Using a laptop on board on DC power

[jaapbood]

I recently changed my onboard laptop, because it was getting too old. Now have a DELL 6330. Excellent laptop. However, I cannot get it connected directly to my house battery. I do have a dc-dc converter to produce 19.5V. However the regular 220v adapter seems to have some kind of battery management inside. It is connected with 3 wires. If I measure the power it’s not stable but changes all the time.
Is there anyone who uses a modern (19.5v) laptop on board, connected to dc power?

[gmakhs]

Buy a car adaptor for that laptop , you can get an official one or one from Amazon I used to run my.laptop like that.

[hellosailor]

You might need to ask Dell, and good luck trying to get a real answer from them.

Since the products may ship to the EU, there may be something in the 220 power brick that is monitoring battery state and power consumption, and shutting down the brick to conserve power, when charging is not needed. Dell could install charge control logic in the laptop, or in their supplies, or both--you'd have to check with them.

If your "12 to 19.5" adapter is homebrew or no-name, no telling what it does. It might pay to find out if Dell makes a matching DC adapter for that laptop. At $50 it would be worth the peace of mind, at $100...not so fast. Knowing Dell, the hardest part will be to get the facts out of them.

[LeaseOnLife]

Originally Posted by jaapbood

I recently changed my onboard laptop, because it was getting too old. Now have a DELL 6330. Excellent laptop. However, I cannot get it connected directly to my house battery. I do have a dc-dc converter to produce 19.5V. However the regular 220v adapter seems to have some kind of battery management inside. It is connected with 3 wires. If I measure the power it’s not stable but changes all the time.
Is there anyone who uses a modern (19.5v) laptop on board, connected to dc power?

For the boat I have always used Lind 12V Auto Adapters, for all kinds of laptops. Currently I use a Dell E7470 and have a Lind 20V adapter. I did have a 19V adapter for a previous laptop, but that didn't do for the 20V Dell laptop despite having the right cable. Your 6330 is also listed as 20V laptop on the Lind website:


https://lindelectronics.com/product/de2045-2690/


Look for that part number on ebay and you may find one for a few bucks. Be aware, there are some battery saving versions of these power bricks which turn off when battery voltage is below ~12.6V.



Dirk

[Triumphant]

When buying a PC always look at the amount of Watts they use usually shown on the brick. (my Lenovo PC will charge at either 45 or 65 watts other may pull up to 120 watts) If I cannot get a 12V device to power the PC I use one of these

https://www.amazon.com/BESTEK-Power-...XXG3MWJS3RFBSB

[john61ct]

Some mfg / models require their proprietary charger.

I know Apple and HP have been offenders, and pretty sure Dell was the third.

See if they have a "car adapter" for your model.

[BigAl.NZ]

Yes - Dell has a center pin on the charger tip which is to do with the battery. You will need a 12v car charger that is compatiable. Best get one from Dell.

[hellosailor]

Lenovo also "fakes" a proprietary adapter. They use a pull-down resistor across the power leads, in the end of the cable. If your computer detects the wrong value of pull-down resistor, it knows the power supply is not the OEM value.

So on a hungry machine with a 175W power supply (!) you can run the machine very nicely even on a 90W supply, assuming you are trying to run it OR charge it, not both at once, and you've chosen things like SSDs instead of moving platters. But because you are using a wrong power supply--the machine will prompt you to go fund the right one before the world comes to an end in a rain of hellfire.

Proprietary, but a lot of FUD.

Meanwhile for 20 years I've been trying to find out why we need 19v power supplies, when nothing in a laptop runs at more than 5 volts these days, except the screens, which boost their own voltage, and the batteries, which could charge just as well from 12. Apparently all the real engineers have been tossed in a dungeon, or their families are being held hostage, because none can be found to comment. (The old amperage/voltage/wire size business is not relevant to the larger issue, you can still push more amps at 12 volts if you need them, or slim the machine down and not need them. 20 years ago, Toshiba HAD 12v machines that they supplied to ocean racers, so the job can be and has been done before.

[sailcrazy]

I bought and installed an 12vDC to 110v inverter from an auto parts store(300watt w/auto fan). I connect it to my Batt Bank, plug in my laptop charger, and the laptop charges like we're back at home! I hard mounted it behind the Nav panel, and connected it to a conventional duplex outlet on the Nav Panel. Small, compact, cheap, and it works!

[moseriw]

I have my 220VDC supplied by an 350W mounted inverter and the ability to switch to the second 1,5 Kw inverter. So IO do not see an problem to solve.

[roland stockham]

As others say Dell uses a system which identifies the charger, if it is not a genuine Dell one it either wont charge or shuts down to a minimal charge rate. There is no way round this! I would recommend you get a second charger if heading 'out there'.
I have tried a variety of 'car chargers' that plug directly into 12v but in every case they have used more power than running the standard mains charger from my onboard 1500w inverter. In theory small adapters should be more efficient but I guess the problem to be that the 12v adapters are build down to a very cheep price and are very inefficient.

[Dockhead]

I use a Targa car/truck adapter for my Dell XPS 13. Works great.


You can even get a genuine Dell one for not too much money:


https://www.amazon.co.uk/Original-No...gateway&sr=8-6


This is not a big challenge.

[hellosailor]

Double converting (12 to 110 to 19) certainly will work. You may be losing 5-10% in each converter, so possibly 10-20% overall loss, which may or my not be significant compared to your battery bank.

Then there's the 12-to-110 inverter. An awful lot of those from chain stores are junk inside, and they tend to fail with often upsetting consequences. Like, taking out whatever is plugged into them, or sometimes catching fire. Not to say there aren't good cheap inverters--just that a brand name, purpose built, single piece of equipment is very much more reliable as well as more efficient in the long run.

[john61ct]

Originally Posted by roland stockham

I have tried a variety of 'car chargers' that plug directly into 12v but in every case they have used more power than running the standard mains charger from my onboard 1500w inverter.

Is that actually A/B testing measuring Ah per hour with a standard benchmark app running?

And what inverter?

[john61ct]

Originally Posted by hellosailor

Not to say there aren't good cheap inverters

Would be a great public service to name any.

Indeed worth a dedicated thread.