Laptop Charger
04-03-2004, 03:03 PM
#1
Launching!
Thread Starter
iTrader: (3)
Join Date: Dec 2001
Location: Horsham PA
Posts: 231
Likes: 0
Received 0 Likes
on
0 Posts
Laptop Charger I have a Compaq Armada M700 laptop. I checked the battery and it is a 14.8VDC battery. My question is- Can I just make up a jack to plug into my cigarette lighter then into my laptop, or do I need to purchase one? Will it hurt anything to just plug directly into the 12V source of the car and to the computer? Thanks, Sam
04-04-2004, 02:32 PM
#3
TECH Veteran
iTrader: (11)
Join Date: Jul 2002
Location: Elmhurst, IL
Posts: 4,332
Likes: 0
Received 0 Likes
on
0 Posts
What I would get is a hardwired 12volt power inverter. Trying to run a laptop through your Cigarette lighter will probably draw too many amps and pop the fuse. Just use the hard wire kit and wire it directly to either the battery or under the hood at the fuse box.
04-04-2004, 02:57 PM
#4
Moderator
iTrader: (11)
Join Date: Mar 2002
Location: East Central Florida
Posts: 12,605
Likes: 0
Received 6 Likes
on
6 Posts
You need to look at the charger output voltage, not
the battery itself. If the charger voltage is 15V then
you may be able to rig a straight plug. I did this on
the old Toshiba I was using and it worked fine; it
would not charge, sitting with engine off, but would
run off it without depleting the laptop battery; with
the car running and system voltage up at 13.6V it
would charge. The thing to watch out for is that the
direct connection may give you a laptop chassis hard
tied to car ground, sparks or worse if you put it up
against the wrong thing. I have since found a little
inverter (forget where, probably AutoZone) which has
enough output to run my AC charger and this makes
the laptop isolated from the car, nice. Mine is a
Vector(R) VEC040 Pocket Power Inverter 70 Watt.
The PC power supply adapters I have show current
draw ratings of about 150W but this seems to be a
bit "sandbagged" and the little inverter has held up
OK so far (not even warm). 70W is about 6A @ 12V,
throw on some inefficiency and probably still under
10A on a 20A fuse. I have run the laptop off one
plug and the radar detector of the other w/o
popping one yet.
the battery itself. If the charger voltage is 15V then
you may be able to rig a straight plug. I did this on
the old Toshiba I was using and it worked fine; it
would not charge, sitting with engine off, but would
run off it without depleting the laptop battery; with
the car running and system voltage up at 13.6V it
would charge. The thing to watch out for is that the
direct connection may give you a laptop chassis hard
tied to car ground, sparks or worse if you put it up
against the wrong thing. I have since found a little
inverter (forget where, probably AutoZone) which has
enough output to run my AC charger and this makes
the laptop isolated from the car, nice. Mine is a
Vector(R) VEC040 Pocket Power Inverter 70 Watt.
The PC power supply adapters I have show current
draw ratings of about 150W but this seems to be a
bit "sandbagged" and the little inverter has held up
OK so far (not even warm). 70W is about 6A @ 12V,
throw on some inefficiency and probably still under
10A on a 20A fuse. I have run the laptop off one
plug and the radar detector of the other w/o
popping one yet.
