The OA6-24 control board is designed to control multiple 24vac solenoid valves. It provides an easy and efficient method to control up to 6 valves… each with individual timer settings. Up to 5 OA6-24 can be connected to a single Aqua-x providing a maximum of 30 individually controlled outputs to connect to your solenoid valves. The Aqua-x can also provide a “master pump link” by using a DSP-1 along with the OA6-24. Connecting a DSP-1 to the OA6-24 provides an automatic “pump link” between the DSP-1 and the OA6-24. When any of the 24vac irrigation zones are activated on the OA6-24, the DSP-1 will automatically turn on the pump.