With an normall multimeter you normally can't check if it is safe.
What you can check is if the voltage is as expected, but normally transformers for computers etc have good margin, so they will be safe.
What you want to check for, is suddden drops, or spikes in the voltage, and an digital meter cannot show you that good enough. And old analog meter will show it better, but you should be on the safe side, and get yourself an surge protector, or an small cheap ups solution. but yes, I know, you are travelling, and should not carry huge batteries..
HI Mr Andy,
If you still in area with many university students, sounds like adults trying to maybe put a lid on how many toys can be used...hehe. Maybe they are limiting kilowatt hours used in a similar fashion to RV parks in USA. They might even go so far as to wire the entire room (light switches, a/c, all sockets) to one leg of hot wire. If the light dims with everything on..certainly not a good sign. The a/c compressor continually cycling on and off also not a good sign of stable voltage of course. There is also the possibility that you have proper voltage but are missing the third leg, ground wire. Dont believe a multimeter could detect that right off the bat. In that situation surges in the voltage being hit and miss only when lightning or everyone turning on a/c for instance. After seeing your pics of wiring spaghetti in some places, I would bet a missing ground wire being the biggest culprit. Especially since Ground Fault Circuit Interrupter (GFCI) dont exactly seem to be in voque. Im in somewhat the same pickle right now in my U-haul conversion.
Try to see if you can get a Residual Current Device (Wiki). We use these in britain to protect certain equipment. It will automatically break the circuit if it detects irregularities in the current, which protects your equipment and saves the hassle of changing the fuse (all UK appliances have a fuse inside the plug as another line of defence).
I believe, I am not sure, that other countries do not put fuses in the plug of devices.
This RCD will only protect from these kinds of problems, however. They are cheap (<£10 UK and I suspect cheaper in most countries if availible) and light weight.
NOTE: I am not an electrician!
I was in Nigeria in a hotel, they where running a genset. Normally I could use an old laptop with damaged accu by using netpower. For some days the engineer was ill and his assistant had to run the gens. They got it wrong: The frequency was out of spec. (to high) Result: The AC sopped hammering, and the bulbs where bright for burning. And the PC did not work at all. Thats not a case for Multimeter, they cannot check that.
By the way: I am a user of Opera browser and very unhappy, that I have to use this Microsoft one for seeing the verification here. Thats the same disturbing like wrong electricity.
God bless you on your travels.
I am not in love with a Mult-Meter, I want a video that show me how to go step by step to guarantee te electricity is safe. I do not care if it used a normal, abnormal multimeter. I want to learn how to check the electricity in any way possible to see if it is in acceptable tolerance levels or danger to my computer.
BUY a USA made Surge Protector. Buy is the USA. Keep your receipt most of these surge protectors guarantee the equipment they are hooked up to for $5,000-50,000 bucks return damaged equipment on return trips. NOTE the reason why they make this guarantee is the surge protector will in 99.998 % of the cases it protect.
Just saying. and if you do become a master voltage meter reader you'll still need a surge protector. Very surprised you don't own a small portable one.
Ash, this ground fault circuit interrupter is a great idea. I could get a Muli-meter to check if the current fluctuates, then put one of these ground fault circuit interrupters inline on my electrical card. Maybe it can work together with a very small surge protector.
The ups thing is not feasible.
most of the UK circuit breakers are a plug with a socket in it (similar to a shape-change adapter for travel) so that you can simply put it between the hotel socket and the plug of your appliance or extension chord.
This means you don't have to worry about wiring it up, and it can be used to protect any of your toys. However, if you wired it into your extension chord/ multi-socket block then I suppose it has the same usefulness, and possibly slightly smaller...
The normal and constant problem is I am in countries where they do no sell these products in an easy to find way.
GO to MBK 5th floor surge protector city.
I suppose I should know what MBK is?
Surge protectors are easy enough, I also want the ground fault detector, this may be difficult to find, however I have yet to look.
Plus the low quality of products in Thailand is the concern.
A ground fault detector is more to protect people than equipment. A surge protector will protect you from some spikes etc. Don't think it would work if the power was just weird (out of sync, etc.) and would probably do nothing if for some strange reason the power was from a square wave inverter or other strange power source.
A multimeter will tell you little, and will tell you only an instantaineous state. There are devices out there that would show you the wave form and all, but they are big and very expensive and hard to find. Stick with protection. If you are going to cary a multimeter anyway, there are a few things you can check, such as voltage, DC voltage (sometimes happens on ac lines) and quality of ground. Won't help much.
A UPS would probably be the only way to go. Since you say that that is not possible, an awkward solution would be to use 12v cords for your computer and phone, get a small 12v battery, and hook it up to a small 12v charger. This is sort of a home made UPS. Stay away from inverters since that would add complications, bulk, unavailability, expense and you would have to get a true sine wave inverter (big $)
It is my opinion that ALL devices that run on batteries should also be able to run on straight 10 to 16 VDC input. Heck, all lower power devices should run on this.
This is MBK:
huge gigantic shop, I guess you know it already.. :)