Festo CMTT-AS S1 Series Operating and installation instructions

8096255
CMMT-AS-...-S1
Servo drive
8096255
2018-10a
[8096257]
Description| Safety
sub-function| STO,
SBC, SS1

Translation of the original instructions
ET 200SP®, PNOZ®, Pilz®, SIEMENS® are registered trademarks of the respective trademark owners in
certain countries.
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3Festo — CMMT-AS-...-S1 — 2018-10a
1 About this document................................................................................................... 5
1.1 Target group................................................................................................................. 5
1.2 Applicable documents.................................................................................................. 5
1.3 Product version............................................................................................................ 5
1.4 Product labelling.......................................................................................................... 5
1.5 Specified standards...................................................................................................... 5
2 Safety........................................................................................................................... 5
2.1 Safety instructions........................................................................................................ 5
2.2 Intended use................................................................................................................ 6
2.2.1 Application areas....................................................................................................6
2.2.2 Permissible components.........................................................................................6
2.3 Foreseeable misuse...................................................................................................... 6
2.4 Training of qualified personnel..................................................................................... 7
2.5 Approvals and certifications......................................................................................... 7
3 Service..........................................................................................................................7
4 Product overview......................................................................................................... 8
4.1 Safety sub-functions..................................................................................................... 8
4.1.1 Function and application.........................................................................................8
4.1.2 Safety sub-function STO......................................................................................... 8
4.1.3 Safety sub-function SBC......................................................................................... 12
4.1.4 Safety sub-function SS1..........................................................................................16
4.1.5 Cross wiring of several servo drives........................................................................20
4.1.6 Error exclusion........................................................................................................20
4.1.7 Safety relay unit......................................................................................................21
4.1.8 Interfaces of the PDS.............................................................................................. 21
5 Installation.................................................................................................................. 22
5.1 Safety............................................................................................................................ 22
5.2 STO installation............................................................................................................ 23
5.3 SBC installation............................................................................................................ 24
5.4 SS1 installation............................................................................................................ 26
5.5 Installation for operation without safety sub-function...................................................27
6 Commissioning............................................................................................................ 28
6.1 Safety............................................................................................................................ 28
6.2 Check lists.................................................................................................................... 28
7 Operation..................................................................................................................... 30
8 Malfunctions............................................................................................................... 31
8.1 Diagnostics via LED...................................................................................................... 31
8.2 Repair............................................................................................................................31
9 Technical data............................................................................................................. 32
9.1 Technical data, safety equipment................................................................................. 32
Table of contents

9.2 Technical data, product conformity and approvals........................................................ 36
9.3 General technical data...................................................................................................36
9.4 Technical data, electrical............................................................................................... 38
9.4.1 Motor auxiliary connection [X6B]........................................................................... 38
9.4.2 Inputs, outputs, ready contact at [X1A].................................................................. 40
9.4.3 Inputs and outputs for the axis [X1C]..................................................................... 43
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1 About this document
1.1 Target group
The document is targeted towards individuals who mount and operate the product. It is additionally
targeted towards individuals who are entrusted with the planning and application of the product in a
safety-oriented system.
1.2 Applicable documents
This document describes the use of the safety sub-functions Safe torque off (STO) and Safe brake con-
trol (SBC) in accordance with EN61800-5-2.
It is possible to implement the safety sub-function Safe stop 1 (SS1) with a suitable external safety
relay unit and appropriate wiring of the servo drive.
• Observe the safety instructions in the documentation è Instructions Assembly Installation
Safety sub-function.
All available documents for the product èwww.festo.com/pk.
1.3 Product version
This documentation refers to the following version of the device:
– Servo drive CMMT-AS-...-S1, revision R01 and higher, see product labelling
1.4 Product labelling
Product labelling èDescription Assembly, Installation.
1.5 Specified standards
Version
EN61131-2:2007 ENISO 13849-1:2015
IEC61800-5-1:2016 EN61508 Parts 1-7:2010
EN61800-3:2004+A1:2012 EN60204-1:2006+A1:2009+AC2010
EN61800-5-2:2017 EN62061:2005+AC:2010+A1:2013+A2:2015
EN 61800-2:2015 –
Tab. 1 Standards specified in the document
2 Safety
2.1 Safety instructions
It is only possible to determine whether the product is suitable for specific applications by also
assessing further components of the subsystem.
Analyse and validate safety function of the entire system.
About this document

The safety functions are to be checked at adequate intervals for proper functioning. Selecting the type
of test and time intervals within the stated time period is the responsibility of the operator. The check
is to be conducted such that flawless functioning of the safety device can be verified in interaction
with all components. Time period for cyclical test è 9.1 Technical data, safety equipment.
Prior to initial commissioning, wire the control inputs of the safety sub-functions STO and SBC. The
safety sub-functions STO and SBC are available on the CMMT-AS on delivery without the need for any
additional parameterisation.
Keep the documentation somewhere safe throughout the entire product lifecycle.
2.2 Intended use
The CMMT-AS-...-S1 supports the following safety sub-functions in accordance with EN61800-5-2:
– Safe torque off (STO)
– Safe brake control (SBC)
– Safe stop 1 (SS1), achievable with suitable safety relay unit and appropriate wiring of the servo
drive
The safety sub-function STO is intended to disconnect the torque of the connected motor, thereby pre-
venting an unexpected restart of the motor.
The safety sub-function SBC is intended to safely hold the motor and axis in position at standstill.
The safety sub-function SS1 is intended for performing a rapid stop with subsequent torque switch-
off.
2.2.1 Application areas
Safety sub-functions may only be used for applications for which the stated safety reference values
are sufficient è 9.1 Technical data, safety equipment.
2.2.2 Permissible components
The logic supply must meet the requirements of EN60204-1 (protective extra-low voltage, PELV).
If holding brakes and clamping units without certification are used, the suitability for the related
safety-oriented application must be determined through a risk assessment.
The motors must fulfil the requirements of EN61800-5-2 appendix D.3.5 and D.3.6 and of
EN60204-1. Motors approved or specified by Festo for the CMMT-AS fulfil the requirements.
The motor cables and brake lines must fulfil the requirements of EN61800-5-2 appendix D.3.1 and of
EN60204-1. Motor cables and brake lines approved by Festo for the CMMT-AS fulfil the requirements.
2.3 Foreseeable misuse
Foreseeable misuse, general
– Use outside the limits of the product defined in the technical data.
– Cross-wiring of the I/O signals of more than 10 servo drives CMMT-AS.
– Use in IT networks without insulation monitors for detection of earth faults.
If the device is operated in IT networks, the potential conditions will change in the event of a fault
(earth fault on the feeding mains supply). As a result, the rated voltage of 300V to PE – which has
important implications for the design of insulation and network disconnection – will be exceeded.
This error must be detected.
Safety
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– Use of a diagnostic output for connection of a safety function.
The diagnostic outputs STA and SBA are not part of the safety circuit. The diagnostic outputs are
used to improve diagnostic coverage of the related safety sub-function. The diagnostic outputs
may only be used in combination with the related safe control signals (AND operation) plus a reli-
able time monitoring function in the safety relay unit for the purpose of switching additional
safety-critical functions.
Foreseeable misuse of the safety sub-function STO
– Use of the STO function without external measures for drive axis influenced by external torques.
If external torques influence the drive axis, use of the safety sub-function STO on its own is not
suitable for stopping the axis safely. Additional measures are required to prevent dangerous
movements of the drive axis, such asuse of a mechanical brake in combination with the safety
sub-function SBC.
– Disconnection of the motor from the power supply.
The safety sub-function STO does not disconnect the drive from the power supply as defined by
electrical safety.
Foreseeable misuse of the safety sub-function SBC
– Use of an unsuitable holding brake or clamping unit, also in view of:
– Holding or brake torque and emergency brake characteristics, if required.
– Frequency of actuation
– Use of an unsuitable logic voltage supply
2.4 Training of qualified personnel
The product may be installed and placed in operation only by a qualified electro technician, who is
familiar with the topics:
– installation and operation of electrical control systems
– applicable regulations for operating safety-engineering systems
Work on safety-related systems may only be carried out by qualified personnel trained in safety engin-
eering.
2.5 Approvals and certifications
The product has the CE marking. For details of directives, see
è 9.2 Technical data, product conformity and approvals.
The product-related EU directives and standards are listed in the declaration of conformity
èwww.festo.com/sp.
The product is a safety device in accordance with the Machinery Directive. For details of the safety-ori-
ented standards and test values that the product complies with and fulfils, see
è 9.1 Technical data, safety equipment. Please note that compliance with the named standards is
limited to the CMMT-AS-...-S1.
3 Service
Contact your regional Festo contact person if you have technical questions èwww.festo.com.
Service
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4 Product overview
4.1 Safety sub-functions
4.1.1 Function and application
The servo drive CMMT-AS-...-S1 has the following safety-related performance features:
– Safe torque off (STO)
– Safe brake control (SBC)
– Safe stop 1 (SS1) with use of a suitable external safety relay unit and appropriate wiring of the
servo drive
– Diagnostic outputs STA and SBA for feedback of the active safety sub-function
4.1.2 Safety sub-function STO
Fig. 1 Symbol for STO
The function described here implements the safety sub-function STO according to EN61800-5-2 (cor-
responds to stop category 0 from EN60204-1).
The safety sub-function STO is used when the energy supply to the motor needs to be switched off
safely in the application but there are no further requirements for a targeted standstill of the drive
(such asstop category 1 from EN60204-1 èSafety sub-function SS1).
Function and application of STO
The safety sub-function STO switches off the driver supply for the power semiconductor, thus prevent-
ing the power output stage from supplying the energy required by the motor. The power supply to the
drive is safely disconnected when the safety sub-function STO is active. The drive cannot generate
torque and so cannot perform any hazardous movements. With suspended loads or other external
forces, additional measures must be taken to prevent movements being performed (e.g.mechanical
clamping units). In the STO state, the standstill position is not monitored.
The machines must be stopped and locked in a safe manner. This especially applies to vertical axes
without automatic locking mechanics, clamping units or counterbalancing.
NOTICE!
If there are multiple errors in the servo drive, there is a danger that the drive will move. Failure of the
servo drive output stage during the STO status (simultaneous short circuit of 2 power semiconductors
in different phases) may result in a limited detent movement of the rotor. The rotation angle/travel
corresponds to a pole pitch. Examples:
•Rotating motor, synchronous machine, 8-pin è Movement <45° at the motor shaft
•Linear motor, pole pitch 20mm èMovement <20mm at the moving part
Product overview
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Functional principle of STO
Fig. 2 Functional principle of STO
1High-side output stage
2Low-side output stage
3Intermediate circuit voltage
Fig. 3 Output stage with power transistors
STO request
The safety sub-function STO is requested on 2 channels by simultaneously switching off the control
voltage at both control inputs #STO-A and #STO-B.
The drive behaves as follows when the safety sub-function STO is requested:
Product overview
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– Behaviour of the drive with a running motor: The movement of the drive is not decelerated via a
braking ramp. The drive continues to move uncontrolled due to inertia or external forces until it
comes to a standstill by itself.
– Behaviour of the drive with a stopped motor: The drive is uncontrolled and can be moved through
external forces.
STO feedback via STA diagnostic contact
The status of the safety sub-function STO can be reported to the safety relay unit via the STA diagnost-
ic output.
The STA diagnostic output indicates whether the safe status has been reached for the safety sub-func-
tion STO. The STA diagnostic output switches to high level only when STO is active on 2 channels via
the control inputs #STO-A and #STO-B.
#STO-A #STO-B STA
Low level Low level High level
Low level High level Low level
High level Low level Low level
High level High level Low level
Tab. 2 Level of STA
If protective functions are triggered on both channels (STO-A and STO-B), e.g.if the voltage at STO-A
and STO-B is too high, the internal protective functions switch off and STA likewise delivers a high
level signal.
Recommendation: The safety relay unit should check the status of the diagnostic output whenever
there is a STO request. The level of STA must change according to the logic table. The safety relay unit
can cyclically test the signals #STO-A and #STO-B for high level with low test pulses and for low level
with high test pulses.
Product overview
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Timing of STO
Fig. 4 STO timing diagram
Legend for STO timing
Term/abbreviation Explanation
#STO-A/#STO-B 2-channel input for STO request
#STO-HS/#STO-LS Internal triggering, PWM driver high side/low side
tSTO,TP Length, low test pulses1) at #STO-A/B
tSTO,In Max. delay until STO shutdown is performed (≤permissible reaction time
when a safety sub-function is requested1))
Product overview
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Term/abbreviation Explanation
STA Feedback, STO active
tSTA,Out Max. delay for diagnostic feedback (≤permissible reaction time when a
safety sub-function is requested1) + 10ms)
n Rotational speed
1) See Technical data, safety reference data for STO
Tab. 3 Legend for STO timing
4.1.3 Safety sub-function SBC
Fig. 5 Symbol for SBC
The function described here implements the safety sub-function SBC according to EN61800-5-2.
The safety sub-function SBC is used for controlling a holding brake in the motor and a clamping unit or
brake on the axis to slow an axis down mechanically or stop it safely.
Function and application of SBC
The safety sub-function SBC provides safe output signals for the control of brakes (holding brakes or
clamping units). The brakes are controlled on 2 channels by switching off the voltage at the following
outputs:
– Safe output BR+/BR– [X6B] for the holding brake of the motor
– Safe output BR-EXT/GND [X1C] for the external brake/clamping unit
The holding brake and/or clamping unit engage and slow the motor or axis. The purpose of this is to
slow down dangerous movements by mechanical means. The braking time is dependent on how
quickly the brake engages and how high the energy level is in the system.
The use of just one brake is only possible when performance requirements are low
è Tab. 16 Safety reference data for the safety sub-function SBC. To do this, connect the brake either
to BR+/BR– or to BR-EXT.
NOTICE!
If there are suspended loads, they usually drop if SBC is requested simultaneously with STO. This can
be traced back to the mechanical inertia of the holding brake or clamping unit and is thus unavoid-
able. Check whether safety sub-function SS1 is better suited to your application.
SBC may only be used for holding brakes or clamping units which engage in the de-energised state.
Ensure the lines are installed in a protected manner.
Product overview
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Functional principle of SBC
Fig. 6 Functional principle of SBC
SBC request
The safety sub-function SBC is requested on 2 channels by simultaneously switching off the control
voltage at both control inputs #SBC-A and #SBC-B:
– The #SBC-A request switches off the power to the signals BR+/BR-.
– The #SBC-B request switches off the power to the signal BR-EXT.
In the event of a power failure in the logic voltage supply of the servo drive, power is also cut off to the
brake outputs.
If SBC is requested and subsequently cancelled, the safe brake control is only re-energised when the
functional micro controller enables the holding brake. This ensures that z-axes with a suspended load
can be restarted without the load dropping.
SBC feedback via SBA diagnostic contact
The 2-channel switching of the brake is indicated via the SBA output. SBA is used to report the status
of the safety sub-function SBC for diagnostic purposes, e.g.by reporting it to an external safety relay
unit.
The SBA diagnostic output indicates whether the safe status has been reached for the safety sub-func-
tion SBC. It is set if the following two conditions are fulfilled:
– Switching off of both brake outputs is requested (#SBC-A = #SBC-B = low level)
– The internal diagnostic functions have determined that there is no internal error and both brake
outputs are de-energised (switched off).
Product overview
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Test pulses that occur simultaneously at SBC-A and SBC-B are not filtered. For this reason, the SBA
diagnostic output delivers a high level signal for the duration of these low test pulses.
Testing the safety sub-function SBC
Test inputs #SBC-A and #SBC-B separately from each other and together. The diagnostic feedback
may only be set to high level when inputs #SBC-A and #SBC-B are both requested. If the signal beha-
viour does not correspond to expectations, the system must be put into a safe condition within the
reaction time. It is essential that time monitoring be provided in the safety relay unit.
The safety sub-function SBC with feedback via SBA must be tested at least 1x within the space of 24h.
• Test SBA feedback based on the SBC-A and SBC-B level according to the following table.
#SBC-A (BR+) #SBC-B (BR-Ext) SBA
Low level Low level High level
Low level High level Low level
High level Low level Low level
High level High level Low level
Tab. 4 Testing all SBC levels
While you are testing the safety sub-function SBC, discrepancy error detection may be activated in the
CMMT-AS if the test lasts longer than 200ms. If a corresponding error message is output by the basic
unit, you will need to acknowledge it.
Evaluation of SBA
Recommendation: Evaluation with every actuation.
• Check SBA feedback whenever there is a request.
#SBC-A (BR+) #SBC-B (BR-Ext) SBA
Low level Low level High level
High level High level Low level
Tab. 5 Evaluation of SBC level
Product overview
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Timing of SBC
Fig. 7 SBC timing diagram
Legend for SBC timing
Term/abbreviation Explanation
tBrake Mechanical delay of the brake
#SBC-A/#SBC-B 2-channel input for SBC request
tSBC,TP Length, low test pulses1) at #SBC-A/B
tSBC,In Max. delay until the related brake output is switched off (≤permissible reac-
tion time when a safety sub-function is requested1))
Product overview
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Term/abbreviation Explanation
SBA Feedback, SBC active
tSBA,Out Max. delay for diagnostic feedback (≤permissible reaction time when a
safety sub-function is requested1) + 10ms)
n Rotational speed
1) See Technical data, safety reference data for SBC
Tab. 6 Legend for SBC timing
Requirements for the brakes
• Check the brakes used for suitability for the application.
As a rule, the brakes used are holding brakes. This means the brakes are well suited to keeping the
motor at a standstill.
The internal holding brake of the motor is also used for the safety sub-function SBC. Please be aware
of the following constraints:
– The holding brake must be designed for the load torque to be stopped.
– The specifications for the holding brakes permit a certain amount of movement until the full hold-
ing torque is reached. This must be taken into account in the design of the vertical axes and con-
figuration of the safety sub-function SBC.
– “Reserves” should be factored in when selecting the motor plus holding brake, e.g.operation at
no more than 2/3 of the nominal torque. The holding brakes in the motors are usually designed so
that the motor shaft will come to a standstill without coasting at loads below 70% of the nominal
torque.
– Depending on the hazard situation, the holding brake must be designed with a correspondingly
higher nominal torque.
– When designing the holding brake, the additional load torque for the brake test must be con-
sidered.
The number of clamping and braking applications for the clamping unit is limited due to wear.
1. Observe the corresponding specifications in the data sheet.
2. Replace clamping unit before the maximum number of clamping applications is reached.
3. Replace clamping unit if the emergency brake features of the clamping unit have to be used. Pay
attention to the number of permissible emergency braking applications.
Brake test
• Check whether a brake test is required. The DGUV information sheet “Gravity-loaded axis”
provides information on this.
4.1.4 Safety sub-function SS1
Fig. 8 Symbol for SS1
The function described here implements the safety sub-function SS1 according to EN61800-5-2.
Product overview
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The safety sub-function SS1 is used when the motor needs to be braked and the energy supply to the
motor then has to be safely switched off in the application but there are no further requirements for a
targeted standstill of the drive (controlled stop, stop category 1 according to EN60204-1).
Together with a suitable safety relay unit, the following can be achieved:
– Safe stop 1 time controlled (SS1-t); triggering of motor deceleration and, after an application-spe-
cific time delay, triggering of the safety sub-function STO
Requirements of SS1
– For details of how to wire the safety sub-function STO, see è Fig.13.
– Execute emergency stop command by means of the safety relay unit (either directly by wiring
CTRL-EN accordingly or indirectly via a further functional controller).
– The time for executing an emergency stop is known.
– The safety relay unit supports programmable timers and simple logic elements.
Function and application of SS1
The procedure for triggering SS1-t comprises the following steps:
1. Functional emergency stop requested (e.g.set input CTRL-EN to low level).
This causes the servo drive to trigger a braking ramp function and – if present – allows the brake
function to engage at the end of the braking ramp. On completion of the braking ramp and once
the parameterisable delay time for brake closing has elapsed, the output stage is functionally
switched off.
2. Start of a time-delay element for actuation of STO.
Select the delay time such that the functional braking ramp is completed in normal operation, the
holding brake function is engaged, and the output stage is functionally switched off. Otherwise,
the axis may drop if STO is triggered concurrently with the brake engagement time that is required
for mechanical reasons. If the brake is engaged while the axis is still in motion, increased wear will
occur on the holding brake (only permitted for emergency braking).
3. Safety sub-function STO requested plus – if required – SBC once the delay time has elapsed.
The figure below shows the necessary logic circuit for the safety relay unit:
Logic in the safety relay unit for SS1
Product overview
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Fig. 9 Logic in the safety relay unit for SS1
The delay times are directly included in the reaction time of the system.
SS1 feedback
The STA signal can be used as feedback for the safety sub-function SS1.
Product overview
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Timing of SS1
Fig. 10 Timing diagram SS1
Legend for SS1 timing
Term/abbreviation Explanation
Timer Delay element in safety relay unit
CTRL-EN Enable signal
tDelay Delay time until STO and SBC are requested (drive has safely come to a
standstill and brake is closed)
#STO-A/B 2-channel input for STO request
#SBC-A/B 2-channel input for SBC request
STA Feedback, STO active
SBA Feedback, SBC active
t1Braking ramp followed, rotational speed = 0 (functionally)
t2Brake closed, and output stage switched off (functionally)
n Rotational speed
Tab. 7 Legend for SS1 timing
Product overview
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SBC request
If there are suspended loads, they usually drop if STO and SBC are requested directly before the brak-
ing ramp is completed because the engagement time of the holding brakes plays a significant role.
For details of how to wire up safety sub-function STO with SBC, see è Fig.14.
• When selecting the delay time tDelay, make sure it is long enough to take account of the maximum
braking ramp time and brake engagement time.
4.1.5 Cross wiring of several servo drives
For cross wiring, wire the diagnostic outputs as a ring. Route both ends of the ring to a 2-channel input
of the safety relay unit. The safety relay unit monitors for discrepancies. A maximum of 10 servo drives
can be wired in parallel.
Cross-wiring, example STA
Fig. 11 Cross-wiring, example STA
For cross-wired diagnostic outputs, the condensed state results from a logical AND link. An output of a
CMMT-AS is capable of pulling all other outputs to low signal. A high signal is present at the two
inputs of the safety relay unit only if all diagnostic outputs deliver high signals. The ring-shaped cross
wiring of the diagnostic outputs with sensing at the beginning and end of the signal chain makes it
possible to detect cable breaks in the cross wiring.
At this point, the diagnostic outputs deviate from the closed current principle. Cyclical automatic test-
ing of the diagnostic output by the safety relay unit is therefore highly recommended
è STO feedback via STA diagnostic contactand è SBC feedback via SBA diagnostic contact.
4.1.6 Error exclusion
Put suitable measures in place to prevent wiring errors:
Product overview
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