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65w and 90w AC Adapter

Last response: in Components
April 1, 2011 2:35:39 AM

My Laptop uses a 65w AC Adapter but recently I recharged it with a 90w Adapter. Now when I try to use the 65w adapter it does not recharge the battery. Is there a way to reconfigure my laptop to where it will charge using the 65W Adapter my Dell Inspiron 15 Laptop came with?

More about : 65w 90w adapter

a b ) Power supply
April 1, 2011 5:36:36 PM

There's more to this than 65W vs. 90W. If that had been the only difference, you would not be having a problem. In selecting a charger unit, you need to make sure several items match up:
1. Is the charger unit supplying AC or DC to the laptop? MUST be same as specified for the original charger.
2. Type of battery in the laptop. Many chargers are designed for a particular battery type and supply exactly the right voltage and charging rate (current) for that. Some even are "programmed" to alter the charging rate depending on the state of the battery's charge. All have a limit on the battery's maximum voltage to avoid over-charging. All of these are important, and that's why using the wrong charger can cause trouble.
3. Polarity of the connector - MUST be the same as original.
4. Voltage MUST be the same.
5. Wattage MUST be at least as much as the original charger, can be higher without problems.
6. Max amps must be at least as much as the original, can be higher.
7. Connector on the end of the charger cord - must be the same size pins and spacing so that it fits the connector in your laptop without damaging it.

From your description, at least one of these was not right. Mis-matching some of them can cause permanent damage to your machine. Some others may merely cause a minor problem (like bent connector pins) that you may be able to see and fix.
April 2, 2011 2:25:04 AM

Both Chargers are Dell AC Adapters but when I look on the back of the Laptop it says Adapter should be for PA-21 or PA-3E Family. The Adapter that came with my Laptop is a PA-21 65w AC but I charged with a PA-10 and its just says "Maximum Output Power 90W." The input (100-24V) and output (19.5V) both read the same on the Adapters. The Connecter at the end of the cord is different. The original (for a lack of a better desription like an "Octagon") and the one that is the PA-10 that now is the only one that charges the battery is "Round." So here what I got:

1. Both are AC
2. The Family type is not compatible or not specified to use
3. Polarity of the Connecter....Sorry, not sure of that
4. Voltage is the same
5. Wattage is the same
6. Max Amps do not seem to be an issue
7. The end connecters are different

DO you think it might be the connecter pins because the computer "SEEMS" to be running fine. I just don't get a charge out of my original adapter. It will owrk when its plugged in, it just wil not charge. If is the pins, can I fix myself or do I need to take it somewhere? Thanks for your assistance.
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April 2, 2011 5:31:27 AM

It did come on. Should I shut down and restart w/ the battery?
a b ) Power supply
a b D Laptop
April 2, 2011 3:29:10 PM

First Paperdoc did an outstanding explanation.
On wattage, in essence it the point at which additional current will cause the output voltage to decrease - also if current exceeds the rated value the Adaptor could heat up excessively. So generally using a higher wattage adaptor is not an issue, as long as other factors are the same.

Generally the control circuit for charging the battery is inside the laptop. Most laptop chargers, if for Li-ion are 19 Volts and list the current (ie my Toshibia - 19 V @ 3.98 A, approx 75 W). But this voltage must be reduced as the typical battery voltage is 10.9 V
(3.6 Volts per cell) In my case I use the same adaptor for the 6-cell battery as I do for the 9-cell battery pac.

My guess - I think you aready know, is that you have damaged the jack on the laptop as you ask about replacing. This depends on (1) your ability to disassemble and your skill using a soldering iron. and of course obtaining the new jack.

?? sinse you already have probably damaged the jack/plug connection, why do you need to go back to the orignal adaptor, if the higer rated one works.

?? Is your plug/jack the 4 pin, or is it just the single male/female type.