Renogy 20A dc to DC report
Hi All, Regarding the Renogy 20A DC to DC Battery Charger 12V, the unit puts out 20 amps, but draws 30 amps when doing so. This is the result of bench testing.
Forum Discussion
Lwiddis wrote:
That’s terrible efficiency! Thank you for posting.
Re read my post.
It looks bad, but in reality it isn't as bad as you may think.
If you use watts as part of the conversion you will notice that watts will be pretty much the same other than the switching power supply efficiency which can be as low as 85% and as high as 92%.
for instance 12.0V at 30A is 360W
If you convert to 14.0V at 360W you get 25.7A at the output not including the switching power supply loss of say 15% which would be about 3.9A, the result is 21.8A available at 14V...
Converting the voltage up drops the amps of the output but the watts stay the same. It is the principle behind why utility companies use massive transformers (which waste a lot of energy) to boost the power plant voltages up for transmission then convert the voltage down to your household voltages.. Without that conversion they would need to string even bigger more massive wires on the poles..
Does that help clear it up a bit?
