Nelson 800 Series - User Manual

Nelson Irrigation Corp. 848 Airport Rd. Walla Walla, WA 99362-2271 USA Tel: 509.525.7660 Fax: 509.525.7907 E-mail: info@nelsonirrigation.com Web site: www.nelsonirrigation.com
VALVE CONTROL FUNCTION:
The PRESSURE REDUCING MANUAL ON-OFF model of the 800 Series Control
Valve is a hydraulically operated sleeve type valve with a pressure
reducing pressure control kit and a manual on-off. The flow through
the valve is controlled by a rubber sleeve which is actuated by
hydraulic pressure. When the selector is pointed to the "AUTO" position
then the valve will automatically reduce a higher inlet pressure to a
constant lower downstream pressure. The pressure reducing control
is adjustable to give a constant down stream pressure even with
fluctuating upstream pressure. The manual selector is used to
manually open or close the valve. Pointing the manual selector
handle to "OPEN" or "CLOSE" will override the "AUTO" control. Pointing the
Manual Selector handle mid way between "OPEN" and "CLOSE" will
hold the valve partly open.
The information on this sheet is for the
PRESSURE REDUCING MANUAL ON-
OFF control function with plastic tubing and internal or external filter
option (items D2 - D4, D12-D13, E1, H2 - H3 control function on
the VALVE SELECTION GUIDE apply to this sheet).
800PR5
800 SERIES CONTROL VALVE — CONTROL FUNCTION and MAINTENANCE
PRESSURE REDUCING MANUAL ON-OFF
D
MANUAL
SELECTOR
INTERNAL
FILTER
PRESSURE
REDUCING
CONTROL
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Summary

Valve Control Function

Manual On-Off Operation

Details how the manual selector controls the valve's open or close state, overriding auto mode.

Pressure Reducing Control

Explains how the valve automatically reduces higher inlet pressure to a constant lower downstream pressure.

Troubleshooting Guide - Valve Not Closing or Opening

Valve Fails to Close

Checks for leaks, tube 'U' flow, and filter blockage when the valve is in the 'CLOSE' position.

Valve Fails to Open or High Pressure Drop

Checks for blockages, adequate upstream pressure, and water volume for opening.

Troubleshooting Guide - Pressure Regulation Issues

Valve Will Not Pressure Regulate

Checks for correct line connections, open isolation valves, and stuck spool valve in pressure control.

Unstable Regulated Pressure

Addresses unstable pressure and water discharge by checking for trapped air in the system.

Schematic with External Filter

External Filter Kit Configuration

Diagram illustrating the valve setup with an external filter, manual selector, and connections.

Nelson 800 Series Specifications