes and noise, if you get a good one. The UPS will cover all these functions, plus provide redundant backup power in case of power outage, or voltage drops.

I would also like to point out that all the laptops that I know, including the Macbook Pro, only has 2 prongs on their plugs, so they wouldn't make use of an earth or 3 pronged outlet anyway.

 

As a qualified electrician I can say from the photos you have no worries. The neutral (white) and earth ground (green) are bonded. This means that any current will take the path of least resistance, be it the neutral tap of the transformer or the grounding rod.

Most any piece of equipment sold these days is double insulated, or in simplest terms the chassis of the equipment is bonded to the neutral. This negates the need for a separate earth ground as any short circuit current will flow to the neutral.

Fair warning however, if you do have a three prong piece of equipment NEVER disable the ground pin of the plug. This can and has led to the chassis of equipment becoming energized, and when one does touch the chassis you become the path to ground. Fatalities due to such disabling of protective features have, and do occur.

As far as your laptop, it should last far longer than 12 minutes on the UPS...

 

Would the battery function still work on this UPS if I used it in my place back home after leaving from my trip? I ask because we do have three prong outlets back home (North America), but there is no grounding in the third prong at all since it's an old home. I would assume the battery backup function would still work, but that it wouldn't be useful at all for surges. Like I said this UPS does not have an alarm if there is "no grounding present." I wonder if using it back home without grounding in the third prong (even though the faceplates have three holes on the wall), could cause damage to the UPS or my laptop/anything plugged into the UPS?

Thanks again

 

When you get home, you simply purchase a three prong adapter. You will need to remove the cover plate screw, plug in the adapter, and then reinstall the screw through the provided green tab.

 

@themekanic

I've actually heard of this method before using an adapter... But have never heard of any solid explanation as to how it helps exactly. The best I've read long ago says it sends a surge to the box via the newly screwed tab on the adapter. But if that's the case where does the surge really go to and what positive affect does it have if it just ends there in the outlet?

It makes me wonder if a surge would really just travel back and ruin the connected device(s). It sucks because the home is well in it's age and there will be no electrical work done there to correct the grounding issues in a real way anytime soon. But if it really does work I'd start doing it in various outlets.

Is it safe to do so with a surge bar/strip too?

 

What you need to understand is the basics of grounding, and bonding. (NEC Article 250)

When you install a duplex outlet in a wall there is a green hex screw on it. That screw is where the bare copper is to be attached, which is the ground wire. Any Romex wire will have a bare conductor. The green screw is there regardless of it being a two prong, or three prong outlet. All the wiring in the house is routed to the panel. Inside the panel the white wires are attached to the neutral bus, and the bare wires are attached to the ground bus. By code, the neutral and ground bus MUST be bonded inside the panel, NO EXCEPTIONS in a typical residential home. In simplest terms, it means they are connected to each other.

As long as the outlet is properly grounded, and the busses in the panel are bonded any overcurrent which flows to that green screw or tab will take the path of least resistance. This means it will flow either to the ground rod outside of the house, or to the neutral tap on the transformer. Additionally, the ground and neutral inside of the UPS are bonded together as well, the only exception being if said UPS is designed to have an isolated ground.

The other exception is if the outlet is not wired properly, then of course current will not flow through the bare wire if it's not connected. There would be no difference in potential if such was the case.

As long as the nut twister did his or her job right, there will be no issues. Any device is permitted to use such an adapter.