Voltage & frequency

[romachko]

Every one by now has some idea about what to take to Europe to cope with electrical difference.

If your gadget is a DC operated or power device (like iron), the solution is simple: get a cheap transformer kit with proper amp rating.

If your gadget is AC based, just forget it. I�fll tell you the reason. LP already told you AC motor rated at 60 Hz won't work properly at 50 Hz. So, I don't want to repeat. For small current, you can convert the current from AC to DC and put it through a �gchopper�h to produce current at any frequency desired. I looked at 5 hobbies and industrial electric/electronic catalogues. None is selling it. It appears that you have to build it by yourself. Would I do it? It depends on how much I get paid, certainly not for my stupid wall-plug-in electric clock. For larger equipment the converter will be more complex and bulky.

You have a good model in Japan about 50 vs 60 Hz problems. The east half of Japan is on 50 Hz and the west half on 60 Hz. The reason: The east half hired the firm from England and the west half from Germany when Japan was an industrially underdeveloped country. They�fve got stuck ever since. When people move from Tokyo to Osaka, most of them donate or simply get rid of their electrical appliances and buy all anew. How does an industrial firm cope with the problem? They install a heavy duty converting equipment.

[LP]

... in response to Voltage & frequency, posted by romachko on Sep 11, 2004

[This message has been edited by LP]

....To clarify, I didn't say a 60 cycle motor wouldn't run on 50 cycles. It all depends on the motor type and if it's powered directly.

If it's a synchronous motor it will run, but run slower. That may or not may be issue. Things like direct powered analog AC clocks, turntables, or any other device that depends on line frequency for proper operation will  be useless but something like an electric shaver should be OK. (There is a power factor issue but for intermittent use it can be ignored). Since an electric motor is also an inductive device (in the electrical sense it's not all that different from an iron cored transformer) the fractional horsepower motors found in many direct powered appliances won't, generally speaking, be a problem on 50 hertz when used for intermittent duty.

The other thing about an inverter is most output a modified sine wave. This can be an problem depending on what you power with them but it's seldom an issue for travel needs. You don't need an inveter, a voltage converter will be fine. It's important you rate the converter for more than the planned load and whether it will used for intermittant or continuos duty. Pick a converter who power capability (power by definition is rated in watts) is at least 25% higher than the wattage of the load. 50% is even better. This is for mainly for continous duty applications and because inductive loads (motors and such) have inrush current when first energized.

I'm oversimplifying much of this but you get the idea. Also this applies to step down converters. In the end just buy a decent converter with an adaptor (if needed) and rate it high enough to have some wiggle room considering the planned load and duty cycle. I prefer the ones that come with built in adaptors that cover all countries. You simply slide out the adaptor you need and plug it in.

On another topic, I recommend you also always carry a good flashlight when traveling, especially in the FSU. The small ones based on the Luxeon Star LED are best. I carry either the Surefire L4 or A2 Aviator when I travel. Surefires are the finest in the world but some may cringe at spending $150 on a flashlight. For those the Streamlight Luxeon Junior is excellent and fairly cheap at around $28. It's regulated, Luxeon based, and uses AA batteries. Makes a great FSU gift too, if you have a relative in the FSU who is a gadget freak they're bound to treasure it.

[romachko]

... in response to Voltage & frequency, posted by romachko on Sep 11, 2004

If you have some experience in electronics and wiring, I am pleased to send you the schematic of a circuitry for a simple chopper, or frequency generating circuit. It includes a 555 timer chip or VCO (voltage controlled scillator), as a driver and a power transistor, as an actuator. The amp rating depends on the power transistor. You need an oscilloscope to fine-tune it. The cost: less than a buck to a few bucks, depending on the quantity and the supplier, plus your labor. The schematic is free but I refuse to give instruction on line or telephone. If you are in the vicinity of Peoria, ILL, I am willing to give you hands-on instruction free of charge at my home or at a university lab. If you are totally a novice, please don't bother because it will be a waste of time. If you are really interested, please E-mail me.