SICK AHS36 IO-Link User manual

OPERATING INSTRUCTIONS
AHS/AHM36 CANopen
AHS/AHM36 CANopen Inox
Absolute Encoder

Described product
AHS/AHM36 CANopen
AHS/AHM36 CANopen Inox
Manufacturer
SICK AG
Erwin-Sick-Str. 1
79183 Waldkirch
Germany
Legal information
This work is protected by copyright. Any rights derived from the copyright shall be
reserved for SICK AG. Reproduction of this document or parts of this document is
only permissible within the limits of the legal determination of Copyright Law. Any modi‐
fication, abridgment or translation of this document is prohibited without the express
written permission of SICK AG.
The trademarks stated in this document are the property of their respective owner.
© SICK AG. All rights reserved.
Original document
This document is an original document of SICK AG.
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Contents
1 About this document........................................................................ 6
1.1 Scope......................................................................................................... 6
1.2 Function of this document....................................................................... 6
1.3 Target group.............................................................................................. 6
1.4 Information depth..................................................................................... 6
1.5 Symbols used............................................................................................ 7
1.6 Abbreviations used................................................................................... 7
2 Safety information............................................................................ 9
2.1 Authorized personnel................................................................................ 9
2.2 Intended use............................................................................................. 9
2.3 General safety notes and protective measures...................................... 10
2.4 Environmental protection......................................................................... 10
3 Quick start instructions on the AHS/AHM36 CANopen and
AHS/AHM36 CANopen Inox............................................................. 11
3.1 Node ID/Baud rate................................................................................... 11
3.2 Parameterization....................................................................................... 12
3.2.1 EDS file..................................................................................... 12
3.2.2 Save or restore parameters.................................................... 12
3.3 Process data objects (PDOs).................................................................... 13
3.3.1 PDO communication................................................................ 13
3.3.2 PDO mapping........................................................................... 13
4 Product description........................................................................... 14
4.1 Special features........................................................................................ 14
4.2 Operating principle of the encoder.......................................................... 15
4.2.1 Scaleable resolution................................................................ 15
4.2.2 Preset function......................................................................... 15
4.2.3 Round axis functionality.......................................................... 16
4.2.4 Electronic cam mechanism..................................................... 18
4.3 Controls and status indicators................................................................. 18
5 Integration in CANopen.................................................................... 19
5.1 Communication profile............................................................................. 19
5.1.1 CANopen in the OSI model...................................................... 19
5.1.2 Communication channels....................................................... 19
5.1.3 Topology................................................................................... 20
5.2 Node IDs and COB-IDs.............................................................................. 20
5.3 Baud rate................................................................................................... 21
5.4 Layer Setting Services (LSS).................................................................... 22
5.5 Network management (NMT)................................................................... 25
5.5.1 CANopen state machine.......................................................... 25
5.5.2 Network Management Services.............................................. 26
CONTENTS
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5.5.3 Boot-up message..................................................................... 27
5.5.4 Node Guarding and Heartbeat................................................ 27
5.6 Service Data Objects (SDO)..................................................................... 29
5.7 Process Data Objects (PDO).................................................................... 30
5.7.1 PDO mapping........................................................................... 31
5.7.2 PDO data transmission........................................................... 31
5.7.3 Asynchronous or synchronous formation of the position...... 33
5.8 Configurable functions............................................................................. 34
5.8.1 EDS file..................................................................................... 34
5.8.2 Scaling parameters................................................................. 35
5.8.3 Preset function......................................................................... 37
5.8.4 Cyclic process data.................................................................. 38
5.8.5 Speed measurement............................................................... 39
5.8.6 Round axis functionality.......................................................... 40
5.8.7 Electronic cam mechanism..................................................... 41
6 Object library...................................................................................... 44
6.1 Nomenclature........................................................................................... 44
6.2 Standard objects...................................................................................... 44
6.2.1 Detailed information on the standard objects....................... 45
6.3 Process Data Objects............................................................................... 50
6.3.1 Basic PDO structure................................................................. 51
6.3.2 Parameter of the Receive PDO............................................... 51
6.3.3 Parameter of the Transmit PDOs............................................ 52
6.3.4 Transmission types.................................................................. 54
6.3.5 Objects and their subindices that can be mapped............... 56
6.4 Encoder profile specific objects............................................................... 57
6.4.1 Encoder parameters................................................................ 58
6.4.2 Objects for the electronic cam mechanism (CAM)................ 60
6.4.3 Objects for diagnostics............................................................ 63
6.5 Manufacturerspecific objects.................................................................. 67
6.5.1 Objects for the encoder configuration.................................... 68
6.5.2 Objects that provide status information................................. 73
7 Commissioning.................................................................................. 82
7.1 Electrical installation................................................................................ 82
7.1.1 Connection of the AHS/AHM36 CANopen and AHS/
AHM36 CANopen Inox............................................................. 82
7.2 Settings on the hardware......................................................................... 83
7.3 Configuration............................................................................................. 83
7.3.1 Default delivery status............................................................. 83
7.3.2 System configuration............................................................... 84
7.4 Tests before the initial commissioning.................................................... 88
8 Fault diagnosis................................................................................... 89
8.1 In the event of faults or errors................................................................. 89
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8.2 Support...................................................................................................... 89
8.3 Error and status indications on the LED................................................. 89
8.3.1 Meaning of the LED displays................................................... 89
8.4 Diagnostics via CANopen......................................................................... 90
8.4.1 Emergency Messages.............................................................. 90
8.4.2 Alarms, warnings and status................................................... 91
8.4.3 Error during the SDO transfer................................................. 91
9 Annex.................................................................................................. 93
9.1 Conformities and certificates................................................................... 93
9.1.1 Compliance with EU directives................................................ 93
9.1.2 Compliance with UK statutory instruments........................... 93
CONTENTS
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1 About this document
Please read this chapter carefully before working with this documentation and the AHS/
AHM36 CANopen und AHS/AHM36 CANopen Inox Absolute Encoder.
1.1 Scope
NOTE
These operating instructions apply to the AHS/AHM36 CANopen and AHS/AHM36
CANopen Inox Absolute Encoder with the following type codes:
•Singleturn-Encoder Basic = AHS36B-xxCx004096
•Multiturn-Encoder Basic = AHM36B-xxCx012x12
•Singleturn-Encoder Advanced = AHS36A-xxCx016384
•Multiturn-Encoder Advanced = AHM36A-xxCx014x12
•Singleturn-Encoder Inox = AHS36I-xxCx016384
•Multiturn-Encoder Inox = AHM36I-xxC-x014x12
1.2 Function of this document
These operating instructions are designed to address the technical personnel of the
machine manufacturer or the machine operator in regards to correct configuration,
electrical installation, commissioning, operation and maintenance of the AHS/AHM36
CANopen und AHS/AHM36 CANopen Inox Absolute Encoder.
1.3 Target group
The operating instructions are addressed at the planners, developers and operators of
systems in which one or more AHS/AHM36 CANopen und AHS/AHM36 CANopen Inox
Absolute Encoder are to be integrated. They also address people who initialize the use
of the AHS/AHM36 CANopen und AHS/AHM36 CANopen Inox or who are in charge of
servicing and maintaining the device.
These instructions are written for trained persons who are responsible for the installa‐
tion, mounting and operation of the AHS/AHM36 CANopen und AHS/AHM36 CANopen
Inox in an industrial environment.
1.4 Information depth
These operating instructions contain information on the AHS/AHM36 CANopen und
AHS/AHM36 CANopen Inox Absolute Encoder on the following subjects:
•product features
•electrical installation
•commissioning and configuration
•fault diagnosis and troubleshooting
•conformity
These operating instructions do not contain any information on the mounting of the
AHS/AHM36 CANopen und AHS/AHM36 CANopen Inox. You will find this information in
the mounting instructions included with the device.
They also do not contain any information on technical specifications, dimensional draw‐
ings, ordering information or accessories. You will find this information in the product
information for the AHS/AHM36 CANopen und AHS/AHM36 CANopen Inox.
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Planning and using measurement systems such as the AHS/AHM36 CANopen and
AHS/AHM36 CANopen Inox also requires specific technical skills beyond the informa‐
tion in the operating instructions and mounting instructions. The information required to
acquire these specific skills is not contained in this document.
When operating the AHS/AHM36 CANopen und AHS/AHM36 CANopen Inox, the
national, local and statutory rules and regulations must be observed.
Additional information
You will find additional information at www.can-cia.org.
1.5 Symbols used
NOTE
Refer to notes for special features of the device.
LED symbols describe the state of a diagnostics LED. Examples:
OThe LED is illuminated constantly.
ôFõ The LED flashes evenly.
ôKõ The LED flashes with a short duty cycle.
oThe LED is off.
bTake action …
Instructions for taking action are shown by an arrow. Read carefully and follow the
instructions for action.
CAUTION
Warning!
A warning notice indicates an actual or potential risk or health hazard. They are
designed to help you to prevent accidents.
Read carefully and follow the warning notices.
1.6 Abbreviations used
CAN Controller Area Network
CANopen® CANopen is a registered trademark of CAN in Automation e.V.
CMR Counts per Measuring Range
CNR_D Customized Number of Revolutions, Divisor = divisor of the customized number of
revolutions
CNR_N Customized Number of Revolutions, Nominator = nominator of the customized number
of revolutions
COB-ID Communication Object Identifier = address of the communication object
CoS Change of State
CPR Counts Per Revolution = resolution per revolution
EDS Electronic Data Sheet
EEPROM Electrically Erasable Programmable Readonly Memory
EMGY Emergency Message
LSS Layer Setting Services = services for the configuration of Node ID and baud rate
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NMT Network Management
Node-ID Node Identifier = node address
PDO Process Data Object
PLC Programmable Logic Controller
PMR Physical Measuring Range
PRS Physical Resolution Span (per revolution)
RTR Remote Transmission Request = request telegram for PDOs
SDO Service Data Object
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2 Safety information
This chapter deals with your own safety and the safety of the equipment operators.
bPlease read this chapter carefully before working with the AHS/AHM36 CANopen
and AHS/AHM36 CANopen Inox or with the machine or system in which the AHS/
AHM36 CANopen and AHS/AHM36 CANopen Inox is used.
2.1 Authorized personnel
The AHS/AHM36 CANopen and AHS/AHM36 CANopen Inox Absolute Encoder must
only be installed, commissioned and serviced by authorized personnel.
NOTE
Repairs to the AHS/AHM36 CANopen and AHS/AHM36 CANopen Inox are only allowed
to be undertaken by trained and authorized service personnel from SICK STEGMANN
GmbH.
The following qualifications are necessary for the various tasks:
Table 1: Authorized personnel
Activity Qualification
Mounting •Basic technical training
•Knowledge of the current safety regulations in the
workplace
Electrical installation and replace‐
ment
•Practical electrical training
•Knowledge of current electrical safety regulations
•Knowledge on the use and operation of devices in
the related application (e.g. industrial robots, storage
and conveyor technology)
Commissioning, operation and con‐
figuration
•Knowledge on the current safety regulations and the
use and operation of devices in the related applica‐
tion
•Knowledge of automation systems
•Knowledge of CANopen®
•Knowledge of automation software
2.2 Intended use
The AHS/AHM36 CANopen and AHS/AHM36 CANopen Inox Absolute Encoder is a
measuring device that is manufactured in accordance with recognized industrial regula‐
tions and meets the quality requirements as per ISO 9001:2008 as well as those of an
environment management system as per ISO 14001:2009.
An encoder is a device for mounting that cannot be used independent of its foreseen
function. For this reason an encoder is not equipped with immediate safe devices.
Measures for the safety of persons and systems must be provided by the constructor of
the system as per statutory regulations.
Due to its design, the AHS/AHM36 CANopen and AHS/AHM36 CANopen Inox can
only be operated within an CANopen® network. It is necessary to comply with the
CANopen® specifications and guidelines for setting up a CANopen® network.
In case of any other usage or modifications to the AHS/AHM36 CANopen and AHS/
AHM36 CANopen Inox, e.g. opening the housing during mounting and electrical instal‐
lation, or in case of modifications to the SICK software, any claims against SICK STEG‐
MANN GmbH under warranty will be rendered void.
SAFETY INFORMATION 2
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2.3 General safety notes and protective measures
CAUTION
Please observe the following procedures in order to ensure the correct and safe use of
the AHS/AHM36 CANopen and AHS/AHM36 CANopen Inox!
The encoder is to be installed and maintained by trained and qualified personnel
with knowledge of electronics, precision mechanics and control system programming.
It is necessary to comply with the related standards covering the technical safety
stipulations.
All safety regulations are to be met by all persons who are installing, operating or
maintaining the device:
•The operating instructions must always be available and must always be followed.
•Unqualified personnel are not allowed to be present in the vicinity of the system
during installation and maintenance.
•The system is to be installed in accordance with the applicable safety stipulations
and the mounting instructions.
•All work safety regulations of the applicable countries are to be followed during
installation.
•Failure to follow all applicable health and work safety regulations may result in
injury or damage to the system.
•The current and voltage sources in the encoder are designed in accordance with
all applicable technical regulations.
2.4 Environmental protection
Please note the following information on disposal.
Table 2: Disposal of the assemblies
Assembly Material Disposal
Packaging Cardboard Waste paper
Shaft Stainless steel Scrap metal
Flange Aluminium / Stainless steel Scrap metal
Housing Aluminium die cast with Zinc
nickel coating / stainless steel
Scrap metal
Electronic assemblies Various Electronic waste
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3 Quick start instructions on the AHS/AHM36 CANopen and AHS/
AHM36 CANopen Inox
3.1 Node ID/Baud rate
The following prerequisites must be met for the communication with the master:
•A correct node ID must be set on the AHS/AHM36 CANopen and AHS/AHM36
CANopen Inox. Correct is:
°a node ID that is not in use in the CANopen network
°a node ID that the master expects
•The same baud rate must be set on the AHS/AHM36 CANopen and AHS/AHM36
CANopen Inox as on the master.
The following parameters are set on the AHS/AHM36 CANopen and AHS/AHM36 CAN‐
open Inox in the factory:
•Node-ID: 5
•Baud rate: 125 kbit/s
Figure 1: Encoder in the CANopen network
The following communication parameters can be assigned to the AHS/AHM36 CAN‐
open and AHS/AHM36 CANopen Inox:
•Node ID: 1 to 127 (as a rule 0 is assigned to the master)
•Baud rate: 10 kbit/s, 20 kbit/s, 50 kbit/s, 100 kbit/s, 125 kbit/s, 250 kbit/s, 500
kbit/s, 800 kbit/s, 1,000 kbit/s
Set the node ID and the baud rate as follows:
•using the manufacturerspecific object 2009h
•using Layer Setting Services see "Baud rate", page 21
Changing node ID and/or baud rate using the object 2009h
To change the node ID and/or the baud rate using the object 2009h, proceed as
follows:
bEntering the access code in object 2009.1h: 98127634h
bChange node ID and/or baud rate in the objects 2009.2h and 2009.3h
bSave parameters with the aid of object 1010.1h: 65766173h (corresponds to
“save” in ASCII)
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NOTE
The changes will only be active after restarting the encoder (switch off and on again the
supply voltage).
Integration of several encoders
bIntegrate encoder 1 in the network and change the node ID (e.g. node ID 4).
bThen integrate encoder 2 in the network and change the node ID if necessary.
NOTE
It is imperative you ensure there are not several encoders or other bus users with an
identical node ID in the same network.
3.2 Parameterization
3.2.1 EDS file
An EDS file is available for the straightforward interfacing of the AHS/AHM36 CANopen
and AHS/AHM36 CANopen Inox to a CANopen master. This file contains, amongst oth‐
ers, the default parameters of the AHS/AHM36 CANopen and AHS/AHM36 CANopen
Inox and the default configuration of the process data.
You can download the EDS file from www.sick.com:
bEnter the sevendigit part number of your encoder directly in the Find field on the
homepage.
bClick the related search result.
A page with all the information and files for your device will open.
bDownload the EDS file.
bIntegrate the EDS file in the engineering tool for your control.
3.2.2 Save or restore parameters
Saving modified parameters in the EEPROM – Save command
All parameters configured in the encoder’s EEPROM are saved using object 1010h.
bFor this purpose enter the command 65766173h (corresponds to “save” in ASCII)
in object 1010.1h.
NOTE
If the Save command is not run, the previous parameters will be loaded from the
EEPROM the next time the encoder is started.
Resetting encoders to default factory settings – Load command
The parameters are reset to the default factory settings using the object 1011h.
bFor this purpose enter the command 64616F6Ch (corresponds to “load” in ASCII)
in the object 1011.1h.
NOTE
The node ID and baud rate set are not in general reset to the default factory settings.
The Save command must be run after the Load command. If the Save command is
not run, the previous parameters will be loaded from the EEPROM the next time the
encoder is started.
3 QUICK START INSTRUCTIONS ON THE AHS/AHM36 CANOPEN AND AHS/AHM36 CANOPEN
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3.3 Process data objects (PDOs)
The AHS/AHM36 CANopen and AHS/AHM36 CANopen Inox supports four Transmit
PDOs and one Receive PDO.
Transmit PDOs
Data are sent by the encoder to the PLC using the four Transmit PDOs.
The four Transmit PDOs are defined by the following objects:
•The objects 1800h … 1803h contain the communication parameters.
•The objects 1A00h … 1A03h contain the mapping of the objects.
The mapping is variable and can be modified.
Receive PDO
Data are received from the PLC by the encoder using the Receive PDO. The mapping for
this Receive PDO is fixed and cannot be modified.
3.3.1 PDO communication
In the factory the transmission type for the Transmit PDOs is set to 255 in the objects
1800h … 1803h. This corresponds to the devicespecific triggering.
NOTE
As an event timer is not configured, the Transmit PDOs are only transferred once on
changing to the Operational status!
Changing factory setting for transmission type
For the cyclic or acyclic output of the Transmit PDOs by the encoder, there are the
following options:
bChange the event timer in the objects 1800h … 1803h see "Parameter of the
Transmit PDOs", page 52.
bConfigure a trigger event using the CoS event handling configuration see
table 121, page 71.
bChange the transmission type in the objects 1800h … 1803h see "Parameter of
the Transmit PDOs", page 52.
Pay attention to the inhibition time
The inhibition time for the PDOs (configured in the objects 1800.3h … 1803.3h) in
principle limits the communication of a device on the CANopen bus. It always has a
higher priority than the event timer, the CoS events and the sync triggering.
If, e.g., the event timer is set to 100 ms and the inhibition time is set to 1 s, the
corresponding PDO is only sent every second.
3.3.2 PDO mapping
You will find which objects are mapped by default in the related transmit PDOs in
section see "Parameter of the Transmit PDOs", page 52.
QUICK START INSTRUCTIONS ON THE AHS/AHM36 CANOPEN AND AHS/AHM36 CANOPEN INOX
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4 Product description
This chapter provides information on the special features and properties of the Abso‐
lute Encoder AHS/AHM36 CANopen und AHS/AHM36 CANopen Inox. It describes the
construction and the operating principle of the device.
bPlease read this chapter before mounting, installing and commissioning the
device.
4.1 Special features
Figure 2: Connection types
Table 3: Special features of the encoder variants
Properties Singleturn
Encoder
Basic
Multiturn
Encoder
Basic
Singleturn
Encoder
Advanced
Multiturn
Encoder
Advanced
Singleturn
Encoder
Inox
Multiturn
Encoder
Inox
CANopen interface C C C C C C
Supports the encoder profile CiA DS406 C C C C C C
Diagnostic functions via CANopen - - C C C C
12 bit singleturn resolution
(1 to 4,096 steps)
C C - - - -
14 bit singleturn resolution
(1 to 16,384 steps)
- - C C C C
12 bit multiturn resolution
(1 to 4,096 revolutions)
-C-C-C
24 bit total resolution - C- - - -
26 bit total resolution - - - C-C
Round axis functionality - - - C-C
Electronic CAM switches - - - C-C
Absolute Encoder in 36 mm design C C C C C C
Electrosensitive, magnetic scanning C C C C C C
Flexible cable outlet/M12 male connector C C C C C C
Large number of mechanical adaptation options C C C C C C
Compact design C C C C C C
Face mount flange, servo flange, blind hollow
shaft
C C C C C C
Stainless steel variant - - - - C C
Enclosure rating IP69K - - - - C C
4 PRODUCT DESCRIPTION
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4.2 Operating principle of the encoder
The sensing system in the AHS/AHM36 CANopen und AHS/AHM36 CANopen Inox AHS/
AHM36 CANopen und AHS/AHM36 CANopen Inox is based on absolute acquisition
of revolutions without an external voltage supply or battery. As a consequence the
encoder can immediately output its absolute position again after switching off and
switching back on.
The AHS/AHM36 CANopen und AHS/AHM36 CANopen Inox acquires the position of
rotating axes and outputs the position in the form of a unique digital numeric value. The
highest reliability is achieved by means of electrosensitive, magnetic scanning.
The AHS36 is a singleturn encoder.
Singleturn encoders are used if absolute acquisition of the rotation of a shaft is
required.
The AHM36 is a multiturn encoder.
Multiturn encoders are used if more than one shaft revolution must be acquired abso‐
lutely.
4.2.1 Scaleable resolution
The resolution per revolution and the total resolution can be scaled and adapted to the
related application.
The resolution per revolution can be scaled in integers from 1 … 4,096 (Basic) or from
1 … 16,384 (Advanced / Inox).
The total resolution of the AHS/AHM36 CANopen und AHS/AHM36 CANopen Inox must
be 2ⁿ times the resolution per revolution. This restriction is not relevant if the round axis
functionality is activated.
4.2.2 Preset function
The position value for an encoder can be set with the aid of a preset value. I.e. the
encoder can be set to any position within the measuring range. In this way, e.g., the
encoder’s zero position can be adjusted to the machine’s zero point.
On switching off the encoder, the offset, the difference between the real position value
and the value defined by the preset, is saved. On switching back on the new preset
value is formed from the new real position value and the offset. Even if the position of
encoder changes while it is switched off, this procedure ensures the correct position
value is still output.
1on switching off
2on switching back on
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4.2.3 Round axis functionality
The encoder supports the function for round axes. The steps per revolution are set as a
fraction. As a result, the total resolution does not have to be configured to 2ⁿ times the
resolution per revolution and can also be a decimal number (e.g. 12.5).
NOTE
The output position value is adjusted with the zero point correction, the counting
direction set and the gearbox parameters entered.
Example with transmission ratio
A rotating table for a filling system is to be controlled. The resolution per revolution
is predefined by the number of filling stations. There are nine filling stations. For the
precise measurement of the distance between two filling stations, 1,000 steps are
required.
Figure 3: Example position measurement on a rotating table with transmission ratio
The number of revolutions is predefined by the transmission ratio = 12.5 of the rotating
table gearing.
The total resolution is then 9 × 1,000 = 9,000 steps, to be realized in 12.5 revolutions
of the encoder. This ratio cannot be realized via the resolution per revolution and the
total resolution, as the total resolution is not 2ⁿ times the resolution per revolution.
The application problem can be solved using the round axis functionality. Here the
resolution per revolution is ignored. The total resolution as well as the nominator and
divisor for the number of revolutions are configured.
9,000 steps are configured as the total resolution.
For the nominator for the number of revolutions 125 is configured, 10 as the divisor
(125/10 = 12.5).
After 12.5 revolutions (that is after one complete revolution of the rotating table) the
encoder reaches the total resolution of 9,000.
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Example without transmission ratio
Figure 4: Example position measurement on a rotating table without transmission ratio
The encoder is mounted directly on the rotating table. The transmission ratio is 1:1.
The rotating table has 9 filling stations. The encoder must be configured such that it
starts to count with 0 at one filling station and counts to 999 on moving to the next
filling station position.
1,000 steps are configured as the total resolution.
For the nominator for the number of revolutions 1 is configured, 9 as the divisor (1/9
revolutions = 1,000).
After 1/9 revolutions of the encoder shaft there are 1,000 steps, then the encoder
starts to count at 0 again.
PRODUCT DESCRIPTION 4
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4.2.4 Electronic cam mechanism
An electronic cam mechanism can be configured using the encoder. Two socalled CAM
channels with up to eight cam switching positions are supported 1 . This is a limit
switch for the position.
Figure 5: Example electronic cam mechanism
Among other parameters, each cam has parameters for the lower switching point 2
and the upper switching point 3, which can be configured via CANopen see "Objects
for the electronic cam mechanism (CAM)", page 60.
4.3 Controls and status indicators
The AHS/AHM36 CANopen und AHS/AHM36 CANopen Inox Absolute Encoder has one
status LED.
LED
Figure 6: Position of the LED
The LED is multicolored. see table 141, page 89 shows the meaning of the signals.
4 PRODUCT DESCRIPTION
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5 Integration in CANopen
5.1 Communication profile
The CANopen communication protocol (documented in CiA DS301) defines how the
devices exchange data with each other in a CANopen network.
5.1.1 CANopen in the OSI model
The CANopen protocol is a standardized layer7 protocol for the CAN bus. This layer is
based on the CAN Application Layer (CAL).
The relevant objects in the encoder profile DS406 are implemented in the AHS/AHM36
CANopen and AHS/AHM36 CANopen Inox see "Objects and their subindices that can be
mapped", page 56.
Figure 7: CANopen in the OSI model
NOTE
Layers 3 … 6 are not used with CANopen.
5.1.2 Communication channels
CANopen has various communication channels (SDO, PDO, Emergency Messages).
These channels are formed with the aid of the Communication Object Identifier
(COBID). The COB-IDs are based on the node IDs for the individual devices on the
CANopen bus see "Node IDs and COB-IDs", page 20.
INTEGRATION IN CANOPEN 5
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Figure 8: Communication channels
•To set the encoder’s node ID, socalled Layer Setting Services (LSS) are used see
"Baud rate", page 21.
•Then communication with the encoder via the Network Management Services
(NMT) is possible see "Network management (NMT)", page 25 and its CANopen
state machine can be switched to the required status (Preoperational, Operational
or Stopped) by the master.
•In the Preoperational status, Service Data Objects (SDO) can be used for commu-
nication and configuration see "Service Data Objects (SDO)", page 29. In the
Operational status, Process Data Objects (PDO) and Emergency Messages (EMGY)
can also be used for communication see "Process Data Objects (PDO)", page 30.
5.1.3 Topology
The AHS/AHM36 CANopen and AHS/AHM36 CANopen Inox is integrated in the CAN‐
open trunk using Tconnectors (the Tconnectors are available as accessories). The trunk
must be terminated at the end using a 120Ohm terminator. In this way reflections are
prevented. This action is not necessary on the stubs to the encoders.
Figure 9: AHx36 in the CANopen topologie
see table 140, page 83 shows the maximum length of the stubs for different baud
rates.
5.2 Node IDs and COB-IDs
The encoder’s node ID can be configured with the aid of the following methods:
5 INTEGRATION IN CANOPEN
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