# Powering Wireless RFID Bird Feeder

Thread Starter

#### rmady

Joined Oct 3, 2018
5
Hello, I am trying to power an RFID bird feeder that has 3 components: battery supply, circuit board, and antenna. The battery supply connects to the circuit board (type = Arduino) and then the circuit board communicates to the antenna.

I am having trouble powering the board. The board requires 5V input. I am using a 14.4 V 3Ah NiCd battery pack and then using this to reduce the voltage to 5V. I soldered the battery to the converter to the board. It only powers the board for a little over 2 days (which is way too short. I need it to last 4-5 days). I also have this to try out as well.

Essentially I'm new to this world of electrical engineering and don't really know what I'm doing. The two links I provided look equivalent to me, but maybe they aren't.

I need a way to power the board for 4-5 days so any help in figuring out the best way to do this would be great!!
Thank you, Thank you!

#### Sensacell

Joined Jun 19, 2012
3,442
Use a bigger battery -OR- re-write the code to use the power more efficiently.

Thread Starter

#### rmady

Joined Oct 3, 2018
5
Use a bigger battery -OR- re-write the code to use the power more efficiently.
Unfortunately I don't know how to code for it so I guess a bigger battery. And by bigger you mean a higher voltage?

#### Sensacell

Joined Jun 19, 2012
3,442
More energy capacity - Watt-Hours

Thread Starter

#### rmady

Joined Oct 3, 2018
5
More energy capacity - Watt-Hours
So a higher voltage? Or a higher Ah?

#### Sensacell

Joined Jun 19, 2012
3,442
So a higher voltage? Or a higher Ah?
Assuming the battery has the same terminal voltage, then yes, more Amp-Hours.

If you increase the voltage, (assuming your switching regulator can tolerate it) with the same value of AH, you would get more total Watt-Hours too.

#### Dodgydave

Joined Jun 22, 2012
11,301
You need to measure the current that the rfid is using, then you can work out which battery to select.

#### MrChips

Joined Oct 2, 2009
30,792
I have designed and built environmental monitors that run for longer than two years on a single alkaline battery.

You are starting out on the wrong premise and the wrong approach.
Arduino is not designed to be energy efficient.

You need to conduct an energy audit by measuring the current and voltage required by all devices. When programmed properly, microcontrollers can be placed into sleep mode that consume less than 1 microamp.

Thread Starter

#### rmady

Joined Oct 3, 2018
5
Assuming the battery has the same terminal voltage, then yes, more Amp-Hours.

If you increase the voltage, (assuming your switching regulator can tolerate it) with the same value of AH, you would get more total Watt-Hours too.
Thanks for continuing to help me out I am limited by space by a container the battery goes into, so I ordered a 12 V 9Ah battery to try out.

I have designed and built environmental monitors that run for longer than two years on a single alkaline battery.

You are starting out on the wrong premise and the wrong approach.
Arduino is not designed to be energy efficient.

You need to conduct an energy audit by measuring the current and voltage required by all devices. When programmed properly, microcontrollers can be placed into sleep mode that consume less than 1 microamp.

Thanks for your response! Unfortunately, I am trying to work with what I have. I don't really have an option to use anything other than the Arduino board that I have (I don't know how to build an RFID capable board unfortunately). With that constraint, any suggestions?

You need to measure the current that the rfid is using, then you can work out which battery to select.
How would I do that?

#### MrChips

Joined Oct 2, 2009
30,792
With the given constraints, you can use a car battery, a sealed lead acid battery, or a long AC extension power cord.

Thread Starter

#### rmady

Joined Oct 3, 2018
5
With the given constraints, you can use a car battery, a sealed lead acid battery, or a long AC extension power cord.
I think I am limited to a sealed lead acid battery because the car battery wouldn't fit in the container.