I know that you have to place a diode in parallel with a relay to use with i/o on microcontroller. Would you have to do the same with a relay board such as......
https://www.sainsmart.com/module/acceleromete/arduino-pro-mini.html
**broken link removed**
https://www.sainsmart.com/module/acceleromete/arduino-pro-mini.html
**broken link removed**