OpenSprinkler › Forums › Hardware Questions › OpenSprinkler Pi (OSPi) › OpenSprinkler Pi Interfacing with relay board › Re: Re: OpenSprinkler Pi Interfacing with relay board August 21, 2014 at 5:10 pm #27880 RayKeymaster The current version of OSPi has per-station bidirectional TVS, which is used to suppress transient voltages. So you don’t need additional flyback diode anymore. The post you referred to uses a relay board, which has built-in flyback diodes.
