A reader wanted to know how to charge his Acer laptop from a narrowboat. Using his knowledge of charging from a car's cigarette lighter port, our Helproom Expert explained.
QUESTION I'd like to charge up an Acer Aspire 5741 laptop using a 12V (300 amp) battery with no inverter on a small narrowboat. The battery is used to start up the engine and provide power to the internal lighting and water pumps. Is this possible and, if so, how? I don't have a 12V car-style cigarette-lighter socket in the boat at present, but I'm sure one could be fitted. Nick Steinitz
HELPROOM ANSWER No laptop will require anything like 300 amps, Nick. A more realistic maximum is closer to 5 or 6 amps. The problem you're most likely to run into is that laptops typically use power supplies running at more than 12V. The Acer Aspire 5741, for example, uses a 19V PSU rated at 4.74 amps.
If you're willing to fit a cigarette-lighter socket, then a car adaptor is likely to suit your needs. You'll need one with an adjustable output voltage that supports 19V. Maplin sells a 120W adaptor with a selection of interchangeable tips for the laptop end of the cable. We haven't been able to test this, so you would need to ensure that one of the tips fits – perhaps by visiting your local store.
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Comments
Andrew Denny said: I presume by 300amp battery Nick means a 300amp-hour 12v battery bankSpeaking as a narrowboater whos had the same problem myself Id say the best option would be a simple 12v-230v inverter that works off a 12v lighter socketMaplin do such models ranging from simple 150W inverters which should be just powerful enough and start around 30 However a higher 300W models would offer a little leeway in power terms in case you later want to use something that draws more powerThis is a more flexible approach because you can use it to powercharge many more items such as shavers mobiles and AA battery chargers not just your laptop Some of these inverters have USB power sockets built in as wellOne small drawback is that they often have an overhead that consumes power even if you havent got anything plugged in so will drain the battery unless you remember to disconnect them or switch them offA common problem with the dedicated laptop chargers that Paul Monckton mentions is that they often have every tip except the one you need even if you have a popular computer I found this out to my cost when I bought one from Maplin a couple of years ago only to find it didnt support my bog-standard Dell Roll on the universal standardised charger