Have you ever wondered how efficient your phone or laptop charger is?
If you look at the tiny writing on the charger it gives you a few numbers that help you work it out.
They look a bit like this:
To work out the efficiency, you’re looking for the input voltage, input current, and output voltage and output current, highlighed in yellow above.
The input voltage might be in mA (milli-Amps), so to convert that to Amps, simply divide by 1,000.
In this case, both input and output currents are in Amps, so can enter the numbers as they appear.
For this one, the input voltage is a range (100-240V), so you can enter that range directly in the Livesheet (as has been done by default in the form below).
Try entering the numbers for some of yours and see how they look.
I’ve found that 25% seems to be fairly typical.