12 volt laptop charger query

[LazyTrucker]

Firstly I'm new here so forgive me if this is in the wrong place or a stupid query, I'm no electrician by any stretch.

I'm looking at buying a charger to charge my laptop my truck whilst engine is running mostly. I'd rather not go down the inverter route if possible due to employers concerns over them somehow damaging the truck wiring.

I've come across a dedicated charger supposedly for my specific laptop. It outputs 19 volts at 6.3 amps so 120 watts. My query is, is it even possible to output this from a 12v socket theoretically rated at 5 volts so only 60 watts. Output from socket is DC if I'm not mistaken and charger outputs AC I would think. I've no idea how the conversion works but I thought the power would be constant regardless of conversion i.e. if upped from 12v to 19v then current would reduce to ~ 3.1 amps. Am I completely wrong and confused?

Honestly I hope I am as the charger would be really handy in fact pretty essential.

Thanks in advance

 

[telectrix]

is the charger yo have seen designed for 12V or 24V input? what voltage is your truck? HGVs are usually 24V.

 

[LazyTrucker]

The one I've seen is for 12V, my truck also has 24V but it's much harder to come by domestic chargers that will work from 24V, I certainly couldn't find one to work with my laptop.

Here's a link to the one I'm looking at if it works. MSI Gaming GE62 Compatible Laptop Power DC Adapter Car Charger | Power4Laptops - https://www.power4laptops.co.uk/p/msi/gaming+ge62/compatible+laptop+power+dc+adapter+car+charger+1819159#.W4cGQlDTU0M

 

[LazyTrucker]

Just to clarify, my truck also has 12V outlets which I would use. I think the truck has a built in voltage dropper as most do these days.

 

[buzzlightyear]

12v Power Inverter Car 12 Volt 240v Mains Charger Laptop 70W Van USB travel 230v 5026637612206 | eBay - https://www.ebay.co.uk/itm/12v-Power-Inverter-Car-12-Volt-240v-Mains-Charger-Laptop-70W-Van-USB-travel-230v/192215995170?epid=1005420393&hash=item2cc0f75322:g:f3gAAOSwzH5bMNpq

 

[Richard Burns]

The adapter is probably designed for a 12V 10A power supply from the vehicle. If you only have a 5A supply then you could blow the fuse if you were running the laptop hard, however it should be fine for just charging the battery without the laptop running. Though in all likelihood the laptop be drawing power mainly from the internal battery only using the outside supply to charge the battery, if the battery was not too flat.

 

[LazyTrucker]

Thanks Richard, That's pretty much the conclusion I'd come to as well after thinking about it a little more. I'm thinking I'll just try it and see how it goes, maybe just have a spare 5A fuse on standby first. Now just to figure out where the sockets are fused.

Is there likely to be other things on the same circuit as the 12V outlets that may stop working if the fuse goes?

Thanks for the input buzzlightyear but I did say that the charger will draw upto 120 watts and that inverter is rated at 70 so I'm guessing it would get fried if the fuse didn't blow.

Worst case scenario would have me get a larger inverter and run it from a 24V outlet I guess. At least that way I'd be highly unlikely to overload it as they're rated at 15 amps so 360 watts. I'm thinking maybe a 300 watt pure sine wave would be best as I've heard it's best to double the potential required draw to account for power loss. Does that sound about right? Not sure how long the trucks battery would last if it accidently got left on with that though

 

[Squid]

24v Universal DC Converter Dropper Laptop TV Power Adapter 3300mA 80w 15v-24v - Radio, Electronics & Leisure, FREE 24h Delivery Nationwide - https://damsu.co.uk/24v-universal-dc-converter-dropper-power-adapter-3300ma-80w-15v-24v.html#.W4fIbC3MxL4

 

[gnuuser]

Thanks Richard, That's pretty much the conclusion I'd come to as well after thinking about it a little more. I'm thinking I'll just try it and see how it goes, maybe just have a spare 5A fuse on standby first. Now just to figure out where the sockets are fused.

Is there likely to be other things on the same circuit as the 12V outlets that may stop working if the fuse goes?

Thanks for the input buzzlightyear but I did say that the charger will draw upto 120 watts and that inverter is rated at 70 so I'm guessing it would get fried if the fuse didn't blow.

Worst case scenario would have me get a larger inverter and run it from a 24V outlet I guess. At least that way I'd be highly unlikely to overload it as they're rated at 15 amps so 360 watts. I'm thinking maybe a 300 watt pure sine wave would be best as I've heard it's best to double the potential required draw to account for power loss. Does that sound about right? Not sure how long the trucks battery would last if it accidently got left on with that though

most charger ports and lighter sockets are wired so there is no power present when the ignition is turned off, but that is not always the case.
its best to check the system out first!