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Post by robertarthur on Nov 24, 2021 17:00:12 GMT 1
Some car passengers can't get enough of it: working all day long. Also when travelling for many hours in, or to France, the sound of a clicking laptop keyboard from a back seat. Un moment donné it's the battery that says: enough is enough, I'm going to sleep now, save your data. The answer is of course a little inverter, from 12 V DC to 230 V AC. But not all inverters and laptop power supplies are created equal. Sometimes a specific combination simply refuses to work. My third inverter seems - touch wood - to be rather cooperative with power supplies of HP, ASUS, LENOVO etc. Not that it produces a nice sine wave, it's just square wave approximation, with an effective RMS voltage of around 230 V, not too bad. Keeps the backbenchers productive. |
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Post by Polarengineer on Nov 24, 2021 17:52:53 GMT 1
Would it not be cheaper to rig a pot and drop the 12 volt to the usual 5volt input to the machine?
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Post by pcpa on Nov 24, 2021 18:35:04 GMT 1
5 volts is usual for a laptop?
I guess mine is old and outdated then at 18.5 volts 3.5 amps.
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Post by robertarthur on Nov 24, 2021 19:00:40 GMT 1
@ Polarengineer, most laptops need an input of around 18 V dc for recharging their batteries. The 5 V dc present in the USB type supplies to charge a mobile phone is not enough. There are expensive (HP=High Price...) special cables for sale, with a simple dc/dc converter chip inside, from 12 V in the cigarette lighter socket to around 18 or 19 V dc. The cheaper option is a simple dc/ac inverter. If you can live with the slightly higher thermal losses, from dc to 230 ac and then from ac down to 18 V dc, the higher power consumption (1 watt?) is probably not an obstacle. The extra cost is dwarfed by the still rising fuel prices and the use of so many other gadgets at home.
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Post by landmannnn on Nov 25, 2021 10:21:23 GMT 1
Not quite as tidy, but I have a jump starter device with a built-in 230v output.
Charges from the cigarette lighter socket and easily capable of charging multiple devices off grid.
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