Relay Control Board

The team purchased some relays from AllElectronics.com and we needed a board to control the 12 volt coil DPDT relays using a 5 volt signal line from the Arduino.

The electrical team decided to use 2 NPN transistors per relay:

  1. To control the power to the coil
  2. To control the power to the output(s) of the relay


We first tried mounting the relays and transistors to the Arduino shield board, but quickly ran out of physical board space.

Next we tried using a blank PCB from RadioShack and this venture proved to be more successful.