# What kind of power do i use for this arrangement?

Hi There.

I am working on a project in which Arduino Mega 2560 is connected to 2 Animal Repeller Devices, each needs 6V power and around 200mA current. For now I am planning to operate these devices on normal Power Outlet but i am planning to deploy this project in a remote area so i need some other form of power (battery or may be solar power). If i do simple maths, here is what i need

Arduino = 12V (40mA)
Repellers = 6V + 6V= 12V (200mA +200mA = 400mA).

So total voltage and current i ll be needing is 24V and 400mA. I need to power up Repellers through Arduino, meaning if some condition is true only then Arduino will power up the Repellers.

I need advice on how to power up this arrangement and what kind of power (Batter or solar) options do i have?

Arduino = 12V (40mA)
Repellers = 6V + 6V= 12V (200mA +200mA = 400mA).

do you know that arduino can be powered from as low as 7vdc to a max of 12vdc. since its going to be a mobile setup, why waste your precious power giving the arduino 12VDC.

the repeller part when you say 6 v +6V it means your hooking it up in series. but then when you did the current calculation, it means that your hooking it up in parallel. so which one is actually your setup?

The main idea is to control Repellers through Arduino, so current should be given to Repellers only when Arduino checks for some situation to be true. I would love to save the power and make my devices use less power wherever necessary.
As for using repellers in parallel or serial, i actually wrote there are two repellers in this arrangements, thats why i used 6+6, its nothing to do with serial and parallel. I am actually interested in knowing what kind of power will be ideal for this arrangement where 2 different repellers are connected to Arduino device?

All you need is a single supply providing 6.5 to 7V and capable of supplying 500 mA or more. This can drive the Arduino and both repellers. If you are worried that this is a little too much voltage for the repellers, you can connect a silicon diode in series with each one to reduce the voltage by around 1V.

dc42:
All you need is a single supply providing 6.5 to 7V and capable of supplying 500 mA or more. This can drive the Arduino and both repellers. If you are worried that this is a little too much voltage for the repellers, you can connect a silicon diode in series with each one to reduce the voltage by around 1V.

Thanks for the reply, that was very informative. Let me try the arrangement and i ll get back.

Or even a 6V accumulator with a LDO 5V regulator to power the Arduino. So 6V at 40mA if repellers are off, 440mA if on. Use a logic-level MOSFET perhaps to switch the repellers on/off. If using battery power you can sense the battery voltage via a resistor-divider to detect when its going flat (lead acid batteries are completely intolerant of over-discharge and will be wrecked if you let this happen).

If you know the proportion of time the repellers will be on it means you can estimate the average current drain and get a good estimate of
the battery capacity needed. Lets say "50% of the time" and you want it to run for 1 week, thats 168 hours at 0.24A, or about 40Ah. Since batteries lose capacity with age you'd then double that to 80Ah for a realistic value. 6V 80Ah is about the size of a car battery.

If the repeller is only going to be on for a small percentage of the time it will be worth going to a bare-bones Arduino and using sleep-mode
to reduce the average current and get more battery life per unit-capacity.