Electromagnetic field from electric engine

AI Thread Summary
Concerns about electromagnetic fields (EMFs) from electric engines and batteries on a sailboat are discussed, particularly regarding living arrangements near these components. The consensus suggests that there is minimal EMF from a DC supply when the engine is not running, and the risks from electric motors are likely less significant than those from internal combustion engines. The discussion emphasizes that health effects from EMFs are difficult to prove, and many people coexist with high currents without issues. A magnetic compass can serve as a basic gaussmeter to detect strong fields. Overall, the advice leans towards enjoying the sailing experience rather than worrying excessively about EMF exposure.
rxahart
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Physics is not my forte, but I need some answers re EMFs. I want to buy a 30-ft sailboat that has an electric engine. (I have attached a link to the exact model for reference.) Further, my intent is to live aboard. I have been planning on making my permanent bed right over the top of the engine and at least 2 of the 4 AGM or gel batteries. How can I determine the amount of EMF from the engine/batteries when they are fully charged but disconnected from shore power? I know about gaussmeters, but I haven't been able to locate one locally yet.

Please state your qualifications for answering my question.

Thank you.

http://www.advancedmarineelectricpropulsion.com/index_files/Page497.htm
 
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Your question is a bit unspecific as to your particular fear. Why should there be any "EMF" from a DC supply, particularly if the engine is not running?
If I were you, I'd just enjoy the sailing. You would be getting more problems from the pollution from a internal combustion engine than you are likely to get unproven effects from a few amp hours of current flowing through your electric motor. There are many people who live in the constant presence of massive currents in power distribution systems. Permanent health effects have been a bit difficult to prove inconclusively afaik. If they had, there would have been some pretty expensive law suits, already.

Until you pay me as a consultant, I don't feel I need reveal my qualifications but I am, in general, very skeptical about the scare story thing, in general.
 
A magnetic compass works as a primitive gaussmeter.

If there's a strong field about you'll find it.
 
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