davidcoton wrote: ↑
Tue Jan 14, 2020 5:25 pm
I think the figures are correct. 120mW is for a Pi4 HALTed (and 3V3 powered down). From your description, yours may be HALTed, but 3V3 is still active. Read the rest of this thread for an explanation (POWER_OFF_ON_HALT setting).
I read about it, but the PI2/PI3 deliver 3V3 while they switched off and the powermeter shows 0.0W.
If you make a Table you should be take the same conditions for all Pi´s.
The PI4 powers 3V3 cause extern board could get defective, cause they not build for it and on any other PI
3V3 stays after shutdown. Cause keeping 3V3 is the default, and the PI4 seems not able to keep GPIO 3V3 while
switching the other parts off.
PiTommi wrote: ↑
Thu Jan 16, 2020 11:57 pm
I have seen people having custom devices plugged between the Pis USB and the PSU output but not sure exactly what to do. Anyone having a recommendation or what would you do?
A power meter for 230V is about +-0.2W, some +-0.6W and some +-0.1W. This result is with the power that
the PSU take for itself. The efficency is about 76-90% depending on the PSU Model.
The devices between PSU and USB are power meters for 5V, they are usual at +-0.5%. You get them on ebay.
If you dont want to buy one you can take the Voltage and then Ampere with a usual Multimeter and multiply the one
with the other to get Watt.