Can I make a 5 amp 3 pin plug to USB adaptor?

My boat (in the UK) has some 5 amp round pin plug sockets. Can I and how would I, make an adaptor so I can charge phones and a laptop? I’m thinking a USB connector. I’ve never done anything with electronics more than plug something in!!

by Sofii
March 14, 2021

5 volt is the limit, but the maximum current is also limited, 100 mA per load up to 500mA through many loads ( 2.5 W ) for basic USB 2 and 900 mA (4.5 W ) for USB 3. You can probably find a "usb adapter wall charger" at eBay for a couple of British Pound. I am not sure about what kind of regulation those adapters must follow to be used on a boat, though (insurances and other legal stuff). You can probably find those in more or less specialized local store. I assume that you don't have "Canadian Tire" stores in England, but you surely have something similar :-)

by vanderghast
March 15, 2021

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