Data Sheet for Product

M3PFY..Series Modulating Control Valve Technical Instructions
ANSI 125 (PN 16) with Magnetic Actuator Document No. CA1N4454E-P25
January 17, 2003
Siemens Building Technologies, Inc. Page 3
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Technical/
Mechanical Design,
Continued
If the power is switched off or fails, the valve control path (Port 1 → 3) is automatically
closed by the force of the spring.
The valve stem is sealed with a maintenance-free O-ring gland.
Manual Adjustment
Control path Ports 1
3 can be opened mechanically to between 0 and approximately
90%, by turning the handwheel clockwise. The manual adjustment facility can also be
used as a mechanical method of low limit control, that is, the valve will exercise its
normal control function between the manually-set position and the 100% open position.
For full-stroke automatic control, the handwheel must be set to 0 (the counterclockwise
end-stop).
Accessories
Close off Port 2 in straight-through applications. The blank flange kit consists of a seal,
screws, spring washers and nuts.
Z155/80 and Z155/100 Blank flange kit for flanged valves with 3-inch to 4-inch line
size.
Sizing
Water Flow Equation:
p
Q
C
v
∆
=
Where:
C
v
= Flow Coefficient
Q = Volumetric flow rate (gpm)
∆p = Pressure drop, psi
Installation
Mounting instructions for the valve and terminal housing are enclosed with the valve.
CAUTION:
Always disconnect the power before fitting or removing the terminal
housing. The terminal housing is calibrated and matched to the actuator,
and should be replaced only by qualified personnel.
• The M3P...Y valve is suitable for straight-through or three-way applications but can
only be installed in a mixing arrangement.
• Vertical to horizontal mounting – do not mount below horizontal.
• The actuator must not be insulated.
• Only three-way valves are supplied, but these may be used in straight-through
applications by sealing Port 2 as described in the Straight-through Application
section.
NOTE: It is recommended that water systems be cleaned, flushed and treated in
accordance with Current Good Practices.