Inverter for portable computers

[westernman]

Without knowing the model and BIOS it's difficult to even hazard a guess.

Was the voltage set to the correct 19v?
Polarity?

As the two most obvious ones.

Yes. And the polarity was the right way round (measured off another dell charger).

 

[Heckler]

Tried that - same result.



This is probably a good idea. Does the tip for Dell really work?

I tried one attached to a generic mains converter and although it supplied power to the computer and I was able to run the computer with discharged batteries, the computer complained that it was not a Dell charger and did not charge the batteries at all. Is this a new Dell thing?

Actually is was a real dell tip cut off a broken Dell mains charger and attached to the cable of the generic one.
So it looks like there is funny business going on. Also the computer complains if I plug in a Dell 65W charger - it knows it is not the original 95W one (although it does not complain about it not being Dell as in the previous case - how does it know??)





That is what I thought.

Dell and some HPs (mine!) use a special tip, the outside and middle pin give the feed that will run the battery BUT there is a connection to the inside of the outside housing of the tip (if you se what I mean!) If you strip the Dell cable you will see there are 3 bits of wire, 2 that look like a co ax shroud and the third that is for the normal middle pin. I understand that the second circuit is to sense the battery voltage and adjust the charge accordingly. The prob with the generic charges is that they look the same, including the tip BUT only have two wires going to the tip and the tip outside is the same as the inside i.e no insulation between the metal housing. Consequently they will run the pooter but wont charge!
Stu

 

[Jameshow]

I saw online power inverters with the small clips which hooked directly with the battery, but i think it is an awkward solution. I have not considered the possibility of drawing anpei. I was just thought not messing up the laptops. It has a screen 14'' and 67w.

 

[Shearwater]

I bought a 150w inverter from Lidl today and it says in the manual

"No Output Power- possible cause and remedy........
* Inverter is not fully warmed up; switch the inverter off and on until the attached device is supplied with power. Repeat this process as necessary"

Just a thought ?

 

[John the kiwi]

Dell power supplies

I too bought an aftermarket power supply for my laptop when i went on business trip without the dell PS unit. The aftermarket unit would run the laptop but would not charge the battery so i went looking for reasons.

It would seem that Dell had a few problems a few years ago with Lithium Ion batteries catching fire and exploding and that sort of thing and being a US company this resulted in mega-buck lawsuits. To protect themselves they somehow key the batteries to the power supplies so that they only work with Dell chargers.
Not sure if it is done with a wire connection or a coded signal over the supply itself. (It is a trivial exercise to layer an ID signal on any circuit.)

Once i read the explanation i could see their point really: Cant be any fun being sued for millions by some deadhead that plugs in a totally inappropriate charger and explodes the battery!

 

[Beyondhelp]

I have a Xantrex XPower 300 which is supposed to deliver 300W (600W Peak) of modified sine wave. It is hardwired with substantial wiring directly to big +ve and -ve bus bars in the boat (i.e. not through a silly cigar lighter).

However, it will not work with my portable computer mains charger (Dell 65W). I have also tried it with someone else's computer as well with the same results.

In both cases, the undervoltage alarm goes off in the inverter and the computer does not get any power.

What is going on? Does it really have to be a pure sine wave for these cheap chinese battery chargers that Dell uses????

Laptop power supplies sometimes have LARGE inrush currents.

I have three 600w/1200w peak inverters and they ALL take a few attempts when starting if I plug my dell 85w charger into the, yet will run 500w halogen lights fine.

I suspect your having the same trouble.

'Modified Sine' inverters switch their outputs like a square wave, which for anything that takes a surge on start up is horrific, for both the inverter and the device. Pure sine-wave has a nice zero crossing point and so wont have the same effect.

Solution is to get a small sine wave inverter or a larger modified sine wave one, also your overload protection on the inverter may be too sensitive.

All of the above I have personal first hand experience with.

 

[Bobobolinsky]

Thanks to this thread, I will definitely not replace my dying Dell Inspiron with either another Dell or an HP

The battery failed last year after 3 years.

OEM battery was like £100

Cheap battery was £35. But what a lot of ****

"Your Dell detects that a none Dell battery is fitted and therefore will not charge it"

Switch on and off a few times, it says "do you wish to see this warning again"

Click "no" and it charges

Wanted 12v unit, as I use it for reading ODB on the cars, again hexagon plug so need to buy a Dell 12v unit for £75

Oh and the keyboard and mouse failed and I use externals.

 

[Beyondhelp]

Thanks to this thread, I will definitely not replace my dying Dell Inspiron with either another Dell or an HP

The battery failed last year after 3 years.

OEM battery was like £100

Cheap battery was £35. But what a lot of ****

"Your Dell detects that a none Dell battery is fitted and therefore will not charge it"

Switch on and off a few times, it says "do you wish to see this warning again"

Click "no" and it charges

Wanted 12v unit, as I use it for reading ODB on the cars, again hexagon plug so need to buy a Dell 12v unit for £75

Oh and the keyboard and mouse failed and I use externals.

Sounds like bad luck. I'd have another Dell. Mine gets a lot of physical use, in rough enviroments (automotive/motorsport) and has thus far (6 years) been flawless. Granted it was a high spec when new, but oem batteries are quite often from better sources and do last longer than others

I think actually that they seem to die sooner when used less. I had three batteries from new with mine. One small and two larger (all dell) I rarely used the smaller one as you wouldn't get an hour out of it. It probably had less than 1/10th the use of the other two which would get frequently cycled, they are both still fine, and the small one I had to throw out some time ago.

I see loads of laptops with dead batteries, the majority of them seem to spend their lives plugged in and thus never really used, they seem to die sooner!

 

[Quandary]

I only recently discovered that Dell advise turning off the mains supply to the charger when the lappy is switched off in order to ensure the battery life is not unduly curtailed. Until I read that the charger was plugged in and on except when the laptop was on an outing to the boat, where we use a 12v-19.5 volt adapter.
I can not complain about the longevity or the durability of our relatively cheap Inspiron laptop it goes sailing frequently and when at home has been on every day for about 8 years.