Drehmo i-matic User manual

MODBUS loop redundant board
for i-matic actuators
Complementary operating manual
for devices with MODBUS loop redundancy
INFORMATION
This installation manual has to be used in conjunction
with the actuator operating manual!
This manual must be kept for future use.

Document history
File revision
Date
Changes
0 2009-11-15 First release (T-OF)
1 2013-09-06 Description of revised process image. FO signals added. Command STOP added. Enable
signals and ESD signal moved. (T-OF)
2 2014-07-07 Added description for firmware download via IrDA interface. Changed pictures of interface board
to current version. Updated descriptions for diagnosis LEDs. (T-OF)
Update Bus connection
3 2016-02-18 Added signal ESD active to process image, starting with FW rev. V2.02.0010. (T-OF)
Contact
DREHMO GmbH
Zum Eichstruck 10
57482 Wenden
Germany
Service
Tel.: [phone]
Fax: [phone]
E-Mail: [e-mail]

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Complementary operating manual
Table of contents
1 Warnings and notes ............................................................................................................... 5
1.1 Standards / directives....................................................................................................... 5
1.2 Commissioning (Electrical connection) ......................................................................... 5
1.3 Maintenance ...................................................................................................................... 5
1.4 Warnings and notes.......................................................................................................... 5
2 Preface................................................................................................................................... 6
2.1 Structure of the interface board ...................................................................................... 6
2.2 Repeater feature ............................................................................................................... 6
2.3 Transmission technique/Physical layer ......................................................................... 7
2.4 Protection functions / Data secure mechanisms.......................................................... 7
3 Electrical connection .............................................................................................................. 8
3.1 Mains connection (Standard) .......................................................................................... 8
3.2 Bus connection (Standard).............................................................................................. 8
3.3 Shield connection.............................................................................................................. 9
3.4 Bus termination ................................................................................................................. 9
3.5 Lightning protection (option)............................................................................................ 9
3.6 Bus cable.......................................................................................................................... 10
4 Jumper / LED’s of the interface board .................................................................................. 11
4.1 Location of the components on the interface board.................................................. 11
4.2 Connectors....................................................................................................................... 12
4.3 Diagnosis LED’s.............................................................................................................. 12
4.3.1 LED RES................................................................................................................... 12
4.3.2 LED DBG .................................................................................................................. 12
4.3.3 LED CAN................................................................................................................... 12
4.3.4 LED CH1................................................................................................................... 13
4.3.5 LED BA1+BA2.......................................................................................................... 13
4.3.6 LED DX1+DX2 ......................................................................................................... 13
4.4 Diagnosis via LCD Display of the actuator ................................................................. 13
5 Communication specific parameters MODBUS RTU ............................................................ 14
5.1 Communication parameters MODBUS RTU .............................................................. 14
5.1.1 Parameter settings using the display ................................................................... 14
5.1.2 Parameter settings using a parameterization tool.............................................. 18
6 MODBUS ............................................................................................................................. 19
6.1 MODBUS protocol layer................................................................................................. 19
6.1.1 Supported function codes....................................................................................... 19
6.1.2 MODBUS addressing model.................................................................................. 19
6.1.3 Valid Offsets/Subfunction codes ........................................................................... 20
6.2 Cyclic data........................................................................................................................ 22
6.2.1 Input register............................................................................................................. 22
6.2.2 Output register ......................................................................................................... 24
6.3 Special function codes ................................................................................................... 26
6.3.1 Read exception-Status (Function code 07)......................................................... 26
6.3.2 Report Slave ID (Function code 17) ..................................................................... 26
7 System functions.................................................................................................................. 27

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Complementary operating manual
7.1 Firmware download ........................................................................................................ 27
7.1.1 Required items......................................................................................................... 27
7.1.2 Step by step description ......................................................................................... 28
7.1.3 Firmwaredownload using IrDA Converter............................................................ 31
8 Appendix .............................................................................................................................. 32
8.1 Reference......................................................................................................................... 32

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Complementary operating manual
1 Warnings and notes
1.1 Standards / directives
DREHMO products are designed and manufactured in compliance with recognized standards and
directives. This is certified in a declaration of incorporation and a declaration of conformity.
The end user or the contractor must ensure that all requirements with respect to assembly,
electrical connection, and commissioning at the place of installation are met.
They include among others:
•Applicable configuration directives for fieldbus applications.
•National regulations, laws, and prescriptions.
1.2 Commissioning (Electrical connection)
During operation of electrical devices it is unavoidable that certain parts carry dangerous voltages.
All personnel working with this device must be familiar with the safety and warning instructions in
this manual and observe the instructions given. Safety instructions and warning signs on the
device must be observed to avoid personal injury or property damage.
1.3 Maintenance
Maintenance directives have to be carefully attended. Otherwise a safe operation of the actuator
or control unit can’t be assured.
1.4 Warnings and notes
Read these instructions carefully before installation and commissioning. Failure to follow them
may lead to personal injury or to material damage.
The following signs draw special attention to safety-relevant procedures in these operation
instructions:
This symbol signifies „additional information“.
Failure to observe may lead to damage occurring.
This symbol signifies „attention“.
Failure to observe may result in damage and personal injury.
This symbol signifies „warning!“
Failure to observe may result in damage and severe personal injury.

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Complementary operating manual
2 Preface
2.1 Structure of the interface board
The MODBUS interface board DiM-17 is equipped with two galvanically separated autonomous
RS485 interfaces. In conjunction with the integrated powerful controller a reapeater functionality is
given. This allows to extend the RS485 communication over larger distances.
In addition the board is equipped with a relay which connects the attached segments in case of a
loss of the repeater functionality to increase the availability.
Controller
DUART
2.2 Repeater feature
The repeater within each interface separates the network into segments. Each connection
between two actuators can therefore be seen as a single point to point connection. The repeater
reconditions the MODBUS signal with a delay of 0.5 tBit.

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Complementary operating manual
2.3 Transmission technique/Physical layer
Data is transmitted by means of a physical connection over a twisted pair two wire cable. The
interface board supports transmission rates up to 115200 Baud.
Bus access is handled in master/slave mode. Only one master can be active at a time (Mono
master mode). The master acts with polling mode and a request / response cycle.
In one master system theoretically 247 slaves can be addressed.
The used protocol is MODBUS RTU.
2.4 Protection functions / Data secure mechanisms
As protection mechanisms against data violation MODBUS RTU implements a parity check for
each byte and a 16 bit CRC for every MODBUS telegram.
In addition a watchdog within the slaves monitors the correct connection to the master. The
behavior of the actuator as well as the timeout value is parameterizable.
The master should also implement a communication monitoring resulting in a failure signalization
in case of communication loss or malfunction.

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Complementary operating manual
3 Electrical connection
3.1 Mains connection (Standard)
Work on electrical equipment and electrical installation work on actuators must be
carried out by electricians or under supervision by fully qualified engineers, in
accordance with the valid electrical regulations.
Wiring should be carried out according to the enclosed wiring diagram. All control
cables shall be shielded to guarantee the electromagnetic compatibility of the
actuator. The main power cable need not be shielded.
The overcurrent protection of the actuator has to be installed inside the power
network. For rated values, see design data.
Pay special attention to the grounding of the actuator (refer to wiring diagram). Electrical
protection is not obtained until all covers are closed.
3.2 Bus connection (Standard)
Wiring is carried out according to the wiring diagram supplied with the actuator. The locations of
the connection terminals are shown in the following picture:
channel 1
shield
channel 1
shield
channel 2
channel
2
diagnosis
channel 1
diagnosis
channel 2

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Complementary operating manual
Connection data:
Strip length: 9 mm
Wire insertion angle relative to PCB: 45°
Connection technology: Phoenix Contact PTSA 1,5/ 2-3,5-Z
Cross section (solid-conductor): 0.5 to 1.5 mm²
Cross section (multi-conductor): 0.5 to 1.5 mm²
Cross section (multi-conductor): 0.5 to 1 mm² (ferrule without plastic shroud)
Pay attention to the ESD protection of the bus circuit board. Especially good personal
earthing is required.
If the bus circuit board is disassembled from its housing transport and storage must
meet ESD requirements.
3.3 Shield connection
The strain-reliefs in front of the terminal connections for the fieldbus can be used to connect the
cable shields to ground instead of the preferred usage of EMC cable glands.
3.4 Bus termination
RS485 networks have to be terminated at the beginning and the end of a segment, to avoid
reflections on the line and for a conditioning of the signals. The termination is automatically
controlled by the loop redundant interface itself depending on the communication state. Therefore
a separate switch for controlling the terminators is obsolete.
3.5 Lightning protection (option)
The connection board can be equipped with dedicated components for lightning protection as an
option.

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Complementary operating manual
3.6 Bus cable
Only cables according to the specification for RS-485 (MODBUS RTU) should be used: 1
Impedance 135 to 165 Ohm, at a test frequency of 3 to 20 MHz
Line capacity < 30 pF per meter
Wire diameter > 0,64 mm
Wire gauge > 0,34 mm² (equivalent AWG 22), max. 1,5 mm²
Loop impedance < 110 Ohm per km
Shielding Copper mesh screen or mesh screen with foil screen
Respect a distance of minimum 20 cm between the bus cable and other cables. If possible, bus
cables should be laid in a separate, conductive, and earthed cable tray.
Make sure to avoid potential differences between the individual devices on the bus (perform a
potential equalization).
There is not standardized color marking for RS485 wiring.
Usually the marking is a follows: P/B = brown and N/A = white
The maximum values at a given transmission rate in conjunction with the above given cable
parameters are as follows:
Bit
rate [kbit/s]
Bit time
Max.
s
egment
leng
t
h
[m]
Max.
stub length
[m]
300 3.3 ms 1200 500
600 1.7 ms 1200 500
1200 833.3 µs 1200 500
2400 416.7 µs 1200 500
4800 208.3 µs 1200 500
9600 104 µs 1200 500
19200 52 µs 1200 500
38400 26 µs 1200 100
57600 17.36 µs 1200 100
115200 8,68 µs 1000 33
1See reference: ‚Modbus over serial line’