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Topic: External power suply not working please help. (Read 363 times) previous topic - next topic

rbezan

Hello

I have a small problem:
I'm using arduino uno with atmega SMD chip and 2nd board (ethernet + sd card shield)
When it is connected to the USB it works normali, but when i connect to the 9V battery the led only flashes onece and thats it. i have tried connecting 7.5V, 12V, to the vin pins 6V and 5V but nothing seemes to work.

When i connected the 9V batteri via the jack and mesured the voltage on the 5V pins it vas around 1.6V. If i remove the ethernet shield it works normali on the battery.

I mesured the voltage on the ethernets shield regulator and it vas on the "in" lover than 3V and out vas 1.2V.


Does anyone have ideas?


Please for help.


Paul_KD7HB

Did you measure the ACTUAL voltage on the battery terminals when they were plugged in?

Paul

rbezan

Yes i have:
the 9V battery was actualy 3,15V with load (9,34 without load)
so i tried with a power suply:
settings on 9V :
with the load 3,30 V  (without load: 10,47V)

load - (connected to the arduino UNO and ethernet shield)

Paul_KD7HB

Yes i have:
the 9V battery was actualy 3,15V with load (9,34 without load)
so i tried with a power suply:
settings on 9V :
with the load 3,30 V  (without load: 10,47V)

load - (connected to the arduino UNO and ethernet shield)
And there you have answered your own question. The current needed by your project is way beyond what the batteries or the power supply can deliver.

Paul

rbezan

hm... i have read about it but thought that the power suply should work because in theory it should be capable to send 0,5 - 0,75mA of current.

I will try with a stronger power suply than.

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