Pins melt with 12v fans

Other Hardware General Electronics
1

Hi people,

I'm trying to control 4 fans depending of some conditions.

My components are 4 power supplies (12v 5a) and 4 fans connected to 4 relays on a protoboard ( and sensors, extensions of wires etc.)

The positive wires of fans and power supplies stay connect to each relay. The negative of fans and negative of power supplies stay connect on a protoboard beside GND of Arduino (inline). Once started, the GND pins get heat and melt quickly. :o

Some idea about what happening or what i need check?¿ Thank's

2

Please post links to all the components, and a hand drawn wiring diagram.

Protoboards are intended for low power logic circuits, LEDs etc. The tracks will burn if you try to use them for high current devices like motors.

3

jremington:
Please post links to all the components, and a hand drawn wiring diagram.

Protoboards are intended for low power logic circuits, LEDs etc. The tracks will burn if you try to use them for high current devices like motors.

A quickly diagram => diagram_aifc.png - Google Drive

4

(12v 5a) and 4 fans

20 Amps is "a lot".

The ground for each fan can go directly to its power supply and in this set-up the fans don't need a common "system ground".

(The control/coil side of the relay board does need a connection to the Arduino ground.)

5

DVDdoug:
20 Amps is "a lot".

The ground for each fan can go directly to its power supply and in this set-up the fans don't need a common "system ground".

(The control/coil side of the relay board does need a connection to the Arduino ground.)

Do you mean that i need connect the GND of a fan directly to GND of a transformer?¿

So.. if i want apply a big power supply (12v 20a) instead four individual supplies... What is the correct way for connect?

Thank's

6

What is the correct way for connect?

Use suitably heavy wires and solder the connections.

7

DVDdoug:
20 Amps is "a lot".

The ground for each fan can go directly to its power supply and in this set-up the fans don't need a common "system ground".

(The control/coil side of the relay board does need a connection to the Arduino ground.)

Ok, i think that it works. I'll run this a long time for test how works. Very thank's!