Covert to Watts, Input and Output Values provided, Covert it to Watts

AI Thread Summary
To calculate the wattage of the Sony laptop charger, the output voltage is 19.5V and the output current is 4.7A. Using the formula for power (W = V x A), the output power is determined to be 91.65 watts. The discussion also notes that the charger may consume additional power, which could affect overall efficiency. The symbols on the charger indicate that it operates with both AC and DC power. Understanding these specifications is crucial for assessing the charger's performance and compatibility.
raokhan
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I have this Sony Laptop, the adapter has the following specifications:

These are the input and output values of laptop charger.

19.5V written in bold on top
Input:100-240V~1.3A 50-60Hz
Output: 19.5V---4.7A, the dotted line also has straight line above it, I don't know what's that symbol called, can someone help me in calculating how much watts it is?
 
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welcome to pf!

hi raokhan! welcome to pf! :smile:
raokhan said:
I have this Sony Laptop, the adapter has the following specifications:

These are the input and output values of laptop charger.

19.5V written in bold on top
Input:100-240V~1.3A 50-60Hz
Output: 19.5V---4.7A, the dotted line also has straight line above it, I don't know what's that symbol called, can someone help me in calculating how much watts it is?

~ (as you know) means AC, and that no-overtaking double-line means DC :wink:

for DC, power (in watts) = volts times amps (W = VA),

so in this case the output power is 19.5*4.7 W :smile:

(but i don't know how much extra power is consumed by the charger itself :confused: … chargers can get rather warm!)
 
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