Proportional Directional Control
Valves

PRM7-04

Size D 04 (02) • 320 bar (4600 PSI) • 20 L/min (5.3 GPM )

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Compact design

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Operated by proportional solenoids

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Replaces
HA 5120 5/2009

Digital control

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HA 5120
6/2012

High sensitivity and slight hysteresis

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Installation dimensions to DIN 24 340 /
ISO 4401 / CETOP RP121-H

Functional Description
The proportional directional valve PRM7 consists of
a cast iron housing, a special control spool, two
centering springs with supporting washers, one or two
proportional solenoids, a position sensor or, if need be,
of a control box with digital electronics.
The measuring system of the position sensor consists of
a differential transformer with core and from
the evaluating electronic unit realized in hybrid
technique.
With the model without integrated electronic unit, the
electric connection of the solenoids is realized by the
connector plug to EN 175301-803, with the position
sensor output being connected by the G4W1F
connector plug. Both connectors are supplied.
The proportional valve with the integrated electronic unit
comprises an electronic control box that is mounted,
together with the position sensor, on either of the
solenoids. The connection of the position sensor with
the control box is provided by a cable. With the model
with two solenoids, the solenoid mounted opposite the
control box is connected with the control box by means
of a EN 175301-803, connector. The connection of the
supply voltage, control signal, program input and
external output of the position sensor is realized
by a 5-pin connector (ELKA 5012). The connection of
the external feedback is provided by a 5-pin connector,
which also has three supply voltages +24 V, +10V and
-5V for an external sensor available. The solenoid coils,
including the control box, can be turned in a range of
o
± 90 .The digital control unit enables the proportional
valve to be controlled on the basis of data required from
two feedback circuits.
In this case the proportional valve can be used as
follows:

1. Proportional directional valve
2. Only with the internal feedback from the spool
position sensor.
3. Only with the external feedback (pressure sensor,
position sensor, etc.).
4. With internal and external feedback.
The outlet current to the electromagnet coils is
controlled with the help of PWM. The electronic system
is equipped with an internal current feedback. The outlet
current in case of need may be modulated with the use
of a signal of dynamic lubrication. Single function
parameters are set up with the use of appropriate
software with the help of a computer connected to
the proportional switchboard through a serial interface
RS 232.
It is necessary to order a cable in accordance with
appropriate ordering number as mentioned on page 4.
The
digital
control
unit
utilizes
the
pulse-with-modulation (PWM) and supplies the
solenoids with current proportional to the control signal.
The supply current is additionally modulated with
a dither frequency. The individual functional parameters
are adjusted through software by means of a special
programmer, or by means of a computer through the
RS 232 interface. The correct function of the digital
control unit is signaled by a green LED. The incorrect
function (failure) is indicated by a red LED.
As a standard, the proportional valve is delivered with
factory setting. The model including also an external
feedback shall be consulted with the manufacturer.
With the basic surface treatment, the valve housing is
phosphate coated, whereas the surfaces of the
solenoids are zinc coated.

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