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BOSCH REXROTH
VT-MRPA1-1-1X/V0/0
R901094750
Valve Amplifiers

Pressure valve ampl, modul 1X

$1,106.00

BOSCH REXROTH

MATERIAL:  R901094750

SUMMARY:  Pressure valve ampl, modul 1X

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General information

The amplifier modules are snapped onto top hat rails according to EN 60715. The electrical connection is established via screw terminals. The modules are operated with 24 V direct voltage.

Power supply unit [1]

The amplifier modules have a power supply unit with making current limiter. This unit supplies all internally required positive and negative supply voltages.

Command value presetting

The internal command value signal is calculated from the total [3] of the external command value signal available at the differential input [2] and the zero point offset (zero point potentiometer "Zw"). A positive command value results in a current increase in the solenoid.

Enable function [11]

The enable function enables the current output stages and forwards the internal command value signal to the ramp generator. The enable signal is indicated by an LED on the front plate. If enable is connected, the internal command value is changed (with any kind of command value presetting) by the set ramp time. Thus, a controlled valve does not open abruptly.

Ramp generator [4]

The ramp generator limits the incline of the control output. The downstream step functions and amplitude attenuators do not extend or shorten the ramp time.

Information on ramp time setting and measurement:

Value at measuring socket
"t <” or "t >"

U/V

5

3

2

1

0.5

0.3

0.2

0.1

0.05

0.03

0.02

Current ramp time (±20 %)

t/ms

20

33

50

100

200

333

500

1000

2000

3333

5000

Formula for calculation of the ramp times:

 

t in ms, U in volt at the measuring socket

Characteristic curve generator [5]

Using the adjustable characteristic curve generator, step level and maximum values can be adjusted to the hydraulic requirements. The actual development of the characteristic curve through the zero point is not stepped but linear.

Amplitude limiter [6]

The internal command value is limited to approx. +110 % of the nominal range.

Oscillator [9]

The oscillator creates the control signal for the inductive position transducer.

Demodulator [10]

The demodulator supplies the actual value signal of the control spool position from the position transducer signal.

+100 % ≙ +10 V

Controller for the control spool position [7]

The position controller is optimized in a valve-specific manner.

Current output stage [8]

The current output stage creates the clocked solenoid current for the proportional valve. The solenoid current is limited to 2.4 A to 2.6 A. The output stage output is short-circuit-proof. The output stage is de-energized in case of an internal fault signal or if the enable signal is missing.

Fault recognition [14]

The position transducer cable is monitored for cable break and short-circuits on the primary side as well as for over-currents at the output stage.

 

[ ] = Assignment to the block diagram

01

Valve amplifier for proportional directional valves with electrical position feedback, analog, euro-card format

VT-MRPA

02

For valves: 4WRE (with one solenoid)

1

03

For valves: 4WRE 6...2X

1

For valves: 4WRE 10...2X

2

04

Component series 10 ... 19 (10 ... 19: unchanged installation and connection dimensions)

1X

05

Version: standard

V0

06

Further details in the plain text

*

01

02

03

04

05

06

VT-MRPA

1

1X

/

V0

/

*

General

Component series

1X

Type of electronics

Analog

Design

Modul

Voltage supply

Operating voltage

nominal

U

V

24

Lower limit value

UB(t)min

V

18

Upper limit value

UB(t)max

V

35

Power consumption

max.

PS max

VA

24

Current consumption

max.

I

A

2

Fuse

Thermal overload protection (with restart if the value falls below the temperature threshold)

Analog inputs

Command value

Voltage (differential input)

U

%

​0 ... ​10

Voltage (differential input)

Input resistance

R

≥ 50

Digital inputs

Enable

On (active) 1)

U

V

8.5 ... UB

Off (inactive)

U

V

0 ... 6.5
1) RE > 100 kΩ

Solenoid outputs

Solenoid current

max.

Imax

A

A

2.5

Clock frequency (freely clocking)

f

Hz

5 kHz

Solenoid output

other properties

Short-circuit-proof, clocked

Position transducer

Oscillator voltage

U

V

10 (I = 10 mA)

Oscillator frequency

U

V

5.6

Adjustment options

Zero point calibration

%

± 30

Amplitude attenuator 1)

for command value

%

0 ... 110

Zero point

actual valve position value

%

±10

Ramp time up/down

s

0.02 … 5

Step-change height

%

0 ... 50
1) Applies to a step level setting of 0%

Measuring sockets

Command value

"w"

V

0 ... 10

after ramp

"wR"

V

0 ... 10

Ramp time

“down"

s

0.02 ... 5

“up"

s

0.02 ... 5

Actual value

"x"

V

0 ... 10

Displays

LED display

green

Ready for operation

yellow

Enable

Supplementary information

Anschlussart

12 screw terminals

Mounting type

Top hat rail TH 35-7.5 according to EN 60715

Type of protection according to EN 60529

IP 20

Ambient temperature range

ϑ

°C

​0 … ​50

Storage temperature range

ϑ

°C

-25 … ​70

Weight

m

kg

0.14

For applications outside these parameters, please consult us!

Notice:

For information on environment simulation testing for the fields EMC (electro-magnetic compatibility), climate and mechanical load, see data sheet 30219-U

technical illustration-VT-MRPA1-1-1X/V0/0-Pressure valve ampl, modul 1X

LED displays

Ready for operation (green)

Enable (yellow)

Gw

Amplitude attenuator

Sw

Step-change height

Zw

Zero point command value

Zx

Zero point actual value

t <

 

Ramp time "Ramp up"

t >

 

Ramp time "Ramp down"

Measuring sockets

t <

 

Ramp time "Ramp up"

t >

 

Ramp time "Ramp down"

x

Actual value

w

Command value

wR

Command value after ramp

Reference potential

technical illustration-VT-MRPA1-1-1X/V0/0-Pressure valve ampl, modul 1X

Zw

Zero point command value

Zx

Zero point actual value

t <

 

Ramp time "Ramp up"

t >

 

Ramp time "Ramp down"

Sw

Step-change height

Gw

Amplitude attenuator

Gx

Sensitivity actual value

w

Command value

x

Actual value

wR

Command value after ramp

Ready for operation (green)

Enable

1

Power supply unit

2

Differential amplifier

3

Command value summation

4

Ramp generator

5

Characteristic curve generator

6

Amplitude limiter

7

Valve position controller

8

Power output stage

9

Oscillator

10

Demodulator

11

Enable

12

Proportional valve

13

Position transducer

14

Fault recognition

Mounting cavity R/T-31A; 4 main ports; thread M20 x 1.5 mm

Dimensions in mm

technical illustration-VT-MRPA1-1-1X/V0/0-Pressure valve ampl, modul 1X

Dimensions in mm

technical illustration-VT-MRPA1-1-1X/V0/0-Pressure valve ampl, modul 1X

The amplifier module may only be wired when de-energized.

Do not lay lines close to power cables.

Do not use free-wheeling diodes in the solenoid conductors.

The distance to aerial lines, radios, and radar systems has to be at least 1 m.

Always shield command value and position transducer lines; connect shielding to protective earthing (PE) on the module side.

In some cases (e.g. if PE is subject to strong interference) it can be necessary to connect the shield of the position transducer line directly to the L0 of the amplifier module; other side open (risk of ground loops).

Recommendation:
Also shield the solenoid conductors. For solenoid conductors up to a length of 50 m, use cable type LiYCY 1.5 mm2. For greater lengths, please contact us.

For switching command values, relays with gold-plated contacts have to be used (low voltages, low currents)!

Only carry out measurements at the module using instruments with Ri > 100 kΩ.

For setting the potentiometers, use a screwdriver with a blade width of 4 mm.

With a strongly fluctuating operating voltage, it may in individual cases be necessary to use an external smoothing capacitor with a capacity of at least 2200 µF.

Recommendation: Capacitor module VT 11110 (see data sheet 30750); sufficient for up to 3 amplifier modules

Setting information

Requirements: The system-specific circuitry must have been completed.

Zero point command value

Set the external command value presetting to zero

Set the internal command value to zero using the "Zw” zero point potentiometer and carry out a check at the "wR" measuring socket

Zero point actual value

Enable signal "OFF" or pull solenoid plug (valve moves to end position)

with potentiometer "Zx", set the actual value at measuring socket "x" to zero.

Recommendation:

At valves with V spool, set the zero point in operation with the hydraulic drive, i.e.

apply enable signal, check at measuring sockets "wR" and "w"

use the "Zx" potentiometer to bring the drive to a standstill

Ramp times

Set ramp time according to formula or table (see functional description "Ramp generator”) and check it at the "t >" and "t <" measuring sockets

Step level

Apply enable signal

Using the "Zw" zero point potentiometer, set the measurement signal at "wR" to –0,3 V

Using the "Sw" potentiometer, set the required step level

Check the required step level, set the zero point

Notice:

With external command value presetting, it must at least result in –0.3 V at the "wR" measuring socket.

Maximum values

Notice:

Before adjusting the maximum values, zero point and step levels must be set correctly.

The maximum current must not exceed the rated solenoid current!

Externally generate a command value of +100 %

Using the "Gw" potentiometer, set the required maximum control output and carry out a check at the "wR" and "w" measuring sockets