OpenSprinkler › Forums › Hardware Questions › OpenSprinkler Pi (OSPi) › Voltage staying high on station, valves not closing › Reply To: Voltage staying high on station, valves not closing
Your power adapter is clearly a DC adapter — it outputs 24V DC not AC (you can tell that because what follows from the 24V mark is a straight line, whereas if it outputs AC voltage it should be a wiggly line). Also, the label show polarity + / – and if it was AC it should not have polarity. This is the source of the problem. You must use an adapter with AC output voltage, not DC.