I am working on an arduino project in order to control 5 shutters (with 2 buttons OPEN/CLOSE I want to open/close contemporary all the shutters). I bought a relay board (the one with 8 relays you can find on ebay) but I am not sure it's ok because a relay got broken (it remained excited end so the shutters was mainteined in the up course until I disconnected the cable).
Did I have to take some precautions?
Details in the project description: OTHER PROJECTS

Thanks a lot