| Author |
Message |
RotorMotor2
Joined: 23 Nov 2006
Posts: 11
|
 Posted:
Thu Nov 23, 2006 6:08 am Post subject:
LAPTOP Amps and Watts and Volts |
|
|
ok, I have a HP laptop ze2000 or something like that and i want to use it in my car without getting an inverter to jump the cars 12v up to 110v so i can plug in my laptops AC charger only to jump it back down to the laptops required voltage.
on the back of the AC wall charger it says for the output:
18.5v 3.5a 65w
so i went looking for a simpler car charger on e-bay and found this:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=320049602097&ssPageName=STRK:MEWN:IT&ih=011
which is a 70w max charger that has multiple settings and 18.5v and 3.5a max is one of the settings, so i bought it.......
when i recieved it today it is the wrong one and i want to know if it will work without harming my laptop or overcharging my battery or overheating it or the laptop.
The one i recieved is a 80w max 4a max and only 18v or 19v options not 18.5v
what is watts and amps and voltage in lamens terms? watts is how much is available and amps is what the draw is and volts is the level? kina?
should i return this for the correct one in the e-bay link above?
thanks in advance,
Jeremy
|
|
| Back to top |
|
 |
neon
Joined: 25 Feb 2006
Posts: 570
|
| Posted:
Thu Nov 23, 2006 3:58 pm Post subject:
|
|
|
| Can you ruin your laptop NO is it substainable 80W but you may burn up your supply source it say max 4 amp which is fine but for how long. 80 watts is fine too 18-19v is no problem either stick a 10 amp diode in series and you will get your 19- diode drop of .7v . and the charger 18.5 v is probably a nominal voltage anyway,. IF i was you i would have bought a 12v dc to 22v dc and regulate it to 18.5v that would be much safer without worry. |
|
| Back to top |
|
|
RotorMotor2
Joined: 23 Nov 2006
Posts: 11
|
| Posted:
Thu Nov 23, 2006 6:08 pm Post subject:
|
|
|
well it is one of those universal adapters where it can go up to 24v but it says for 22v & 24v the amps are 3.3a and for 15v 16v 18v 19v & 20v it is 4a and the whole charger is 80w,..... Amps are used on demand right? like the more power my laptop uses the more amps it will pull? up to the limit of the charger? that is why i wanted to match the specs of the factory charger (see above) are watts steady? always 80w? or how does that work? (please see the details above)
|
|
| Back to top |
|
|
RotorMotor2
Joined: 23 Nov 2006
Posts: 11
|
| Posted:
Sat Nov 25, 2006 8:24 pm Post subject:
|
|
|
so if my regular adapter supplys 3.5a and my new dc to dc adapter does 4a and 80w then why might it burn up? it sounds like it is stronger than my ac to dc converter that only does 3.5a and 65w.......
so am i worrying too much about this or what? can i just set my new dc to dc converter to 19v @ 4a and 80w and just plug it in? my laptop and its battery is what i am most worried about and then second being heat generated from the converter because it is going to be permenantly installed in my car near carpet and pad......
see first post for the link to the converter i am talking about.
anybody? opinions appreaciated. |
|
| Back to top |
|
|
neon
Joined: 25 Feb 2006
Posts: 570
|
| Posted:
Sat Nov 25, 2006 9:21 pm Post subject:
|
|
|
| Understand this nothing in your car is stronger or weaker . What you must understand is load requirement. Your laptop require 3.5 amps at a certain voltage. A converter of 50 amps @xxx volts will work but a converter of 3 amps @xxx volts will burn out. now power is 15 x 3.3 amps=50w but the max total is 80w so at the 20 v you may drain 80-50=30w or 20v at 1.5 amps max.you cannot exceed 80 w total power. like 15v at 3.3 and drain 20v x 4amps at the same time reduce 15 and increase 20v or viceversa for a total of 80w. try connect to 18v and see.it should work and porbably will work safely with 19 v. make sure you are reading it corectly AC is not the same as DC |
|
| Back to top |
|
|
RotorMotor2
Joined: 23 Nov 2006
Posts: 11
|
|
| Back to top |
|
|
neon
Joined: 25 Feb 2006
Posts: 570
|
| Posted:
Sun Nov 26, 2006 12:27 pm Post subject:
|
|
|
| my VERY LAST REPLY w=volts x amps 18vx4amp=72watts power now if the power supply is 80w total it means you may totaly dissipate 80w using the formula above. Now get all the voltages out that you want and all the amps that you want BUT do not exceed the 80w limit. A 100 amp gen is great don't ever need to replace it except if faulty. buy yourself a meter $4 harborfreight.com put the meter to read amps current in the highest range disconnect [+] connect red lead to battery terminal negative goes to the fat cable now whatever you read on meter is your load drain turn on all your cadgets one at the time and and repeat ADD them all up for total amps drain. connect your solar panel and performthe same test on the solar panel then you will know wether the panel can handle the charging. i still think you worry for nothing a the solar will not work during the night so drain will occur during that time. |
|
| Back to top |
|
|
|
|
|
|
FAQ
Memberlist
Register
Profile
Log in to check your private messages
Log in
