HOW TO: 12V Water pump relay powered by mains power?

Other Hardware General Electronics
1

Hi there,

This is my first Arduino project. I would like to water the pot plant on my balcony for approx 2 min every 12 hrs.
power source will be mains supply.
Will the bellow system work? do I need to be putting fuses somewhere in here?

System Diagram
ProjectWaterPump|690x280

Buck Converter:

Ardiunio Uno R3:

Water Pump:
Water Pump 12V Pressure Shower 4.3L/Min – Devanti

2

Rectifier:

Relay:

3

@llewy777

for approx 2 min

If you run that pump for 2 minutes you will be pouring 8.6 liters of water on your plant.
Maybe a much smaller pump would be better and cheaper.
Once you choose a new pump, then you can choose the right power supply.

Maybe this:

or

4

That should work. Wire and fuse size is dependent on the length of the 12V circuit.

You fuse to protect your wire. The longer the wire the larger the wire. If the distance from the "rectifier" to the pump is 4 meters or less use 16AWG and 10A fuse.

5

With 4A power supply for sure you don't need to replace that fuse...

6

Oh, I missed the 4A limit on the power source. 4A may not be enough to start the pump. The 6A version MIGHT work depending on wiring.
Consider the 10A version.