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Bob Austin of Pensacola, FL asks:

In a prior question, Jim Leishman commented that one of the Nordhavn 46s was using a cheap stepdown transformer in Europe. We did this also, but it should be used only for resistive loads--that would include the water heater, heaters with small fans may be OK, pure element heaters are fine. Many battery chargers do run well on the 50 hz. However many motors will not - especially refigerators/freezers, washing machines, watermakers, etc. Microwaves will not do well as far as the cooking. At one time the entire US was 50 hz and the country was changed in the late 1940's mostly because of better transmission characteristics of the 60 hz power. At that time all clocks (synchronous motors) refigerators, washers, industrial motors, etc. had to be changed. Resistive loads, includng light bulbs did not.

Congratulations on a trouble free trip--It took us over a year to get all of the red dust out of the crevices and rigging when we cruised Europe.

Dan Streech responds:

Thank you for your comment about using a simple step-down transformer while in Europe.

I often see your name and comments on the Trawler World list and nearly always find myself in agreement with your detailed and thoughtful answers. Your wealth of experience comes thru in your answers and I have learned a few things from you.

You are correct that when operating a 60Hz boat in a 50Hz country, there is normally more to the story than the use of a simple step-down transformer.

There are so many factors to consider, that we take each boat on a case by case basis when preparing a 60Hz boat for temporary operation with 50Hz and thus a complete foolproof guide canít be presented in this forum.

Some of the approaches however are:

1. We rely on the fact that Cruisair air-conditioning can operate on either 50 or 60 Hz, so we always provide a separate AC inlet for it. A normally 120VAC 60Hz boat (N35, N40 and some N46s) would use the simple step-down transformer described above. A normally 240VAC 60 Hz boat can plug directly into European (or Hong Kong, Singapore and Australia) 50Hz power which is usually 230VAC.

2. We rely on an inverter(s) to provide 60Hz power to the items such as refrigerators, freezers, microwaves, trash compactors, TV sets and audio systems.

3. Since some inverters (such as the Trace SW series) are too smart to accept 50Hz power and others (such as the Heart) would pass thru unwanted 50 Hz power, we donít plug in the main house power cord. Instead, we provide a separate dedicated 50Hz inlet with the power directed to a 50Hz 230VAC battery charger.

4. The hot water heater (as you mentioned, a resistive load and not frequency sensitive) is temporarily rewired over to the air-conditioning buss.

5. Ovenís and cook tops are tricky and made more so because they are normally 240VAC. Old dumb units are not frequency sensitive but many new units with microprocessors are. We donít chance it and recommend:

  • Equip the boat with LPG from the beginning (applicable to the N35, N40 and N46).
  • Run the generator.
  • Use two Trace SW inverters configured in a ďseries stackedĒ configuration which then     simultaneously produces both 120VAC and 240VAC 60Hz (applicable to the N50, N57     &N62).
  • 6. Water makers are typically not run at the dock and therefore can rely on the generator.

    7. Washer/dryers can be carefully run from the inverter.

    Please note that the above is only a glimpse into a complicated subject that must be talked thru on a case by case basis. For example, I havenít even touched on isolation transformers, GFI circuits, safety, neutral/ground bonding, color coding etc.

    I hope that the above helps some readersÖ and has not caused further confusion.

     

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