Two-Way Normally Closed Solenoid Valves

SUN’S Accumulator Dump valves will automatically discharge an accumulator whenever the pump is shut off, protecting maintenance personnel who may be required to work on the system.

Whenever the pump is started, the pilot-to-close check valve closes, blocking the discharge path to tank. The standard check valve prevents oil in the accumulator from back-flowing through the pump. When the pump is stopped and the pressure drops, the pilot-to-close check opens and oil in the accumulator is bled off to tank through a 1/8” diameter control orifice.

To assure proper operation, pressure at port “P” must be at least 60% of the accumulator/system pressure. For this reason, the valve is usually used in circuits with variable-volume pressure compensated pumps or in high-low circuits where the small volume, high pressure pump is kept operating continuously.