Operating Data; Optional Features - CALEFFI 578 Serie Documentation Technique

Operating data

1.1 PRESURE REDUCING FEATURE
Pressure reducing control (5) is a "normally open" control that senses main valve (1) outlet pressure changes. An incre-
ase in outlet pressure tends to close control (5) and a decrease in outlet pressure tends to open control (5). This causes
main valve cover pressure to vary and the main valve (1) to modulate (open and close) maintaining a relatively constant
outlet pressure.
Pressure reducing control (5) adjustment: Turn the adjusting screw clockwise to increase the setting.
1.2 OPENING SPEED CONTROL
Flow control (4) regulates the opening speed of main valve (1).
Flow control (4) adjustment: Turn the adjusting screw clockwise to make the main valve open more slowly.
1.3 (E*) EUROPEAN STANDARDS
ITEM (2) - Isolation ball valve:
The isolation ball valves are used to isolate the pilot system from main line pressure. These isolation ball valves must be
open during normal operation.
ITEM (3) - Y-Strainer with incorporated orifice:
The strainer is installed in the pilot supply line to protect the pilot system from foreign particles. The strainer screen must
be cleaned periodically.
1.4

OPTIONAL FEATURES

Suffix (A) - Internal strainer self-cleaning:
In some applications the self-cleaning strainer CLA-VAL, type X46A screwed at the inlet of main valve (1) reduces mainte-
nance generated by the cleaning of the standard strainer screen (3).
With this option (A) the strainer X46A replaces the strainer (3) and the orifice of the X44A strainer (3) is replaced by the
orifice assembly X58-CSA.
The cleaning of the strainer X46A is requesting its removal from the main valve body (1).
Suffix (C) - Closing speed:
Flow control (C) regulates the closing speed of main valve (1).
Flow control (C) adjustment: Turn the adjusting screw clockwise to make the valve close more slowly.
Suffix (Y) - High capacity filter:
When too many foreign particles are contained into the control pressure, it is recommended to replace the standard filter
X44 by the high capacity filter X43/80-EP, whose screen (Ø 80 mm x 110 mm) offers a much bigger filtration surface. Ho-
wever an additional union fitting, with incorporated calibrated orifice, model X52-VR must be mounted between the filter
outlet and the T-piece connecting the main valve control chamber.
1.5 CHECK LIST FOR PROPER OPERATION
• System valves open upstream and downstream.
• Air removed from the main valve cover and pilot system at all high points.
• Isolati on valves (2A), (2B) and (2C) open.
• Periodical cleaning of the filter screen (3) or of the self-cleaning strainer, [optional feature (A)].
Pressure Reducing Valve
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Serie 578