5V power adaptor + powerbank

Hello!

I'm working on a data logging temperature and humidity project and been thinking about powering everything up. I'll use a 5V(1A) power adaptor but since I'm going to put in a place that suffers from frequent power outages I thought that maybe I could use de usb port for a cheap 5000 mAh powerbank. Is it possible to keep it plugged into the electricity AND on the powerbank? I don't know if the Arduino UNO will give any priority to the power adaptor or if I'm going to fry everything up the moment I plug the powerbank.

Also, I've read somewhere in this forum that maybe powerbanks understand the low current draw from the Arduino board as leakage and just turn itself off. Does anybody here ever used powerbanks with an Arduino to confirm this info?

Hello!

I'm working on a data logging temperature and humidity project and been thinking about powering everything up. I'll use a 5V(1A) power adaptor but since I'm going to put in a place that suffers from frequent power outages I thought that maybe I could use de usb port for a cheap 5000 mAh powerbank. Is it possible to keep it plugged into the electricity AND on the powerbank? I don't know if the Arduino UNO will give any priority to the power adaptor or if I'm going to fry everything up the moment I plug the powerbank.

Also, I've read somewhere in this forum that maybe powerbanks understand the low current draw from the Arduino board as leakage and just turn itself off. Does anybody here ever used powerbanks with an Arduino to confirm this info?

eduardobio:
I don’t know if the Arduino UNO will give any priority to the power adaptor or if I’m going to fry everything up the moment I plug the powerbank.

Take a look at the datasheet. It’s all in there. You should be looking at U5A, T1, USBVCC and +5V.
If the voltage on Vin is greater than 6.6V, the USB power is turned off, and Vin is used as the power source.
Things are a bit different when you connect the 5V from the adapter directly. Current can now flow from the 5V pin into USBVCC and vice versa. That’s not what you want.

eduardobio:
Also, I’ve read somewhere in this forum that maybe powerbanks understand the low current draw from the Arduino board as leakage and just turn itself off. Does anybody here ever used powerbanks with an Arduino to confirm this info?

None of the powerbanks I’ve tried detect the Arduino as a load, and they all turn themselves off after a couple of seconds.

Pieter

I use a power bank to power five (5) 8x8 LED matrices and an Arduino Pro Mini.

I gave it to friends who go to fairs and such. It is a scrolling sign to draw attention to their table.

There is not a second source of power.

A 2200 mAH power bank can run the matrices and the Arduino Pro Mini for 12+ hours.

You can look here for a similar discussion. https://forum.arduino.cc/index.php?topic=497195.0

Get a powerbank that can charge and supply power at the same time. Usually the cheap ones without all the bells and whistles can do that (Hint, look for one with NO button)

Then the powerbank works like an UPS. I've done this numerous times - works fine!

// Per.

duplicate post at http://forum.arduino.cc/index.php?topic=534362.msg3642314#msg3642314

eduardobio: Also, I've read somewhere in this forum that maybe powerbanks understand the low current draw from the Arduino board as leakage and just turn itself off. Does anybody here ever used powerbanks with an Arduino to confirm this info?

Yes, that is expected behaviour.

A data logger application will normally use so little power that the powerbank will turn itself off.

It is alledged that there are some power banks that do not have this 'feature', no idea which ones.

srnet:

It is alledged that there are some power banks that do not have this ‘feature’, no idea which ones.

Hint: Look for one without any buttons to “turn it on”

Those have no microprocessor to control the boost-converter inside. I have a handful of these.

// Per.

This one : https://www.banggood.com/37V-Liion-Battery-Mini-USB-To-USB-A-Power-Apply-Module-p-928948.html?rmmds=search&cur_warehouse=CN would probably work, I have one but I'haven't test it yet!

Ciao, Ale.