Call an electrician pronto. It may be the power-strip, or it may be that the voltage in the apartment (or even just on that outlet!) is spiking. If things aren't blowing up elsewhere in the apartment, definitely replace the power-strip and plug in something cheap and replaceable (cordless phone, aftermarket cellphone charger, etc).

But it's not uncommon for voltage to run quite far above where it should be. I've seen observed instances of 135 volts here in the US when it should be 110. If something else is on that circuit, it may also be causing voltage spikes that can go WAY beyond 240 volts. I must say, the only time I've ever smoked anything in that manner was not checking a charger (Nikon battery charger) that turned out to only be 120v. POOF! Turns out they made two models. One is dual, one ain't. I bought the cheaper one as a spare and left the dual voltage at home. Oops! Now I always ALWAYS look before I plug something in.

Most likely made in China for a German company. Heap Chinese made power bars are available all over the world. Most of them work just fine. A little more than once a in a while you get a bad one.

Similar problem here in Thailand, with the 220v supply running anywhere from 160v to 240v+! Add a noisy signal to the equation and computer components suffer greatly. I've now got Automatic Voltage Regulators (AVRs) on all sockets which supply my PCs and satellite boxes which do a good job of filtering the supply, as well as boosting or stopping-down the voltage so I get a nice clean 220v. Oh, and that's then fed through a UPS because of the daily black-outs during the rainy season!

I blew up my wife's computer power supply here in Germany by forgetting to switch it to 220v. But then I blew up a German power strip that wasn't even on, and then two German irons that are made here. Turns out the apartment we were renting was running hot.

Now I'm afraid to blow up my meter in my new place or plug anything in...

How do I check the polarity of the 220v-to-110v transformers and my 110v appliances that aren't labeled, in order to ensure I don't blow up anything else? Also, does anyone recommend one of these over the other?

1. Using a 220v setting on a dual voltage appliance, like a desktop PC, with an adapter for the German 220vwall socket;
2. Using a 110v setting, plugged into a transformer.

It's a question of which thing you want to do the work of voltage reduction.

Without question, I'd choose option #1.

I just plugged my Kill-A-Watt into the outlet here in Chicago. I'm currently getting 122.5 volts.

Though I think the US nominal voltage is 120 V.

http://www.kropla.com/electric2.htm

If I recall correctly, nominal voltage in the US is listed as 120V +/- 10%. This accounts to normal swings in grid power. Note this is supply to your meter. After voltage drop on heavily loaded circuits to the end receptical, you could be looking at even lower.

We had a misbehaving power transformer feeding our house when we moved in. It took some convincing but the power company finally replaced it (and upsized it as it was near capacity anyway). I'd start with the power company and complain. It sounds like you've either got a high voltage condition, or perhaps frequent spikes.

As others have pointed out, you can install a line conditioner (essentially an active heavy duty transformer) which will stabilize the voltage, pulling up brownouts and pushing down spikes. These are often used in conjunction with a UPS, or as a combination unit. APC sells both types of units.

Both are wrong. It used to be 220V in most of mainland Europe and 240V in the UK (and presumably Ireland) but in line with EU harmonisation policies we're all now officially 230V, but with a +/-10% tolerance so nobody actually had to change anything.