Technology Of Proportional Valves; Figure 1: Information Flow In The Proportional Hydraulics - WAGO 750-632 Manual

WAGO I/O System 750/753
750-632 Proportional Valve Module
3

Technology of Proportional Valves

Proportional valves can be used to control the throughput of liquids or gases. The
throughput is determined by a lifting armature that is pressed on the valve seat
by a spring. The valve is thus closed in the inactive state. A further component of
the proportional valve is an electromagnet that consists of one or more coils. This
magnet functions in a direction opposite that of the lifting armature. The force
applied by the electromagnet is proportional to the current supplied. By regulating
the current flow, the position of the lifting armature and thus the throughput in the
proportional valve can be controlled.
Proportional valves are available in different versions. Essential differences
include, among others:
• the number of coils,
• the maximum possible throughput, and
• the electrical current that must be supplied.
Proportional valve modules can control proportional valves very precisely. They
are installed upstream of each proportional valve in use. During operation, they
generate the current which adjusts the respective proportional valve to the
desired throughput. In addition, they can offer expanded functions, such as a
setpoint value control by means of a ramp generator or dithering for static
compensation.
The following figure shows the information flow during interaction of the individual
technical components:

Figure 1: Information Flow in the Proportional Hydraulics

Technology of Proportional Valves
Version 1.3.1, valid from FW/HW-Version 01/01
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Manual