I have a sailboat that uses 110-volt, 60-cycle power. What do I need to be able to plug into 220-volt, 50-cycle shore power?
Sue & Larry respond:
Thanks for your question. In North America, 110-120 volt electricity is generated at 60 hz., or cycles Alternating Current. Foreign electricity is usually 220 or 240-volt generated at 50 cycles Alternating Current.
North American 220-240 volt power is wired with two hot leads (110-120 volts each), one common, and a ground. To convert 220-240 volt power in North America to 110-120 volt, you simply disconnect one of the hot leads. In most foreign countries where 220-240 volt power is the standard, a single hot lead is used to carry the full voltage. To reduce this foreign 220-240 volt power to 110-120 volt, a step-down transformer is required.
A step-down transformer will allow you to plug into foreign power either shoreside or at marinas worldwide (assuming you can find the right plug), but it will not change the cycles of the Alternating Current.
The difference in cycles is most noticeable in the operation of motors. Appliances will run slightly slower on transformed 110-120-volt, 50-cycle power. This is usually not a problem, but it is something you should keep an eye on. Obviously, if a motor stalls or buzzes you should immediately stop its operation. This cycle difference may also have an affect on analog clocks and any sort of timing circuits that use the Alternating Current cycles as a means of keeping time. Most modern electronics: battery chargers, stereo, computers, etc., should not be adversely affected by the difference in cycles. We’ve run our laptop computer, sewing machine, and chargers for cordless tools on a step-down transformer and they’ve all performed fine.