Smoking Adaptor

cormie · 23-08-2007 10:51am #1

I bought a 12v to 240 mains adaptor in Halfords for my van so I could plug my laptop in.

The adaptop has this spec:
Max Power Rating: 60 watts
Surge Capacity: 150 watts
Standard current: 0.25 amps
Nominal Voltage 12 volts DC
Efficiency: 90%
Wave form: modified sine wave
Mains output voltage 220v/240v
output voltage of usb: 5v
output frequency: 50hz

Now on the plug part (black box with the green light) of my laptop is this info:
AC ADAPTER
Model: ADP-90sb bb
input: 100-240v~1.5a(1,5a) 50-60hz
output: 19v -- 4.74a (4,74a) (-)--C--(+)

When I had it plugged in to the Halfords adaptor yesterday with the laptop on, the power kept going on and off (even the green light on the halfords thing did and when I plugged the laptop out and kept the adaptor in the cigarette socket, the green light would stay on). Then I put the laptop in standby and the green light on the halfords thing remained on, but then I saw smoke coming from it:eek:

Can anyone see in the above spec, why it wont work and could somebody please link me to one that will as I have 3 broadband and my laptop battery is terrible so I can only get about 20 mins out of it and then have nowhere to charge it if I'm out and about in the van.

Any feedback appreciated:)

fletch · 23-08-2007 1:58pm

Same thing happened my sister, bascially the adaptor isn't powerful enough to run the laptop, she bought a more expensive one and it works fine.

Anti · 23-08-2007 3:04pm

4.7a at 19v. Im supprised it didnt mealt when trying to power the laptop.

cormie · 23-08-2007 3:49pm

Ok, so would anyone have any idea what kind of one I'd need? A link to one on Ebay or anywhere would be greatly appreciated as I don't know what I'm supposed to be looking for. Is it possible to get a 12v/240 one that would be powerful enough for the van?

Stephen · 23-08-2007 4:12pm

Any idea how many watts your laptop charger consumes?
This would do the trick but is probably overkill! http://cgi.ebay.ie/500w-DC-AC-Power-Inverter-3-yr-gty-Caravan-Boat-Car_W0QQitemZ150153256183QQihZ005QQcategoryZ76066QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Cuddlesworth · 23-08-2007 4:40pm

Most Laptops charge at around 60-90 watts. Getting one rated at 100+ watts would be recommended.

cormie · 23-08-2007 4:52pm

Does it not say how many watts it consumes in the info I put about the adaptor above, I thought that was the info that said it

If it makes a difference, the laptop is an Acer Aspire 5021WLMi

Thanks for the help so far!

Cuddlesworth · 23-08-2007 5:00pm

You did, the converter is rated at 60 watts maximum. As I said a laptop charger will consume between 60-90 watts depending on parts used. A gaming laptop can use up to 120 watts. Then you need to consider the efficancy of the charger, which means it may use more then its spec to simply supply the power to the laptop.

Adding to that, adapter used has a max rating of 60watts. You never want to use any electrical switching component at its maximum, because they generally don't last more then 5 minutes due to manufacturers hyping up their specs. Finding one with a 100watt minimum supply would do it, but I would go higher.

cormie · 23-08-2007 5:05pm

Ok thanks for the info, but does this spec on the actual laptop charger (supplied with the laptop) not give an exact measure on what I need?

AC ADAPTER
Model: ADP-90sb bb
input: 100-240v~1.5a(1,5a) 50-60hz
output: 19v -- 4.74a (4,74a) (-)--C--(+)

Stephen · 23-08-2007 6:12pm

It doesn't say how many watts it consumes. There's probably some way to mathematically calculate it but I've no idea how

cormie · 23-08-2007 6:27pm

Ok cool. So do you reckon a 200watt car adaptor thing would be ok?

You know a Microwave the way they are rated by watts? 700, 800 etc. Does that mean I'd need an 800 watt adaptor thingy to get them to work in my van? Not that I will or anything but just out of curiousity:)

Anti · 23-08-2007 7:17pm

cormie wrote:

Ok cool. So do you reckon a 200watt car adaptor thing would be ok?

You know a Microwave the way they are rated by watts? 700, 800 etc. Does that mean I'd need an 800 watt adaptor thingy to get them to work in my van? Not that I will or anything but just out of curiousity:)

Thats power not consumption. But 1kw should do the jobbie

power is (V)x(I)

Comsumption would be rated in amps.

Snowbat · 23-08-2007 9:11pm

cormie wrote:

input: 100-240v~1.5a(1,5a) 50-60hz

Assuming the manufacturer of your laptop power supply is quoting the current at 100V, 100 * 1.5 = 150 watts. But that's a maximum and would allow for full charge rate while running at 100% CPU/GPU with some power-hungry USB devices hooked up too. Typical consumption would be less.

You'll need an inverter with a capacity of at least 150 watts output to be sure and you'll need to run a heavy cable direct to the battery to power that since at maximum output it will draw more than 13 amps at 12V (more than your cigarette lighter socket is rated for).

Snowbat · 23-08-2007 9:55pm

Anti wrote:

Thats power not consumption. But 1kw should do the jobbie

power is (V)x(I)

Comsumption would be rated in amps.

Actually a microwave oven with an 800 W magnetron would need just over 1.3 kW of electrical power, assuming 64% efficiency. The electrical power consumption (1312 W) and the magnetron RF output power (800 W) are both in Watts but they measure two different things.

Current is rated/measured in amps.

zilog_jones · 23-08-2007 10:13pm

With your laptop, there are also laptop power adaptors designed for cigarette lighters. These would be more efficient (they just convert DC to DC, not DC->AC->DC) and they're a lot smaller too. Maplin sell a "high power" one for €50 - it says it can do 6A at 19V so it's plenty for your laptop (the other one they sell isn't powerful enough).

...you'll need to run a heavy cable direct to the battery to power that since at maximum output it will draw more than 13 amps at 12V (more than your cigarette lighter socket is rated for).

Cigarette lighters are usually rated for 15-20A according to Wikipedia. The one in my Fiesta has a 15A fuse anyway.

cormie · 24-08-2007 12:09am

Thanks again, I think I'd prefer to just go with an inverter, I don't want to have to get a new cable every time I get a new product, would be a lot handier just to have an inverter ready for use:)

Snowbat, what do you mean a heavy cable? From what to what? The battery of the van or the battery of the laptop? What difference would cable size make do you know?

Zilog, you reckon a Ford Transit battery (or cigarette adaptor) has enough amps for what I need then yeah? Would you agree Snowbat?

Should this: http://cgi.ebay.com/200W-DC12V-to-AC220V-power-inverter-Car-charger-USB-5V_W0QQitemZ110162602933QQihZ001QQcategoryZ60252QQrdZ1QQssPageNameZWD2VQQcmdZViewItem

do the job?

legs11 · 24-08-2007 12:17am

the output CURRENT of the halford adapter was rubbish, your laptop needs 4.7amps

as for the wattage, the power supply of your acer draws whatever it needs, you can whack on a 1000watt power supply if you wanted, the important figure here is current, more current = more expensive.

you should be able to get a suitable adapter for the car if you get googling or ask some others. you need one at around 4.5amps@ say 80watts , if you can manage to get one like that ............

an inverter might be your best bet, but prepare for a lot of flat batterys

zilog_jones · 24-08-2007 11:49am

cormie wrote:

Zilog, you reckon a Ford Transit battery (or cigarette adaptor) has enough amps for what I need then yeah? Would you agree Snowbat?

Well snowbat worked out 150W @ 230V would be about 13A @ 12V (I forget how to work it out myself - it's been a while since Leaving Cert Physics

), and if my Fiesta's cig lighter can take 15A I'm sure your Transit can take the same, if not more. Check the fuse box anyway just to make sure (and/or manual if you have it).

cormie · 24-08-2007 2:00pm

Hmm, this is interesting.

I have one of these:
http://www.pcpro.co.uk/processors/reviews/60761/belkin-ac-anywhere.html#latestPrices

the 140W one.

it says on it, at the mains plug, Output 230v AC +/-5%
it says where the cigarette cable goes into it, Input 11-15v
then above that, it seems there is a fuse, which says FUSE 25Amp
It says on the top of the thing itself "Ac Anywhere, Belkin, 140Watts"

by the sounds of it, this should do the job? But it doesn't.

If you look at the last line of that review I linked to, it says something about an alarm sounding if the car battery goes below 10.6v or something. Whenever I plugged the AC Anywhere in, it would alarm, even I think if there was nothing plugged into it.

Luckily I have 2 cigarette sockets in my van, and I think I blew one using the AC Anywhere with my laptop connected, and then I had a 3 way socket, I plugged the AC Anywhere into that, and I think I blew that too.

The same thing happens when the vans engine is running and not.

If the AC Anywhere should do the job, then why isn't it working I wonder

zilog_jones · 24-08-2007 4:41pm

Sounds dodgy - maybe there's something wrong with the connection to the cig sockets. Do you have or know someone with a multimeter? I think it would be a good idea to see what voltage is actually going to the lighter sockets and from the battery directly.

cormie · 20-09-2007 10:18pm

I picked this up at Aldi in Tallaght this evening and it seems to be doing the job, it's charging and there's no sign of smoke or anything and it seems to be giving a good constant supply of power. The only thing is there's a slight buzz from the little box that connects the plug to the laptop on the laptop power supply. I haven't heard this buzz when it's plugged in at home but as far as I can see, it's not causing any ill effects. It's advertised for €40 but I'm not sure if they are clearing stock or what, but it went through at €30 at the till:)

It says something like DC input 15v on it I think, maybe that's why there's a buzz with my thing being 19v?

zilog_jones · 20-09-2007 11:03pm

I saw that in Aldi a few days ago too - looks like a good price. 300W @ 230V should be plenty for a laptop. I think inverters generally do buzz - the ones I've heard do anyway.

cormie · 21-09-2007 3:36am

zilog_jones wrote:

I saw that in Aldi a few days ago too - looks like a good price. 300W @ 230V should be plenty for a laptop. I think inverters generally do buzz - the ones I've heard do anyway.

Yeah, I think even at €40 it was a good deal, but mine scanned at €30 so even better:)

It's not the inverter I bought in Aldi that's buzzing, it's the little black box on the power chord for the laptop that's buzzing

Smoking Adaptor

Comments