PowerBlock & Raspberry Pi power warning

[neolith]

Hi,

I am trying to use the PowerBlock to power a RPi3 and a small screen. I connected my power supply to the PowerBlock's 5V input and the 5V output to the screen. The PowerBlock sits on the RPi. Everything seems to work fine except for the fact that the Pi is constantly showing the little yellow lightning.

According to my multimeter 4.8V reach the PowerBlock and about 4.5V reach the screen. So my first guess would be that my power supply is insufficient even though it should provide 5V. Could that be the case? And if it is and I need to buy a new one, is there anything I can look for to make sure it does provide enough power? Also What is the max V/A that a power supply should have to run the PowerBlock this way?

Any help would me much appreciated. :)

[emclinux]

What's the amp rating on your power supply? How many amps does your screen draw?

For example, I tried just the rpi3 on a 1A and 1.5A power supplies and both caused the lighting bolt and went away when I used a 2A. These were cheap power supplies with things like controllers and USB drives plugged in so a I know the specs say 1A but your extras and quality of power supply can come into play. I would suggest if you can see how many amps you are pulling with your multimeter or get a better power supply with more amps available.

[neolith]

Thank you for your reply! :)

The power supply should be capable of 2.5A and 5V, but since the voltage already seems to be off I don't have too much faith in it. Concrete info for the screen is a little hard to come by since it's from China, but I've found a distributor claiming that 1A is enough for the screen and its driver board. I'll take my own measurements this evening and look for an alternative power supply.

Thanks again for your help!

[neolith]

I got everything working flawlessly with a different power supply: 5.2V, 3A. :)