Modulating control valves with magnetic actuators, PN 16

for chilled and low-temperature hot water systems or for systems with media containing mineral oils (MX..461..P)

• Fast positioning time (<2 s), high-resolution stroke (1 : 1000), high rangeability
• Equal-percentage or linear valve characteristic (user-selected)
• Operating voltage AC / DC 24 V
• Switch-selected control signal DC 0/2…10 V or DC 4…20 mA
• DC 0…20 V phase cut control signal with SEZ91.6 external interface
• Indication of operating state, position feedback and manual control
• Wear-free inductive stroke measurement
• Fail-safe feature: A↑ AB closed when de-energized
• Low friction, robust, no maintenance required

The control valves are mixing or throughport valves with the ready fitted magnetic actuator for position control and position feedback. The short positioning time, high resolution and high rangeability make these valves ideal for modulating

• control of chilled and low-temperature hot water systems
• control or dosing control of fluids containing mineral oil (SAE05…SAE50), mineral-oilbased diesel fuels, heat transfer oils in closed circuits.
• Temperature control in mixing circuits for motor oil circulation
• Temperature control in mixing circuits for screw-compressors (compressed air)
• Temperature control of fuel circuits in mixing circuits for petrol and diesel oil
• High pressure control for the calibration of components for electronic injection components
• Control of cutting-oil emulsion for industrial grinding machines

Technical and mechanical design

For a detailed description of operation, refer to data sheet CA1N4028E.

Control operation

The electronics module converts the positioning signal to a phase-cut power signal which generates a magnetic field in the coil. This causes the armature to change its position in accordance with the interacting forces (magnetic field, counterspring, hydraulics). The armature responds rapidly to any change in signal, transferring the corresponding movement directly to the valve plug, enabling fast changes in load to be corrected quickly and accurately. The valve’s position is measured continuously (inductive). The internal positioning controller balances any disturbance in the system rapidly and delivers the position feedback signal. The valve stroke is proportional to the positioning signal.

Spring return facility

If the positioning signal is interrupted, or in the event of a power failure, the valve’s
return spring will automatically close control path A ↑ AB.

Control

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 connection.

Manual control

MANUAL
The valve control path (ports A ↑ AB) can be opened manually to between 80 and 90 % of the full stroke (depending on DN) by pressing the hand wheel inwards and turning it clockwise (MANUAL setting). This disables the control signal from the controller, the green LED is flashing.
OFF
To disable automatic control of the valve, press the hand wheel inwards and turn it anti-clockwise (to the OFF position). The valve will close, the green LED is flashing.
AUTO
For automatic control, the hand wheel must be set to the AUTO position (the hand wheel will spring out), the green LED is lit.