I am a total newbie in the world of Arduino, so bare with me please. I've been trying to build a simple project based on a Youtube-series. I'm using the UNO + Motorshield to power and control 2 PC fans that are managed via a custom software program (Simhub).
The project has the following components:
- Geekcreit R3 UNO
- DK Electronics Motor shield
- 2x 12V 4000RPM pc fans
- 12V 3A PSU
The fans have the following specs:
- 4500 RPM
- 1.52 Current (A)
- 12V (DC)
- 18.24 Power (W)
The builder in the Youtube clips suggests using a 12V 3A psu. So I first tested the psu out on my UNO to see if it worked. It sure did, but about 1 minute later the main fuse popped on the UNO and the board is in limbo. I had the UNO connected via USB as well, so I'm guessing that wasn't the smartest move on my part.
After getting a new UNO I rebuild the boards and tested everything out with a 12V 500mA connected to the ext power supply of the motorshield. Hoorah, 1 fan works! It only blows very lightly but it works. The 2nd fan doesn't want to activate on any of the M2/M3/M4 slots. I suppose this is because of the low amps of the psu (500mA)?
Now I want test out the 12V 3A psu on the motorshield, but I'm scared to blow that one up as well. I connected it for 3 seconds I instantly heard a 'sizzling' sound and the smell of burning electronics. I disconnected it immediately and tried it out again with the 500mA psu and luckily it stills works.
So... My question to you experienced UNO builders is: is it safe to connect a 12V 3A PSU to the DK motorshield? Or is this too much? And what PSU would you guys recommend to power the 2 fans? I don't need them to be working at 100% full power, but somewhere around 80% of their capacity would be nice.