Surge Protection

Dont forget to unplug the telephone cable too in a big storm

just to be on the safe side!!

Just bought an UPS from the same store where I bought the computer stuff about a week ago. You would think that they would have tried to sell me that when I bought the other stuff last week. Anyway, it is surge protector followed by a voltage stabilizer and a battery in parallel. Cost B2,350; there was one cheaper at B1,850.
I could not find any Joules rating, neither could I see the the 'protector' to know its size.
The salesman said that I should turn it off when I would be away from home. I don't get that; is it for the possibility of lightening or there are some other reasons for turning it off.
Also, bought a power strip from HomePro; but once again there is no Joules rating or anything visible other than the sockets.

Ray.Charles wrote:Just bought an UPS from the same store where I bought the computer stuff about a week ago.

Which store was that?

(Sorry if it was mentioned in this thread - too lazy this morning)

Maybe they don't post the joule rating in Thailand they do in the US its right on the package and also stamped on the bottom where they have the product specs. Rule of thumb on the joules is the higher the better. It sounds like you got a good one though as only the higher end UPS has the voltage stabilizer.

I bought all of my HP stuff from
BD Computers
121/11 CHICHOMPCHUN
Tel: 042 329130
It is a very large store; couple of young guys there somewhat know what they are talking about.

Hi,
Looking for protection devices some time ago, in LOS, all i could find was mains socket devices. The one i had back home was a Belkin, bought through Farnell, it had 8 socket outlets and a protected telephone line Incorporated in it. Just plug tel. line into it then o/p to Comp. This came with a lifetime warranty and Belkin would pay for any equipment connected to it that was damaged by surges or lighting. I had a direct lighting strike on my house while using computer, no warning, just one bolt of lighting that night and no thunder before.
The protection device worked fine but was damaged, did not open it as i had to send back to Belkin. Sent it back to Belkin and they replaced it free of charge, even asked me if i had any equipment damaged. All my equip. i had connected to it worked fine. The shock to me seeing the whole room light was the only bad thing. The device four years ago cost me 40GBP. plus VAT.
One thing though you need a decent earth as it will not work correctly without a earth. Says so in the papers i got with it, the cost varies depending on what rating you want protection for.
Will be getting another one when i go home later this year.
Cheers Doug.

My house has 3-pin sockets, but I haven't yet found out how are they grounded. In the States, the codes require GFI (ground fault intercptor) sockets at locations exposed to water, e.g deck, garage, as well as at interior points like bathroom and kitchen. I wonder if they are available in Thailand.
By the way, perhaps an easier solution is to install a lightening arrester on the roof.

GFI's are available in Thailand. Global has a good selection. I asked an electrician to install a GFI in my house, but after he went into the attic and saw the method and condition of the wiring, he said that he would have to completely re-wire the house in order for the GFI to work properly. Apparently, the electrician who installed the wiring took shortcuts, such as connecting some outlets to the neutral before the neutral gets to the electrical box. To that, add lots of uninsulated splices laying on (conductive) concrete, and there would probably be too much leakage. You can ask a qualified electrician to have a look at your house.

By the way, some guys were going door-to-door here, selling GFIs several months ago. They wanted about 8,000 baht for a small one. Comparable GFIs at Global cost about 3500 Baht or less, and the installation certainly be inexpensive. I would not recommend buying anything like this from door-to-door types.

I have made some GFI boxes for outdoor use - mainly on the lawn mower and the washing machine. They have male and female three pronged plugs so its kind of like a small extension cord with a GFIC breaker in the middle.

That is what I was afraid of. Having 3-pin outlets only implies but does not guarantee good grounding.
I wonder if the GFIs are voltage dependent. In the States, they will be less than $10 each.

I want to echo what lighspur1 said about grounding ... the main electrical cause of failure of sensitive (low voltage) equipment in Thailand is not power surges or fluctuations, it's charge building up on non-grounded (non-earthed) power. If you're using a 2-pin socket, your stuff isn't safe, even with varistors in the way.

Domestic UPS units often only offer failover service, which means they only kick in when there's no mains power. This means such devices offer no protection against surges. If you want UPS consider whether it is for isolation or continued service. It's unlikely to provide the former.

It's also worth noting that a lot of "surge protecting" extension cords only protect the "live" and not the "neutral", which is pretty pointless. If you get a lightning strike it's not going to carefully choose one particular wire and not the other.

Read this: http://www.thailandguru.com/grounding-e ... rical.html (I have nothing to do with this people, and cannot comment on their services. But their advice is good.)

A.

I bought a 2,350 baht UPS about 2 years back, supposedly with surge protector and voltage stabilizer. Now, not only the power supply is not uninterrupted under a power outage, the ‘UPS’ cuts off power to the computer 2-3 times a day when there is no power outage. I am beginning think that there is a joker ghost inside the box.
Anyway, I have now decided that I could do without an uninterrupted power supply; my computer usage is mostly reading forums and e-mails and sending short e-mails. Longer e-mails I write off-line and if the power goes away, Mr. Gates will save my work.
What I really need is something that will protect my computer and accessories, especially the hard disc, from a surge. I saw some power strips that claimed to have surge protection, but as best as I could determine they had fuse or a circuit breaker inside. But, with my new-found knowledge, I will have nothing less than a Metal Oxide Varistor to protect my computer. I checked at Home-Pro, but the specifications were sufficiently vague to confuse me about their capabilities. Please advise.
Another thing I do not understand is why in this country of frequent and severe sparks in the sky, the houses do not have lightening arrestors. Comments please.

Your UPS must be earthed to do its job properly.

...and to a proper earth - 1.5m copper rod in the ground.

Ray

Why don't you check the outlets yourself. All you need is a simple test light which can be made froma 220V incadescent light bulb and 2 wires. Solder 1 wire to the side of the bulb along the threads and the other to the base (center). The wire attached to the base will be your hot (+) lead and the one on the side your neutral (-)/ground lead. I would use electrical tape to seal everything to avoid a shock. Plug the + wire into the narrow blade opening of your outlet and the other wire into the ground opening. If you have a good ground your light bulb will light. No light no ground.

Maybe the best was is to get one of those 300 to 400 baht digital voltmeters. Failing that, there is a safer form of a similar tester. Just get one of those "AC Indicating Screwdrivers" sold in the hardware stores. Inside is a neon bulb and a high value (many meg ohms or more) high voltage resistor. You can run a wire from the metal pocket clip to and use the wire for your neutral/ground probe and the tip for hot. A little electrical tape as above to cover the ground/neutral connection to the metal clip (because you won't really know whether you are testing Neutral, Ground, or Line until you test it!) will help improve safety.

When testing and measuring AC line potentials, keep on hand in your back pocket to minimize the chances of accidental electrocution.

But back to the earlier question; I too have wondered why lightning rods are used in Europe and the Americans but rarely in Thailand. Is it because buildings tend to no't burn here if struck by lightning? Inquiring minds want to know!

As far as telling which surge arresters actually work, you really won't know until you test it, with real surges. The best you can hope for is to buy a respected brand and hope its not a fake. Additional confidence can be had by opening it up and looking for surge suppressors such as MOVs inside. Maybe there are some other tips, such as recommendations for specific brands and models (let's hope).

Rick
Excellent idea using the small screwdriver tester with a wire attached to the pocket clip to check for ground. Much better than my suggestion using a light bulb.

I think the problem with using lightning rods on buildings is that they are unreliable. I come from Florida which has been called the lightning capital of the US and most structures there do not use them either for this very reason. This may have something to do with the amount of electricity contained in a lightning bolt and its ability to jump from one point to another. Thailand seems to have very lightning strikes by comparison. I believe a bigger concern is electrical surges coming through the lines due to faulty power equipment. A good surge suppressor (ie Belkin or ???) used on a piece of equipment should be able to offer decent protection.