Nelson Irrigation Corp. 848 Airport Rd. Walla Walla, WA 99362-2271 USA Tel: 509.525.7660 Fax: 509.525.7907 E-mail: [email protected] Web site: www.nelsonirrigation.com
Control Valve
Application
Guide
4.2 HOW THE VALVE RESPONDS TO THE CONTROLS
Figure 4
Solenoid energized
The upstream water is blocked.
The sleeve chamber is vented to
the atmosphere, the flow of the
valve is open.
Solenoid de-energized
The upstream water is applied to
the sleeve chamber. The flow is
closed off by the sleeve against
the center seat.
SOLENOID
CONTROL
HOW PRESSURE CONTROL WORKS
10
PRESSURE
REDUCING
CONTROL
Pressure lower than
control set point
The pressure regulating control is temporarily
out of balance. The sleeve chamber pressure
is opened to vent to the atmosphere.
Pressure same as
control set point
The pressure control is in balance.
Pressure higher than
control set point
The pressure regulating control is temporarily
out of balance. The sleeve chamber pressure
is opened to upstream pressure until the set
point is reached.
