There seems to be nothing in the manual about how to connect a pump to the bhyve even though it obviously has a connection. Similarly there are no details on connecting the sensor. Is there another more detailed manual than the one that came with it?
You need to connect a 24V coil relay to the pump connection and the common (ground) connection. The relay should be rated to handle the load of your pump. connect the sensor to the sensor terminals (remove the jumper first). I found that the sensor requires a decent rain before it triggers the unit not to allow watering, so don’t be surprised if you see it watering while it is raining.