Tuesday, September 15, 2009

Clock Runs Slow (and other electrical issues)

We knew that European household electrical current was different than US. There are two basic issues you have to deal with: 1) different plugs 2) different voltage (220 in Europe, 110 in US).

Most appliances function under both voltages so all that is needed is a plug adapter. For those appliances that only work with US voltage, you need a converter. As I discussed in an earlier post, I made the mistake with my electric beard trimmer of assuming it was switchable. It was not and I fried it.

Knowing this, we brought an electrical alarm clock from home.

We used an adapter to plug it into the French outlets but noticed that the clock was running slow.

We switched to a converter, thinking maybe the 220 voltage was causing the problem somehow but it still ran slow.

Turns out it's not the voltage, but the frequency, that is the problem.

This website explains the issue (as well as all international electrical matters) well:

While it is easy to convert voltage, it is virtually impossible to convert frequency. Fortunately, the latter is of little importance. The difference in frequency between American and European current is of no concern. You will not damage any American item by running it on its proper voltage, but at 50 Hertz instead of 60 Hertz.

There is one caveat: electric clocks and clock radios will not keep proper time. This is because most electric clocks count cycles to keep time, advancing the second hand one second every time they count 60 cycles. Since at 50 cycles per second it takes 1.2 seconds to reach a count of 60, any American electric clock, be it electronic (digital) or motor driven (analog), will run slow by exactly four hours per day. You will not harm your clock, but it will keep terrible time.

For this reason, it is suggested you obtain an inexpensive travel alarm clock that either operates exclusively on batteries or is spring driven and wound manually. Not to worry about your computer’s clock, however: It keeps time via a quartz crystal and not by cycle counting, so it should keep perfect time in Europe.

No comments:

Post a Comment