Bosch Rexroth VT-MRMA1-1 User manual

Operating instructions
RE 30214-B/03.2019
Replaces: 03.2017
English
VT-MRMA1-1
Analog amplifier module

The data specified only serve to describe the
product. No statements concerning a certain
condition or suitability for a certain application
can be derived from our information. The
information given does not release the user
from the obligation of own assessments and
verification. It must be remembered that our
products are subject to a natural process of
wear and aging.
© This document, as well as the data,
specifications and other information set forth in
it, are the exclusive property of Bosch Rexroth.
It may not be reproduced or given to third
parties without its consent.
An example configuration is shown on the title
page. The delivered product may, therefore,
differ from the product which is pictured.
The original operating instructions were
created in the German language.

RE 30214-B/03.2019, VT-MRMA1-1, Bosch Rexroth AG
3/52Content
Content
1 About this documentation 5
1.1 Validity of the documentation 5
1.2 Required and supplementary documentation 5
1.3 Representation of information 5
1.3.1 Safety instructions 5
1.3.2 Symbols 6
1.3.3 Terms used 6
1.3.4 Abbreviations used 6
2 Safety instructions 7
2.1 About this chapter 7
2.2 Intended use 7
2.3 Improper use 7
2.4 Personnel qualifications 7
2.5 General safety instructions 8
2.6 Product-specific safety instructions 8
3 General notes on damage to material and the product 10
4 Scope of delivery 11
5 About this product 12
5.1 Performance description 12
5.1.1 Block circuit diagram of the controller structure of the analog amplifier
module: 13
5.2 Product description 13
5.2.1 Components that can be connected 13
5.2.2 Function 14
5.2.3 Functions within the amplifier module 15
5.2.4 Controller and functions closely related to the controller 16
5.2.5 Actual value preparation 17
5.2.6 Monitoring functions 19
5.2.7 Measuring point changeover switch (15) 22
5.3 Identification of the product 22
6 Transport and storage 23
6.1 Storing the VT-MRMA1 23
7 Installation 24
7.1 Installation conditions 25
7.2 Required tools 25
7.3 Recommended accessories 26
7.4 Installing the VT-MRMA1 26
7.5 System-specific circuitry of the amplifier module 27
7.6 Overview of connections 27
7.6.1 Terminal assignment 28
7.6.2 Connection of the power supply unit 29
7.6.3 Connection of the pressure reducing valve 29
7.6.4 Connection of actual pressure value cables (pressure transducer) 30
7.6.5 Connection of the control 31
7.6.6 Plug-in screw connectors 31
8 Commissioning 33

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8.1 Adjustment, measuring and indicator elements 33
8.1.1 DIL switches 33
8.1.2 Potentiometers 37
8.1.3 Measuring signal and measuring point selector switch 38
8.1.4 LEDs 38
8.2 Commissioning instructions 39
8.3 Fine tuning of the complete system 40
8.4 Application example 41
9 Operation 43
10 Maintenance and repair 43
10.1 Cleaning and care 43
10.2 Maintenance 43
10.3 Repair 43
11 Demounting and replacement 44
11.1 Preparing demounting 44
11.2 Demounting 44
11.3 Preparing the components for storage or further use 44
12 Disposal 44
12.1 Environmental protection 44
13 Extension and conversion 44
14 Troubleshooting 45
14.1 How to proceed for troubleshooting 45
14.2 Erroneous states und error diagnostics 45
15 Technical data 46
16 Annex 47
16.1 Addresses 47
17 Alphabetical index 48

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1 About this documentation
1.1 Validity of the documentation
This documentation is valid for the following analog amplifier module:
• VT-MRMA1-1-1X/V0/0
This documentation is intended for fitters, operators, service technicians and plant
operators.
This documentation contains important information on the safe and appropriate
installation, transport, commissioning, maintenance, operation, removal and simple
troubleshooting of the product.
▶ Read this documentation thoroughly, especially chapter 2 “Safety instructions“
and chapter 3 “General notes on damage to material and the product“, before
working with the analog amplifier module.
1.2 Required and supplementary documentation
▶ Only commission the product, when you have the documents marked with the
book symbol at hand and have understood and observed them.
Table 1: Required and supplementary documentation
1.3 Representation of information
In order that this documentation allows you to work directly and safely with your
product, standardized safety notes, symbols, terms and abbreviations are used. For a
better understanding, these are explained in the following sections.
1.3.1 Safety instructions
This documentation contains safety notes in Chapter 2.6 “Product-specific safety
instructions“ and Chapter 3 “General notes on damage to material and the product“
as well as before a sequence of activities or instructions for action, which involve the
risk of personal injury or damage to equipment. The measures described for averting
the hazard have to be observed.
Safety notes are structured as follows:
SIGNAL WORD
Type and source of hazard!
Consequences in the case of non-observance
▶ Measures to avert the hazard
▶ <Enumeration>
Title Document number Type of
document
Analog amplifier module VT-MRMA1-1 30214 Data sheet
Pressure transducer for hydraulic applications, type HM20-2X 30272 Data sheet
Proportional pressure reducing valve with DC motor actuation 29173 Data sheet
Power supply unit type VT-NE30-2X 29929 Data sheet

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•Warning symbol: draws attention to a hazard
•Signal word: identifies the degree of hazard
•Type and source of hazard: identifies the type or source of the hazard
•Consequences: describes the consequences in the case of non-observance
•Precautions states, how the hazard can be avoided
Table 2: Hazard classes according to ANSI Z535.6-2011
Warning sign, signal word Meaning
DANGER Indicates a hazardous situation which, if not avoided, will
certainly result in death or serious injury.
WARNING Indicates a hazardous situation which, if not avoided, could
result in death or serious injury.
CAUTION Indicates a hazardous situation which, if not avoided, could
result in minor or moderate injury.
NOTICE Damage to property: The product or the environment can be
damaged.
1.3.2 Symbols
The following symbols refer to notes, which are not relevant to safety, but increase
the legibility of the documentation.
Table 3: Meaning of symbols
Symbol Meaning
If this information is disregarded, the product cannot be used or operated
in an optimum manner.
▶ Individual, independent action
1.
2.
3.
Numbered instructions for action:
The numbers indicate that the activities are to be carried out consecutively.
1.3.3 Terms used
The following terms are used in this documentation:
Table 4: Terms used
Term Meaning
VT-MRMA1 Analog amplifier module
UB Operating voltage
HM20 Pressure transducer
1.3.4 Abbreviations used
The following abbreviations are used in this documentation:
Table 5: Abbreviations used
Abbreviation Meaning
EMC ElectroMagnetic Compatibility
PE Protective Earth
PELV Protective Extra Low Voltage

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2 Safety instructions
2.1 About this chapter
The analog amplifier module has been manufactured according to good engineering
practice. There is, however, still a risk of personal injury or damage to equipment
if you do not observe this chapter and the safety instructions contained in this
documentation.
▶ Read these instructions completely and thoroughly before working with the
product.
▶ Keep this documentation in a location where it is accessible to all users at all
times.
▶ Always pass the product together with the required documentation to third
parties.
2.2 Intended use
The analog amplifier module is an electrical component.
You may use the product as follows:
• For controlling a DC motor-actuated proportional pressure reducing valve with
electrical position feedback, type (Z)DRS, size 6, component series 1X
The product is intended exclusively for professional use and not for private usage.
Operation according to the intended use also implies that you have read
and understood this documentation completely, especially chapter 2 “Safety
instructions“.
2.3 Improper use
Any use other than described in the section “Intended use” is considered as
improper and is therefore not permitted.
For damage resulting from improper use, Bosch Rexroth AG will not bear liability.
The risks arising from improper use lie exclusively with the user.
Improper use includes, but is not limited to the following, foreseeable misuse:
• operating the analog amplifier module outside the specified performance limits and
operating conditions, especially the prescribed ambient conditions;
2.4 Personnel qualifications
The activities described in this documentation require basic knowledge of electrics
and hydraulics as well as knowledge of the associated technical terms. To ensure
safe usage, these activities may therefore only be carried out by qualified personnel
or under the direction and supervision of qualified personnel.
Qualified personnel are those who can recognize possible hazards and institute
the appropriate safety measures due to their professional training, knowledge and
experience, as well as their understanding of the relevant conditions pertaining to
the work to be done. Qualified personnel have to observe relevant specialist rules
and have the required expertise.
With regard to hydraulic products, specialist knowledge means, for example:
• The ability to read and entirely understand hydraulic circuit diagrams,

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Bosch Rexroth AG, VT-MRMA1-1, RE 30214-B/03.2019
• the complete understanding in particular of interrelationships with regard to safety
equipment and
• knowledge of the function and structure of hydraulic components.
Bosch Rexroth offers qualifying training courses in specific fields. You can find an
overview of training contents on the Internet at:
http://www.boschrexroth.com
2.5 General safety instructions
• Observe valid regulations for accident prevention and environmental protection.
• Observe the safety regulations and rules of the country where the product is used/
operated.
• Use Rexroth products only in technically perfect condition.
• Observe all notes given on the product.
• Persons who install, commission, operate, demount or maintain Rexroth products
must not consume any alcohol, drugs or pharmaceuticals that may affect their
ability to respond.
• Only use accessory and spare parts approved by the manufacturer in order to rule
out personnel hazards arising from unsuitable spare parts.
• Adhere to the technical data and ambient conditions specified in the product
documentation.
• If unsuitable products are installed or used in safety-relevant applications,
unintended operational states may occur in the application that can cause personal
injury and/or damage to property. Therefore, use the product only in safety-relevant
applications such as in explosion protection areas or in safety-related parts of a
control (functional safety), if this use is expressly specified and permitted in the
documentation.
• You may commission the product only when it has been established that the final
product (for example, a machine or system), in which the Rexroth products is
installed, complies with national regulations, safety regulations and standards
relevant for the application.
• Observe safety-relevant information and information on risks in the operating
instructions of the manufacturer of the connected hydraulic system before
commissioning the analog amplifier module with a hydraulic system.
• Technical data, the connection and installation conditions can be found in the
product documentation and have to be strictly observed.
• Observe general installation and safety regulations for working on electrical
systems.
• Generally, you may not modify or convert the product.
2.6 Product-specific safety instructions
If for certain work to be carried out safety features on the product are temporarily
not used for functional reasons, you have to ensure the same safety and protection
level in a different way in accordance with valid regulations.

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WARNING
Hazardous movements!
Risk of injury due to incorrect activation of the proportional pressure reducing valve
via the analog amplifier module and resulting unforeseeable machine movements.
▶ Operate the amplifier only together with the valves specified in the type code.
▶ Observe safety in accordance with EN 13849 or IEC 62061.
▶ If persons have to enter the hazard zone while the control is active, provide
superordinate monitoring functions or measurers for personal safety. The plant
manufacturer/user has to rate and dimension these measures on the basis of
a risk and failure analysis according to the specific situation on site. The safety
regulations valid for the system have to be taken into account for this.
▶ The electronics emits interference to other electronics within the permitted limit
values. This can cause malfunction in the control process. Only use electronics
below the EMC limit values or provide appropriate shielding.
▶ The electronics of the analog amplifier module VT-MRMA1 responds to
electromagnetic interference from non-shielded, improperly installed or wrongly
connected signal cables. If the limit values given in the data sheet are exceeded,
malfunction or uncontrolled movements are possible. Adhere to the limit values
given in the data sheet, use only electronics below the EMC limit values or
provide proper shielding.
▶ Electrostatic processes, an inadequate grounding concept or missing
equipotential bonding can lead to damage to the electronics and hence
cause malfunction or uncontrolled movements of the machine. Ensure proper
grounding and provide equipotential bonding.
▶ Using the product outside the specified IP protection class can result in
short-circuit and malfunction and hence in uncontrolled machine movements.
Therefore, use the product only within the IP protection class and in
environments as specified in the data sheet.
▶ Provide safety functions for personal safety separately. The analog amplifier
module VT-MRMA1 itself does not include safety functions for personal safety
and is no safety-related component.
High electric voltage through incorrect connection!
Danger to life, risk of injury due to electric shock.
▶ When carrying out any work, disconnect the relevant machine section from the
power supply and protect it against being switched on again.
▶ Only connect devices, electrical components and lines which feature protective
extra low voltage (PELV) to connections or terminals having voltages from 0 to
50 Volt.
▶ Only connect voltages and power circuits that feature safe isolation from
dangerous voltages. Safe electrical isolation can be achieved with, for example,
isolating transformers, safe opto-couplers or mains-free battery operation.

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Bosch Rexroth AG, VT-MRMA1-1, RE 30214-B/03.2019
WARNING
Lightning!
Risk of uncontrolled machine movements.
▶ An inadequate grounding concept or missing equipotential bonding can lead to
damage to the electronics. Provide for equipotential bonding of the device.
Failures and defects in the control current circuits or the energy supply!
Risk of uncontrolled machine movements.
▶ Observe safety in accordance with EN 13849 or IEC 62061.
CAUTION
Hot surfaces!
Risk of burning.
▶ System parts can heat up during operation. Let system parts cool down before
touching it or wear protective gloves.
3 General notes on damage to material and
the product
The warranty is valid exclusively for the configuration delivered.
• Warranty claims will be rejected in the case of improper installation,
commissioning and operation as well as in the case of use not in accordance with
the intended purpose and/or improper handling.
NOTICE
High voltage!
Risk of damage to the analog amplifier module.
▶ Wire the analog amplifier module only when disconnected from the power
supply.
Overloading!
Risk of overloading and damage to the supply cable in the case of insufficient
dimensioning and/or operation with several electrical devices.
▶ Provide current limitation by overload protection.
▶ Select an appropriate rating of power supply unit and cables.
Short-circuit!
Risk of overloading and damage of the supply cable in the case of defects of the
electrical device.
▶ Provide current limitation by overload protection.
Impermissible temperature range!
Risk of overheating. The device can be thermally destroyed.
▶ Adhere to the specification in the data sheet.