Power supply selection - 12v - multiple relays

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1

Greetings!

I have the attached project for a small homemade greenhouse automation.

(lease ignore the 4xAA power supplies in the project, I coudlnt find a 12v power supply in Fritzing diagram software...)

I'll be using at least 3 pieces of 12v devices. I have some options for a power supply I can't figure out if its harmful to use a single power supply for multiple devices connected to a 4x12v relay board or not....

Devices:
1- 12v car kettle for heating. I couldnt find specs but im guessing should draw around 4amps
2- A peltier rig for cooling. 12v around 4amps
3- RS360SH water pump. 12v - 4.5 amps
4- A small 12v humidifier

One option is to buy three 12v - 5A power supplies and hook them up as in the diagram....

The other is to buy one 12v - 29A 600W ( FX600-W1V12) power supply and use that with with a 4 x 12v relay board...

Which one would you go with for this project?

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Separates - then you don't need so much 12V power running around, just some simple low current AC extension cords.

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1- 12v car kettle for heating. I couldnt find specs but im guessing should draw around 4amps

4 Amps x 12V is only 48 Watts, which isn't a lot of heat. I'm guessing it takes more... If you've got a multimeter, measure the resistance and calculate the current (Current = Voltage/Resistance).