The picture shows the Raspberry Pi and my carrier board.
![Feature Overview of Carriar Board Feature Overview of Carriar Board](https://cdn.hackaday.io/images/7329651664581149902.jpg)
The main features of the carrier board are an RS232 driver, a fan header and the power supply.
Fan Header
Although the case lets lots of air inside, the CPU gets warm up to 50°C in idle. The fan can be controlled by the RPi via a GPIO. I set up a program which starts after booting the OS. It reads the CPU's temperature and sets the fan speed so, that the CPU's temperature is 35°C..
Power Supply
+5V power is provided by a closed frame power supply which can source a current of 3A which is plenty for the Pi. The supply can be completly separated from mains voltage via a switch, so no standby power is drawn. Additonally main voltage is passed through the switch to a second connector, which in turn is used to power the monitor.
![](https://cdn.hackaday.io/images/601061664582256610.jpg)
![](https://cdn.hackaday.io/images/6097871664583422867.jpg)
So after powering down the RPi, power can be disconnected from workstation and monitor by just one switch. Also just one flip of the switch turns on the hole system.
PCB
A view of the nacked carrier board.
![](https://cdn.hackaday.io/images/9929401664583085146.jpg)
The closed frame power supply is screwed onto the pcb. Short wires are soldered into the pcb and connect the screw terminals of the power brick.
![](https://cdn.hackaday.io/images/9456201664583645967.jpg)
![](https://cdn.hackaday.io/images/3998611664583743885.jpg)