Without taking the adapter or laptop charger apart, it can be difficult to tell externally why the laptop charger has stopped working; it could be as a result of lose internal wiring but either way, you need to replace it so you can continue to charge and use your laptop. Buying the right laptop charger is crucial.
The information you need to get the right adapter are:
i. Voltage and amperage:
To get the right laptop charger, you need to know the electrical power required by your particular laptop model. Generally, this information is on the underside of your laptop; voltage is also known as ‘volts’, and is symbolised by the letter ‘v’. Amperage is also known as amps, and is symbolised by the letter ‘a’. If you have your old, non-working adapter, you will probably find this information on it.
ii. Wattage:
Older laptops (and some newer models) will only have the wattage (that is, watts) on it, for example the charger might say 65W. Wattage roughly equals the voltage multiplied by the amperage
e.g. 18.5v x 3.5a = 64.75w, rounded up to 65w
** important
The voltage of your new adapter must be within – or + 5% of the volts needed by your laptop! **
An example:
if you laptop required 18.5v as in the above example, the charger should be a minimum of 17.5v and a maximum of 19.5v,a relatively small margin of error.
Matching the amps is less important; as long as it matches or does not exceed more than double the laptops amp needs, it should be OK to use. The laptop will only draw the power that it needs to use.
An example:
Using the above example, the maximum amperage value on the new adapter would be 7a but no less than 3.5 amps.
iii. Connector sizes:
Clearly, the connector needs to be the right size. Manufacturers tend to create ‘tips’ that are standard for certain models so if in doubt, consult the laptop manufacturer. A quick search on the internet will be useful, as manufacturers will give you dimension for the tips pr pins online.
In summary, the right laptop adapter is:
… when the voltage is within plus or minus 5% of the laptop’s power requirements. If you use a charger with too high or too low a volt rating it could damage your laptop.
… when the amperage of the charger is the same – or higher – than your old adapter, but it cannot be lower in amps than the previous adapter as your machine will not work correctly.
… when the connector is the right size.
Other sensible advice would be to buy the adapter in the country you intend on suing the machine most. Sounds a bit obvious, but we so many people chopping on the internet for bargains, buying replacement laptop chargers from Hong Kong might be cheaper than buying one in the UK. Power supply is different between countries and so getting the wrong one can cause damage.
Safety marks should also be visible on trusted brands and these will provide various protective measures such as ‘over voltage’, short circuit and over current. These protective measures will stop your laptop overheating, a common problem with some laptops.
And finally…
If you laptop charger is under warranty, and has stopped charging your laptop then contact the manufacturer for a replacement; don’t spend money if you don’t have to!
