Product Overview

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Siemens Modulating control valves with magnetic actuator, PN16 CA1N4454en
Building Technologies 24.04.2012
The magnetic actuator can be driven by a Siemens controller or a controller of other
manufacture that deliver a DC 0/2...10 V or DC 4... 20 mA output signal.
To achieve optimum control performance, it is recommended to use a 4-wire connec-
tion.
If the positioning signal is interrupted, or in the event of a power failure, the valve’s
return spring will automatically close control path 1  3.
Control path ports 1 –> 3 can be opened mechanically to between 0 and approximately
90 %, by turning the hand wheel clockwise.
The manual adjustment facility can also be used as a mechanical method of low limit
control, i.e. the valve will exercise its normal control function between the manually-set
position and the 100 % open position. For full-stroke automatic control, the hand wheel
must be set to 0 (the counterclockwise end stop).
Sizing
Δp
V
100
= differential pressure across the fully open valve and the valve’s control path 1  3 by a
volume flow
V
010
V
100
= volume flow through the fully open valve (H
100
)
Δpmax = max. permissible differential pressure across the valve’s control path (ports 1-3, 2-3) for the
entire actuating range of the motorized valve
100 kPa = 1 bar ≈ 10 mWC
1 m
3
/h = 0.278 l/s water at 20 °C
For water with > 20 % antifreeze use following generic formula to calculate volumetric
flow
V

100
:
V

100
= Volumetric flow [m
3
/h]
Q
100
= Design energy demand [kW]
∆T = Temperature difference between flow and return [K]
c = specific heat capacity [kJ/kgK]
[]
hm
Tc
Q
V /
3
100
100
3600
ρ ⋅Δ⋅
⋅
=

ρ = specific density [kg/m
3
]
Control
Spring return function
Manual control
Flow chart
Water
Water with Antifreeze
Generic formula