Cla-Val Pacific's Series 131 and 631 Electronic Control Valves are designed specifically for applications where remote control of valve function is preferred. They are hydraulically operated, pilot controlled, diaphragm valves. The solenoid pilot controls are actuated by electrical signals from the VC-22D Electronic Valve Controller. The solenoid pilots either add or relieve line pressure from the cover chamber of the valve, causing it to open or close as directed by the electronic controller. Use this valve for applications where water containing unacceptable levels of chemicals is blended with clean water to achieve compliance with State and Federal regulatory requirements.