Connecting arduino to battery

[iuliana_ast]

I want to power up an Arduino UNO board independent of USB/laptop. I need to power it up from battery. I serialized 3 batteries 1.5V each, which results in 4.5 V, but the board won't light up. I connected the + from the serialized batteries to the VCC and the - to GND, but the it isn't working. Any ideas on how to power the board?

I attached the current connections of the Arduino. Apart from the batteries, I have 2 leds, connected to pins 2 and 4 and a DHT22 sensor connected to the 3rd pin.

[ruilviana]

@iuliana_ast

I connected the + from the serialized batteries to the VCC

Hi
When you say :
"I connected the + from the serialized batteries to the VCC"
do you mean the 5V pin or the Vin pin of UNO?

[iuliana_ast]

The 5V pin, sorry about the confusion

[red_car]

Do you have anything else connected to the Uno?

[killzone_kid]

have you measured what you get on +5v and GND after you connected the battery?

[iuliana_ast]

I attached the photo to the post

[iuliana_ast]

@killzone_kid

and GND after you connected the battery?

No, I don't have a multimeter at hand...

[killzone_kid]

all the batteries or any one of the batteries could be dead, there might be bad connection. You need multimeter, you need it in general not just for this project but if you want to poke at electronics

[iuliana_ast]

to test the connection, will I burn the Arduino board if I use a 9V battery instead of the 3 of 1.5V?

[ruilviana]

Hi
If you connect to 5V, yes it will burn.

[red_car]

Those batteries look like they are connected in parallel not series. That is, you will be getting 1.5v not 4.5v.

You need them connected like this...

[iuliana_ast]

thank you, I'll try that. I managed to get a hold of a multimeter and the issue is that the battery shows 1,5V, but the wires at the end of a battery show 0V... I don't know how to set the wires properly

[red_car]

@iuliana_ast

I don't know how to set the wires properly

Like in the picture above...

[iuliana_ast]

I tested the voltage of only one battery through connecting the wires to the + and - and I get 0V. This is what I mean when I say I don't know how to set the wires to show 1.5V on the multimeter

[red_car]

Show a picture of what you are doing... are you sure the wire you are using is ok?

[iuliana_ast]

Not sure if it is visible what I'm doing, I tried connecting the batteries like in the picture you showed. Also, I measured the green and yellow wires in the right and they show 1.5V after doing the series connection.

[red_car]

Impossible to see what is happening in that picture. You should just tape the 3 batteries together, end to end... make sure they are touching. Then just have a single wire from each end... like this

Or like this... which is the same electrically speaking

[iuliana_ast]

You just solved my issue, I cannot thank you enough! It's working