BONFIGLIOLI Vectron ACTIVE CUBE Instructions for use

ACTIVE CUBE
Application manual
Safe Torque Off

TABLE OF CONTENTS
1General information about the documentation ............................................................. 5
1.1 Instruction manuals.................................................................................... 5
1.2 This document ............................................................................................ 6
1.3 Warranty and liability ................................................................................. 6
1.4 Obligation ................................................................................................... 7
1.5 Copyright .................................................................................................... 7
1.6 Storage........................................................................................................ 7
2General safety instructions and information on use...................................................... 8
2.1 Terminology................................................................................................ 8
2.2 Designated use ........................................................................................... 9
2.3 Misuse......................................................................................................... 9
2.3.1 Explosion protection ........................................................................................... 9
2.4 Residual risks............................................................................................ 10
2.5 Safety and warning signs at frequency inverter....................................... 10
2.6 Warning information and symbols used in the user manual.................... 11
2.6.1 Hazard classes...................................................................................................11
2.6.2 Hazard symbols.................................................................................................11
2.6.3 Prohibition signs................................................................................................11
2.6.4 Personal safety equipment .................................................................................11
2.6.5 Recycling ..........................................................................................................12
2.6.6 Grounding symbol..............................................................................................12
2.6.7 ESD symbol.......................................................................................................12
2.6.8 Information signs ..............................................................................................12
2.7 Directives and guidelines to be adhered to by the operator .................... 13
2.8 Operator's general plant documentation.................................................. 13
2.9 Operator's/operating staff's responsibilities............................................ 13
2.9.1 Selection and qualification of staff ......................................................................13
2.9.2 General work safety...........................................................................................13
2.10 Organizational measures.......................................................................... 14
2.10.1 General.............................................................................................................14
2.10.2 Use in combination with third-party products.......................................................14
2.10.3 Transport and Storage.......................................................................................14
2.10.4 Handling and installation....................................................................................14
2.10.5 Electrical connections.........................................................................................14
2.10.5.1 The five safety rules ..........................................................................................15
2.10.6 Safe operation...................................................................................................15
2.10.7 Maintenance and service/troubleshooting............................................................16
2.10.8 Final decommissioning.......................................................................................16
3Safety Instructions on Function „Safe Torque Off“ (STO)........................................... 17
3.1 Approved Devices ..................................................................................... 18
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4Information of Risk Analysis and Risk Assessment..................................................... 19
5General Description of Safety Function ....................................................................... 20
5.1 Integrated Safety Function....................................................................... 20
5.2 Functional Safety...................................................................................... 20
5.3 Classification the safety requirement....................................................... 20
6Description of ACTIVE Cube Safety Function............................................................... 21
6.1 Two-Channel Monitoring .......................................................................... 22
6.2 Diagnosis function and enforced dynamizing........................................... 24
6.3 Diagnosis indicators.................................................................................. 25
7Requirements to be met by installation....................................................................... 26
7.1 Instructions on installation of safety equipment ..................................... 26
7.2 External Safety Control Equipment .......................................................... 27
7.3 External DC 24 V power supply ................................................................ 27
7.4 DC 24 V Power supply by ACU .................................................................. 28
8Requirements to be met in operation.......................................................................... 28
9Requirements to be met by acceptance inspection..................................................... 28
10 Application Examples................................................................................................... 29
10.1 Direct Stop, Stop Category 0 .................................................................... 30
10.2 Direct Stop with Feedback to PLC, Stop Category 0................................. 31
10.3 Direct Stop, Stop Category 1 .................................................................... 32
10.4 Direct Stop with Feedback to PLC, Stop Category 1................................. 33
10.5 Internal DC 24 V Supply, Stop Category 1................................................ 34
10.6 Group Stop, Stop Category 1 .................................................................... 35
10.7 Error exclusion “short circuit” in the cabinet ........................................... 36
11 Checklist....................................................................................................................... 37
12 Safety Function Test Report ........................................................................................ 38
13 STO status (diagnosis)................................................................................................. 38
14 Index of Change........................................................................................................... 39
15 Index............................................................................................................................ 40
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1General information about the documentation
The present documentation complements the operating instructions and the Quick Start Guide of the
frequency inverter ACTIVE Cube (ACU).
1.1 Instruction manuals
For better clarity, the documentation is structured according to the customer-specific requirements
made on the frequency inverter.
Quick start guide
The Quick Start Guide describes the basic steps required for mechanical and electrical installation of
the frequency inverter. The guided commissioning supports you in the selection of necessary parame-
ters and the configuration of the frequency inverter by the software.
Operating instructions
The Operating Instructions describe and document all functions of the frequency inverter. The param-
eters required for adapting the frequency inverter to specific applications as well as the wide range of
additional functions are described in detail.
Application manual
The application manual supplements the documentation for purposeful installation and commissioning
of the frequency inverter. Information on various subjects connected with the use of the frequency
inverter is described specific to the application.
If you need a copy of the documentation or additional information, contact your local representative
of BONFIGLIOLI.
The present documentation was prepared with great care and it was subjected to extensive and re-
peated reviews. For reasons of clarity, it was not possible to include all details of all types of the prod-
uct in the documentation. Neither was it possible to consider all conceivable installation, operation or
maintenance situations. If you require further information or if you meet with specific problems which
are not dealt with in sufficient detail in the documentation, contact your local BONFIGLIOLI agent.
We would also like to point out that the contents of this documentation do not form part of any pre-
vious or existing agreement, assurance or legal relationship. Neither are they intended to supplement
or replace such agreements, assurances or legal relationships. The manufacturer's obligations are
exclusively specified in the relevant purchase contract. This contract also contains all and any warran-
ty regulations which may apply to the relevant scope of supply. These contractual warranty provisions
are neither extended nor limited by the specifications contained in this documentation.
The manufacturer reserves the right to correct or amend the specifications, product information and
omissions in these operating instructions without notice. The manufacturer shall not be liable for any
damage, injuries or costs which may be caused by the aforementioned reasons.
This documentation was written in german language. Other language versions are translated.
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1.2 This document
The present documentation complements the operating instructions ACTIVE Cube (ACU). It contains
additional safety information and requirements for the operation or ACTIVE Cube (ACU) in safety-
oriented applications. Use in safety-oriented machines shall be permissible only after this documenta-
tion has been read carefully and understood.
The applicable basic standards as well as application-specific and specific national standards shall also
be complied with – the standards referred to in this manual shall also be complied with.
For this reason, make sure you read the user manual carefully.
WARNING
Compliance with the documentation is required to ensure safe operation of the frequen-
cy inverter. BONFIGLIOLI VECTRON GmbH shall not be held liable for any damage
caused by any non-compliance with the documentation.
In case any problems occur which are not covered by the documentation sufficiently,
please contact the manufacturer.
1.3 Warranty and liability
BONFIGLIOLI VECTRON GmbH would like to point out that the contents of this user manual do not
form part of any previous or existing agreement, assurance or legal relationship. Neither are they
intended to supplement or replace such agreements, assurances or legal relationships. Any obligations
of the manufacturer shall solely be based on the relevant purchase agreement which also includes the
complete and solely valid warranty stipulations. These contractual warranty provisions are neither
extended nor limited by the specifications contained in this documentation.
The manufacturer reserves the right to correct or amend the specifications, product information and
omissions in these operating instructions without notice. The manufacturer shall not be liable for any
damage, injuries or costs which may be caused by the aforementioned reasons.
In addition to that, BONFIGLIOLI VECTRON GmbH excludes any warranty/liability claims for any per-
sonal and/or material damage if such damage is due to one or more of the following causes:
•inappropriate use of the frequency inverter,
•non-compliance with the instructions, warnings and prohibitions contained in the documentation,
•unauthorized modifications of the solar inverter,
•insufficient monitoring of parts of the machine/plant which are subject to wear,
•repair work at the machine/plant not carried out properly or in time,
•catastrophes by external impact and Force Majeure.
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1.4 Obligation
This user manual must be read before commissioning and complied with. Anybody entrusted with
tasks in connection with the
•transport,
•assembly,
•installation of the frequency inverter and
•operation of the frequency inverter
must have read and understood the user manual and, in particular, the safety instructions in order to
prevent personal and material losses.
1.5 Copyright
In accordance with applicable law against unfair competition, this user manual is a certificate. Any
copyrights relating to it shall remain with
BONFIGLIOLI VECTRON GmbH
Europark Fichtenhain B6
47807 Krefeld
Germany
These user manual is intended for the operator of the frequency inverter. Any disclosure or copying of
this document, exploitation and communication of its contents (as hardcopy or electronically) shall be
forbidden, unless permitted expressly.
Any non-compliance will constitute an offense against the copyright law dated 09 September 1965,
the law against unfair competition and the Civil Code and may result in claims for damages. All rights
relating to patent, utility model or design registration reserved.
1.6 Storage
The documentation form an integral part of the frequency inverter. It must be stored such that it is
accessible to operating staff at all times. In case the frequency inverter is sold to other users, this user
manual must also be handed over.
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2General safety instructions and information on use
The chapter "General safety instructions and information on use" contains general safety instructions
for the Operator and the Operating Staff. At the beginning of certain main chapters, some safety in-
structions are included which apply to all work described in the relevant chapter. Special work-specific
safety instructions are provided before each safety-relevant work step.
2.1 Terminology
According to the documentation, different activities must be performed by certain persons with certain
qualifications.
The groups of persons with the required qualification are defined as follows:
Operator
This is the entrepreneur/company who/which operates the frequency inverter and uses it as per the
specifications or has it operated by qualified and instructed staff.
Operating staff
The term Operating Staff covers persons instructed by the Operator of the frequency inverter and
assigned the task of operating the frequency inverter.
Qualified staff
The term Qualified Staff covers staff who is assigned special tasks by the Operator of the frequency
inverter, e.g. installation, maintenance and service/repair and troubleshooting. Based on their qualifi-
cation and/or know-how, qualified staff must be capable of identifying defects and assessing func-
tions.
Qualified electrician
The term Qualified Electrician covers qualified and trained staff who has special technical know-how
and experience with electrical installations. In addition, Qualified Electricians must be familiar with the
applicable standards and regulations, they must be able to assess the assigned tasks properly and
identify and eliminate potential hazards.
Instructed person
The term Instructed Person covers staff who was instructed and trained about/in the assigned tasks
and the potential hazards that might result from inappropriate behavior. In addition, instructed per-
sons must have been instructed in the required protection provisions, protective measures, the appli-
cable directives, accident prevention regulations as well as the operating conditions and verified their
qualification.
Expert
The term Expert covers qualified and trained staff who has special technical know-how and experience
relating to frequency inverter. Experts must be familiar with the applicable government work safety
directives, accident prevention regulations, guidelines and generally accepted rules of technology in
order to assess the operationally safe condition of the frequency inverter.
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2.2 Designated use
The frequency inverter is designed according to the state of the art and recognized safety regulations.
The frequency inverters are electrical drive components intended for installation in industrial plants or
machines. Commissioning and start of operation is not allowed until it has been verified that the ma-
chine meets the requirements of the EC Machinery Directive 2006/42/EC and DIN EN 60204-1.
The frequency inverters meet the requirements of the low voltage directive 2006/95/EEC and DIN
EN 61800-5-1. CE-labeling is based on these standards. Responsibility for compliance with the EMC
Directive 2004/108/EC lies with the operator. Frequency inverters are only available at specialized
dealers and are exclusively intended for commercial use as per EN 61000-3-2.
No capacitive loads may be connected to the frequency inverter.
The technical data, connection specifications and information on ambient conditions are indicated on
the rating plate and in the documentation and must be complied with in any case.
2.3 Misuse
Any use other than that described in "Designated use" shall not be permissible and shall be consid-
ered as misuse.
For example, the machine/plant must not be operated
•by uninstructed staff,
•while it is not in perfect condition,
•without protection enclosure (e.g. covers),
•without safety equipment or with safety equipment deactivated.
The manufacturer shall not be held liable for any damage resulting from such misuse. The sole risk
shall be borne by the operator.
2.3.1 Explosion protection
The frequency inverter is an IP 20 protection class device. For this reason, use of the device in explo-
sive atmospheres is not permitted.
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2.4 Residual risks
Residual risks are special hazards involved in handling of the frequency inverter which cannot be elim-
inated despite the safety-compliant design of the device. Residual risks are not obviously identifiable
and can be a potential source of injury or health hazard.
Typical residual hazards include:
Electrical hazard
Danger of contact with energized components due to a defect, opened covers or enclosures or im-
proper working on electrical equipment.
Danger of contact with energized components inside of the frequency inverter if no external discon-
nection device was installed by the operator.
Electrostatic charging
Touching electronic components bears the risk of electrostatic discharges.
Thermal hazards
Risk of accidents by hot machine/plant surfaces, e.g. heat sink, transformer, fuse or sine filter.
Charged capacitors in DC link
The DC link may have dangerous voltage levels even up to three minutes after shutdown.
Danger of equipment falling down/over, e.g. during transport
Center of gravity is not the middle of the electric cabinet modules.
2.5 Safety and warning signs at frequency inverter
•Comply with all safety instructions and danger information provided on the frequency inverter.
•Safety information and warnings on the frequency inverter must not be removed.
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2.6 Warning information and symbols used in the user manual
2.6.1 Hazard classes
The following hazard identifications and symbols are used to mark particularly important information:
DANGER
Identification of immediate threat holding a high
risk of death or serious injury if not
avoided.
WARNING
Identification of immediate threat holding a medium
risk of death or serious injury if
not avoided.
CAUTION
Identification of immediate threat holding a low risk of minor or moderate physical inju-
ry if not avoided.
NOTE
Identification of a threat holding a risk of material damage if not avoided.
2.6.2 Hazard symbols
Symbol
Meaning
Symbol
Meaning
General hazard Suspended load
Electrical voltage Hot surfaces
2.6.3 Prohibition signs
Symbol
Meaning
No switching; it is forbidden to switch
the machine/plant, assembly on
2.6.4 Personal safety equipment
Symbol
Meaning
Wear body protection
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2.6.5 Recycling
Symbol
Meaning
Recycling, to avoid waste, collect all
materials for reuse
2.6.6 Grounding symbol
Symbol
Meaning
Ground connection
2.6.7 ESD symbol
Symbol
Meaning
ESD: Electrostatic Discharge (can
damage components and assemblies)
2.6.8 Information signs
Symbol
Meaning
Tips and information making using the
frequency inverter easier.
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2.7 Directives and guidelines to be adhered to by the operator
The operator must follow the following directives and regulations:
•Ensure that the applicable workplace-related accident prevention regulations as well as other ap-
plicable national regulation are accessible to the staff.
•An authorized person must ensure, before using the frequency inverter, that the device is used in
compliance with its designated use and that all safety requirements are met.
•Additionally, comply with the applicable laws, regulations and directives of the country in which
the frequency inverter is used.
−Any additional guidelines and directives that may be required additionally shall be defined by
the operator of the machine/plant considering the operating environment.
2.8 Operator's general plant documentation
•In addition to the user manual, the operator should issue separate internal operating instructions
for the frequency inverter. The user manual of the frequency inverter must be included in the user
manual of the whole plant.
2.9 Operator's/operating staff's responsibilities
2.9.1 Selection and qualification of staff
•Any work on the frequency inverter may only be carried out by qualified technical staff. The staff
must not be under the influence of any drugs. Note the minimum age required by law. Define the
staff's responsibility in connection with all work on the frequency inverter clearly.
•Work on the electrical components may only be performed by a qualified electrician according to
the applicable rules of electrical engineering.
•The operating staff must be trained for the relevant work to be performed.
2.9.2 General work safety
•In addition to the user manual of the machine/plant, any applicable legal or other regulations
relating to accident prevention and environmental protection must be complied with. The staff
must be instructed accordingly.
Such regulations and/or requirements may include, for example, handling of hazardous media and
materials or provision/use of personal protective equipment.
•In addition to this user manual, issue any additional directives that may be required to meet spe-
cific operating requirements, including supervision and reporting requirements, e.g. directives re-
lating to work organization, workflow and employed staff.
•Unless approved of expressly by the manufacturer, do not modify the frequency inverter in any
way, including addition of attachments or retrofits.
•Only use the frequency inverter if the rated connection and setup values specified by the manu-
facturer are met.
•Provide appropriate tools as may be required for performing all work on the frequency inverter
properly.
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2.10 Organizational measures
2.10.1 General
•Train your staff in the handling and use of the frequency inverter and the machine/plant as well
as the risks involved.
•Use of any individual parts or components of the frequency inverter in other parts of the opera-
tor's machine/plant is prohibited.
•Optional components for the frequency inverter must be used in accordance with their designated
use and in compliance with the relevant documentation.
2.10.2 Use in combination with third-party products
•Please note that BONFIGLIOLI VECTRON GmbH will not accept any responsibility for compatibility
with third-party products (e.g. motors, cables or filters).
•In order to enable optimum system compatibility, BONFIGLIOLI VECTRON GmbH office compo-
nents facilitating commissioning and providing optimum synchronization of the machine/plant
parts in operation.
•If you use the frequency inverter in combination with third-party products, you do this at your
own risk.
2.10.3 Transport and Storage
•The frequency inverters must be transported and stored in an appropriate way. During transport
and storage the devices must remain in their original packaging.
•The units may only be stored in dry rooms which are protected against dust and moisture and are
exposed to little temperature deviations only. The requirements of DIN EN 60721-3-1 for storage,
DIN EN 60721-3-2 for transport and labeling on the packaging must be met.
•The duration of storage without connection to the permissible nominal voltage may not exceed
one year.
2.10.4 Handling and installation
•Do not commission any damaged or destroyed components.
•Prevent any mechanical overloading of the frequency inverter. Do not bend any components and
never change the isolation distances.
•Do not touch any electronic construction elements and contacts. The frequency inverter is
equipped with components which are sensitive to electrostatic energy and can be damaged if
handled improperly. Any use of damaged or destroyed components will endanger the ma-
chine/plant safety and shall be considered as a non-compliance with the applicable standards.
•Only install the frequency inverter in a suitable operating environment. The frequency inverter is
exclusively designed for installation in industrial environments.
•If seals are removed from the case, this can result in the warranty becoming null and void.
2.10.5 Electrical connections
•The five safety rules must be complied with.
•Never touch live terminals. The DC link may have dangerous voltage levels even up to three
minutes after shutdown.
•When performing any work on/with the frequency inverter, always comply with the applicable
national and international regulations/laws on work on electrical equipment/plants of the country
when the frequency inverter is used.
•The cables connected to the frequency inverters may not be subjected to high-voltage insulation
tests unless appropriate circuitry measures are taken before.
•Only connect the frequency inverter to suitable supply mains.
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2.10.5.1 The five safety rules
When working on/in electrical plants, always follow the five safety rules:
1. Isolate
2. Secure to prevent restarting
3. Check isolation
4. Earth and short-circuit,
5. Cover or shield neighboring live parts.
2.10.6 Safe operation
•During operation of the frequency inverter, always comply with the applicable national and inter-
national regulations/laws on work on electrical equipment/plants.
•Before commissioning and the start of the operation, make sure to fix all covers and check the
terminals. Check the additional monitoring and protective devices according to the applicable na-
tional and international safety directives.
•During operation, never open the machine/plant
•Do not connect/disconnect any components/equipment during operation.
•The machine/plant holds high voltage levels during operation, is equipped with rotating parts
(fan) and has hot surfaces. Any unauthorized removal of covers, improper use, wrong installation
or operation may result in serious injuries or material damage.
•Some components, e.g. the heat sink or brake resistor, may be hot even some time after the ma-
chine/plant was shut down. Don't touch any surfaces directly after shutdown. Wear safety gloves
where necessary.
•The frequency inverter may hold dangerous voltage levels until the capacitor in the DC link is dis-
charged. Wait for at least 3 minutes after shutdown before starting electrical or mechanical work
on the frequency inverter. Even after this waiting time, make sure that the equipment is deener-
gized in accordance with the safety rules before starting the work.
•In order to avoid accidents or damage, only qualified staff and electricians may carry out the work
such as installation, commissioning or setup.
•In the case of a defect of terminals and/or cables, immediately disconnect the frequency inverter
from mains supply.
•Persons not familiar with the operation of frequency inverters must not have access to the fre-
quency inverter. Do not bypass nor decommission any protective facilities.
•The frequency inverter may be connected to power supply every 60 s. This must be considered
when operating a mains contactor in jog operation mode. For commissioning or after an emer-
gency switch-off, a non-recurrent, direct restart is permissible.
•After a failure and restoration of the power supply, the motor may start unexpectedly if the Auto
Start function is activated.
If staff is endangered, a restart of the motor must be prevented by means of external circuitry.
•Before commissioning and the start of the operation, make sure to fix all covers and check the
terminals. Check the additional monitoring and protective devices according to EN 60204 and ap-
plicable the safety directives (e.g. Working Machines Act or Accident Prevention Directives).
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2.10.7 Maintenance and service/troubleshooting
•Visually inspect the frequency inverter when carrying out the required maintenance work and
inspections at the machine/plant.
•Perform the maintenance work and inspections prescribed for the machine carefully, including the
specifications on parts/equipment replacement.
•Work on the electrical components may only be performed by a qualified electrician according to
the applicable rules of electrical engineering. Only use original spare parts.
•Unauthorized opening and improper interventions in the machine/plant can lead to personal injury
or material damage. Repairs on the frequency inverters may only be carried out by the manufac-
turer or persons authorized by the manufacturer. Check protective equipment regularly.
•Before performing any maintenance work, the machine/plant must be disconnected from mains
supply and secured against restarting. The five safety rules must be complied with.
2.10.8 Final decommissioning
Unless separate return or disposal agreements were made, recycle the disassembled frequency in-
verter components:
•Scrap metal materials
•Recycle plastic elements
•Sort and dispose of other component materials
Electric scrap, electronic components, lubricants and other utility materials must be
treated as special waste an
d may only be disposed of by specialized companies.
In any case, comply with any applicable national disposal regulations as regards envi-
ronmentally compatible disposal of the frequency inverter. For more details, contact
the competent local authorities.
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3Safety Instructions on Function „Safe Torque Off“ (STO)
The function “Safe Torque Off” (STO) is a functional safety provision, i.e. it protects
staff from damage, provided that projecting, installation and
operation are performed
properly. This function does not disconnect the plant from power supply.
The safety function “Safe torque off” (STO) can be used to realize an “Emergency
Stop” according to EN 60204 while the power supply is still active on the f
requency
inverter
A provision must be provided for disconnecting the machine from power supply for
maintenance work.
WARNING
Improper installation of the safety technique can cause an uncontrolled starting of the
drive. This may cause death, serious injuries and significant material damage.
Safety functions may only be installed and commissioned by qualified staff.
The Standard EN 60204 separates EMERGENCY SWITCH OFF and EMERGENCY STOP.
EMERGENCY SWITCH OFF means the electrical disconnection of the frequency invert-
er from the supply source. An EMERGENCY SWITCH OFF
can be realized by installing
a switch disconnector in example.
EMERGENCY STOP provides the possibility to achieve a safe state of the
frequency
inverter while maintaining the supply voltage.
Depending on the application, other components may be necessary to achieve
a safe
state in addition to “Safe Torque Off (STO)” of the frequency inverter.
An EMERGENCY STOP according to EN 60204 must be functi
oning in all operation
modes of the application.
Resetting of an EMERGENCY STOP or an EMERGENCY SWITCH OFF
must not result in
uncontrolled starting of the drive.
The drive is started again when the function STO is no longer triggered. In order to
comply with EN
60204, it must be ensured by taking external measures that the drive
does not start without prior confirmation.
Without a mechanical brake, the drive might not stop immediately but coast to a
standstill. If this may result in personal or material
damage, additional safety
measures must be taken.
If persons may be endangered after disconnection of the motor control by STO, ac-
cess to the hazard areas must be prevented until the drive has stopped.
Check the safety function at regular intervals
according to the results of your risk
assessment. BONFIGLIOLI VECTRON recommends that the check is performed after
one year, at the latest.
The STO function is one fault fail-safe. No single fault or component failure can cause
a disabled drive to produce motor shaft torque. Only in extremely unlike combinations
of component faults the motor shaft could move jerky with sudden acceleration (max-
imum 180°/number of pole pairs, for example jerky movement of 90° for 4-pole mo-
tor, 180°/2) and produce torque. It must be checked if this behavior can cause a
dangerous machine movement.
If the STO function is used, the special safety, installation and instructions on use
instructions shall be complied with.
Comply with the Application manual „Safe Torque Off STO“, especially when the de-
scribed safety relevant function is used.
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Warning! Dangerous voltage!
After disconnection of an external DC 24 V power supply, the DC link of the frequency
inverter is still connected to mains supply.
Even if the motor control is deactivated and the motor is coasting to a standstill or
has already stopped, high voltages may still be present on the motor terminals.
Before working (e.g. maintenance) on live parts, the machine must always be discon-
nected from mains supply (main switch). This must be documented on the machine.
When the function “Safe Torque Off” is triggered, the motor is not isolated from the
DC link of the frequency inverter. High voltage levels may be present at the motor.
Do not touch live terminals.
Permanent magnet synchronous motors (PMSM) must be operated only up to
the
synchronous speed. PMSM cannot be operated above the synchronous speed be-
cause the trigger of the STO function can lead to the destruction of the power stage.
3.1 Approved Devices
All ACU devices of sizes 1 to 7 are approved for applications with functional safety according to this
manual.
For ACU of size 8 the certification of the function “Safe Torque Off” is in preparation.
The information of the size you can refer to the operating manual and the Quick Start Guide.
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4Information of Risk Analysis and Risk Assessment
According to the Directive on Machinery 98/37/EC, the manufacturer of a machine is obliged to carry
out a risk analysis in order to identify the hazards related to the machine.
The Standard EN 14121-1 – Safety of machinery - Risk assessment – Principles – describes the infor-
mation required for risk assessment.
Risk assessment is effected according to the following criteria:
−degree of injury (serious/minor)
−frequency or duration of stay (frequent/seldom)
−possibilities of avoidance (hardly possible/possible)
For defined risks the Standards EN ISO 13849-1, IEC 61508 or EN 954-1 can be used to accomplish a
correct classification into Safety category, SIL (Safety Integrated Level) or PL (Performance Level).
These standards contain design principles for safety-relevant parts of control systems.
In the case of the safety function “Safe Torque Off”, the risk assessment must consider the fact that
the motor will coast to a standstill in the case of an error. Depending on the application, a mechanical
brake may be required.
Responsibility:
The Manufacturer shall be responsible for the safety of the machine.
−risk analysis of hazards originating from the machine
−measures for reduction and elimination of the risks
−documentation of residual risk from the point of view of the manufacturer
−selection of suitable controller, installation of protective equipment, ergonomics, documentation,
warning of remaining risks
The operator of the machine is responsible for the safety of the application.
−risk analysis of hazards originating from the use of the machine
−documentation of residual risk from the point of view of the operator
−safe operation and protection of operating staff (barriers, instruction of operating staff, etc.)
Selection of safety function:
−Risk analysis and risk assessment for machine (standards EN 12100-1, EN 12100-2 and EN 14121-
1)
−Risk reduction by machine design
−If not possible by design: risk reduction by protective equipment
−Identification of safety requirements
−Selection of category of safety function
- PL d according to EN ISO 13849-1
- SIL 2 according to IEC 61508
- Category 3 according to EN 954-1
The Standard EN954-1 was replaced by the legislator with the standard
EN
ISO 13849-1.
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5General Description of Safety Function
5.1 Integrated Safety Function
Electronic protection systems are integrated in the drive control system and perform safety functions
in order to minimize or eliminate hazards caused by functional errors of machines.
The integrated safety functions replace time-consuming and expensive installation of external safety
components.
The safety function can be requested or triggered by an error.
In hazard areas, setup work or work for elimination or errors may be required where the safety func-
tion is not to be activated by isolating protection devices such as mains contactors or motor contac-
tors. Here, the additional safety function may be used. STO can be used as an alternative to mains or
motor contactors, which can be omitted dependent on the application.
The integrated safety functions reduce the risk of personal damage in hazard areas and reduce instal-
lation requirements.
5.2 Functional Safety
The safety function of the control system must be ensured for normal, trouble-free operating sates as
well as in the case of an error. As a result of this requirement:
−The safety function must be checked in case errors are present. Possible methods include: error
tree analysis, FMEA, etc.).
5.3 Classification the safety requirement
The integrated safety function “Safe Torque Off” of the ACU frequency inverter meets the following
requirements:
−up to safety integrity level SIL 2 according to DIN EN 61508 for STO (STO, Safe Torque Off ac-
cording to EN 61800-5-2)
−of category 3 according to DIN EN 954-1 (safe stop)
−up to performance level d according to EN 13849-1
In the case of an error, thanks to the safety function STO, the frequency inverter does not supply
energy to the motor which would cause a revolution or torque (or a movement or force in the case of
a linear motor).
Characteristic for the classification mentioned above:
−If an error occurs, the safety function is maintained.
−
By using appropriate safety control devices, stop category 0 and stop category 1 according to EN
60204 can be achieved in the machine. For safety control devices, please refer to chapter 10.
Stop category 0: Stop by immediate disconnection of energy supply to the machine drive elements,
i.e. uncontrolled stop.
Stop category 1: Controlled stop, where energy is still being supplied to the drive elements of the
machine to perform the stopping operation. Energy supply is stopped only after the drive has come to
a standstill.
Note that the drive may not stop immediately but coast to a standstill. If no mechanical brake is in-
stalled, or a defective brake may involve a risk, further protective measures (in example tumbler) are
to be taken.
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