Danfoss MCA 122 Modbus TCP User manual

MAKING MODERN LIVING POSSIBLE
Operating Instructions
MCA 122 Modbus TCP

Safety
Safety
Copyright, Limitation of Liability and
Revision Rights
This publication contains information proprietary to
Danfoss. By accepting and using this manual the user
agrees that the information contained herein is used solely
for operating equipment from Danfoss or equipment from
other vendors if such equipment is intended for communi-
cation with Danfoss equipment over an Ethernet serial
communication link. This publication is protected under
the Copyright laws of Denmark and most other countries.
Danfoss does not guarantee that a software program
produced according to the guidelines provided in this
manual functions properly in every physical, hardware, or
software environment.
Although Danfoss has tested and reviewed the documen-
tation within this manual, Danfoss makes no warranty or
representation, either express or implied, with respect to
this documentation, including its quality, performance, or
fitness for a particular purpose.
In no event shall Danfoss be liable for direct, indirect,
special, incidental, or consequential damages arising out of
the use, or the inability to use information contained in
this manual, even if advised of the possibility of such
damages. In particular, Danfoss is not responsible for any
costs including but not limited to the damages incurred as
a result of lost profits or revenue, loss or damage of
equipment, loss of computer programs, loss of data, the
costs to substitute these, or any claims by third parties.
Danfoss reserves the right to revise this publication at any
time and change its contents without prior notice or any
obligation to notify previous users of such revisions or
changes.
Safety Note
WARNING
HIGH VOLTAGE
The voltage of the frequency converter is dangerous
whenever connected to mains. Incorrect installation of the
motor, frequency converter, or fieldbus may damage the
equipment, cause serious personal injury, or death.
Consequently, the instructions in this manual, as well as
national and local rules and safety regulations, must be
complied with.
Safety Regulations
1. The frequency converter must be disconnected
from mains before carrying out repair work.
Check that the mains supply has been discon-
nected and that the necessary time has passed
before removing motor and mains plugs.
2. The off-command on the serial bus does not
disconnect the equipment from mains and should
not be used as a safety switch.
3. Correct protective earthing or grounding of the
equipment must be established. The user must
be protected against supply voltage, and the
motor must be protected against overload in
accordance with applicable national and local
regulations.
4. The earth leakage currents are higher than 3.5
mA.
5. Do not remove the plugs for the motor and
mains supply while the frequency converter is
connected to mains. Check that the mains supply
has been disconnected and that the necessary
time has passed before removing motor and
mains plugs.
Safety MCA 122 Modbus TCP
MG90P202 - VLT®is a protected Danfoss trademark

Warning against Uninteded Start
1. The motor can be brought to a stop with bus
commands while the frequency converter is
connected to mains. These stop functions do NOT
provide protection against unintended starts.
2. While parameters are being changed, there is a
risk that motor starts.
3. Electronic faults in the frequency converter and
cease of
•temporary overload
•faults in supply mains, or
•fault in the motor connection
can cause an unintended start.
WARNING
ELECTRICAL HAZARD
Touching the electrical parts may be fatal - even after the
equipment has been disconnected from mains.
Safety MCA 122 Modbus TCP
MG90P202 - VLT®is a protected Danfoss trademark

Contents
1 Introduction 3
1.1 Introduction 3
1.1.1 About this Manual 3
1.1.2 Assumptions 3
1.1.3 Background Knowledge 3
1.1.4 Available Literature 3
1.1.5 Modbus Conformance 3
1.1.6 Abbreviations 4
2 How to Install 5
2.1 The Modbus TCP Option 5
2.1.1 How to Install Option in Frequency Converter 5
2.1.2 LED Behaviour 6
2.1.3 Topology 7
2.1.4 Network 8
2.1.5 Recommended Design Rules 8
2.1.6 EMC Precautions 10
3 How to Configure 11
3.1 IP Settings 11
3.2 Ethernet Link Parameters 11
3.3 Configuring the Scanner 12
3.4 IP Traffic 15
4 How to Control 17
4.1 How to Control the Frequency Converter 17
4.1.1 Function Codes Supported by Modbus TCP 17
4.2 Modbus TCP Message Framing Structure 17
4.2.1 Function Code 17
4.2.2 Data Field 17
4.2.3 Parameter Handling 17
4.2.4 Storage of Data 17
4.2.5 IND 18
4.2.6 Text Blocks 18
4.2.7 Conversion Factor 18
4.2.8 Parameter Values 18
4.2.9 Modbus Exception Codes 18
4.3 PROFIdrive Control Profile 19
4.3.1 Control Word according to PROFIdrive Profile (CTW) 19
4.3.2 Status Word according to PROFIdrive Profile (STW) 20
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4.3.3 PROFIdrive State - Transition Diagram 21
4.4 Danfoss FC Control Profile 23
4.4.1 Status Word according to Frequency Converter Profile (STW) 24
4.5 Reference Handling 25
4.5.1 Bus Speed Reference Value 25
5 Parameters 27
5.1 Parameter Group 8-** 27
5.2 Parameter Group 12-** 30
5.2.1 12-0* IP Settings 30
5.2.2 12-1* Ethernet Link Parameters 31
5.2.3 12-2* Process Data 32
5.2.4 Modbus TCP 32
5.2.5 12-8* Other Ethernet Services 33
5.2.6 12-9* Advanced Ethernet Settings 33
5.3 Parameter List 34
5.4 Data Types 36
5.4.1 Data Types Supported by FC 102/FC 202/FC 302 36
6 Troubleshooting 37
6.1 Step-by-step Troubleshooting 37
6.2 Alarm Word and Warning Word 37
Index 41
Contents MCA 122 Modbus TCP
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1 Introduction
1.1 Introduction
1.1.1 About this Manual
First time users can find the most essential information for
quick installation and set-up in these chapters:
1 Introduction
2 How to Install
3 How to Configure
For more detailed information including the full range of
set-up options and diagnosis tools, refer to the chapters:
3 How to Configure
4 How to Control
5 Parameters
6 Troubleshooting
Terminology
Ethernet is a common term used to describe the physical
layer of the network and does not relate to the application
protocol.
1.1.2 Assumptions
These operating instructions are under the conditions that
the MCA 122 Modbus TCP option is used with a Danfoss
FC 100/FC 202/FC 300 frequency converter, and that the
installed option supports the interfaces described in this
document and that all the requirements stipulated in the
option, as well as the frequency converter, are strictly
observed along with all limitations herein.
1.1.3 Background Knowledge
The Danfoss Modbus Option Card is designed to
communicate with any system complying with the Modbus
Messaging on TCP/IP Implementation Guide V1.0b and
Modbus Application Protocol Specification V1.1b standard.
Familiarity with this technology is assumed. Issues
regarding hardware or software produced by other
manufacturers, including commissioning tools, are beyond
the scope of this manual, and are not the responsibility of
Danfoss.
For information regarding commissioning tools, or
communication to a non-Danfoss node, consult the
appropriate manuals.
1.1.4 Available Literature
Available Literature for FC 102/FC 202/FC 300
-The Operating Instructions for VLT
®
HVAC Drive FC
102, VLT
®
AQUA Drive FC 202 and VLT
®
AutomationDrive FC 302 provide the necessary
information for getting the frequency converter
up and running.
-The Design Guides for VLT
®
HVAC Drive FC 102,
VLT
®
AQUA Drive FC 202 and VLT
®
AutomationDrive FC 302 entail all technical
information about the frequency converter design
and applications including encoder, resolver, and
relay options.
-The VLT
®
AutomationDriveFC 302 Profibus
Operating Instructions, provide the information
required for controlling, monitoring, and
programming the frequency converter via a
Profibus Fieldbus.
-The VLT
®
AutomationDriveFC 302 Operating
Instructions, provide the information required for
controlling, monitoring, and programming the
frequency converter via a DeviceNet Fieldbus.
-The MCT 10 Set-up Software Operating Instructions,
provide information for installation and use of the
software on a PC.
-The VLT
®
AutomationDriveFC 302 IP21/Type 1
Instruction, provides information for installing the
IP21/Type 1 option.
-The VLT
®
AutomationDriveFC 302 24 V DC Backup
Instruction, provides information for installing the
24 V DC Backup option.
Danfoss technical literature is also available online at
www.danfoss.com/BusinessAreas/DrivesSolutions/
Documentations/Technical+Documentation.htm.
1.1.5 Modbus Conformance
The Modbus option is tested to conform to the Modbus
standards and is certified towards conformance test level
version 3.
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1.1.6 Abbreviations
Abbreviation Definition
API Actual Packet Interval
CC Control Card
CIP Common Industrial Protocol
CTW Control Word
DHCP Dynamic Host Configuration Protocol
EMC Electromagnetic Compatibility
I/O Input/Output
IP Internet Protocol
LCP Local Control Panel
LED Light Emitting Diode
LSB Least Significant Bit
MAR Major Recoverable fail
MAU Major Unrecoverable fail
MAV Main Actual Value (actual output)
MSB Most Significant Bit
MRV Main Reference Value
N/A Not applicable
ODVA Open DeviceNet Vendor Association
PC Personal Computer
PLC Programmable Logic Controller
PNU Parameter Number
REF Reference (=MRV)
RTC Real Time Clock
s Second
STP Spanning tree Protocol
STW Status Word
Table 1.1 Abbreviations
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2 How to Install
2.1 The Modbus TCP Option
Ethernet Port 1 Ethernet Port 2
MS LED
NS LEDs
MCA122
MODBUS TCP
SW. ver. TM. ver.
MS
NS1
NS2
Ethernet Port 1 Ethernet Port2
Option A
130B1196
MAC 00-1B-08-00-00-00
Address
8 7 6 543 2 1
ON
OFF
130BD190.10
Illustration 2.1 Overview of the Option
2.1.1 How to Install Option in Frequency
Converter
Items required for installing a fieldbus option in the
frequency converter
•The fieldbus option
•Fieldbus option adapter frame for the FC 102/FC
202/FC 300. This frame is deeper than the
standard frame, to allow space for the fieldbus
option beneath
•Strain relief (only for A1 and A2 enclosures)
Illustration 2.2 Option Installed in Frequency Converter
Illustration 2.3 Strain Relief for Enclosure Types A1 and A2
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Instructions
1. Remove LCP panel from the frequency converter.
2. Remove the frame located beneath and discard it.
3. Push the option into place. The Ethernet
connectors must be facing upwards.
4. Remove both knock-outs on the fieldbus option
adapter frame.
5. Push the fieldbus option adapter frame for the
frequency converter into place.
6. Replace the LCP and attach cable.
NOTICE
Do not strip the Ethernet cable and ground it via the strain
relief-plate! The grounding of screened Ethernet cable is
done through the RJ-45 connector on the option.
NOTICE
After installing the MCA 122 option, be aware of the
following parameter settings:
8-01 Control Site: [2] control word only or [0] Digital and ctrl.
word
8-02 Control Word Source: [3] Option A
2.1.2 LED Behaviour
The option has three bi-coloured LEDs
LED label Description
MS Module Status
NS1 Network Status Ethernet Port 1
NS2 Network Status Ethernet Port 2
Table 2.1 Description of LEDs
State LED Description
No power Off The device is un-powered
Device operational Green: Solid green The device is operational
Standby Green: Flashing green The device needs commissioning
Minor fault Red: Flashing red The device has detected a recoverable fault
Major fault Red: Solid red The device has detected an un-recoverable
fault
Self test Red: Flashing red/
green The Modbus TCP option is in self-test mode
Green:
No IP address Yellow Steady yellow No IP address configured or obtained
Wink Yellow Flashing yellow Flash for 20 s
Table 2.2 MS: Module Status
State LED Description
No IP-address (no
power) Off No link present (or is un-powered)
Connected Green: Solid green Link present; but nor winked and no ACD
Duplicate IP Red: Solid red The IP-address assigned to the device is
already in use
Self test Red: Flashing red/
green The Modbus TCP is in self-test mode
Green
Device has been winked Yellow Flashing yellow Flash for 20 s
Link present at 10 Mbps Yellow Steady yellow Link present; but nor winked and no ACD
Table 2.3 NS1+NS2: Network Status (One per Port)
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2.1.3 Topology
The MCA 122 features a built-in Ethernet-switch, thus having two Ethernet RJ-45 connectors. This enables the possibility for
connecting several Modbus TCP options in a line topology as an alternative to the typical star-topology.
The two ports are equal, in the sense that they are transparent for the option. If only one connector is used, either port can
be used.
AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
130BA903.10
Illustration 2.4 Star Topology
AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
130BA904.10
Illustration 2.5 Line Topology
NOTICE
For line topology, refer to 2.1.5 Recommended Design Rules. In a line topology all frequency converters must be powered,
either by mains or by their 24 V DC option cards, for the built-in switch to work.
NOTICE
Observe that mounting frequency converters of different power-sizes in a line topology may result in unwanted power-off
behaviour.
Smaller frequency converters discharge faster than bigger frequency converters. This can result in loss of link in the line
topology, which may lead to control word timeout.
To avoid this, mount the frequency converters with the longest discharge time first in the line topology.
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22

AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
AutomationDrive
VLT
½
AutomationDrive
VLT
AutomationDrive
VLT
130BA905.10
Illustration 2.6 Ring/Redundant Line Topology
2.1.4 Network
It is of high importance that the media chosen for Ethernet
data transmission are suitable. Usually CAT 5e and six
cables are recommended for industrial applications. Both
types of cable are available as Unshielded Twisted Pair and
Shielded Twisted Pair. Shielded cables are recommended
for use in industrial environments and with frequency
converters.
A maximum cable-length of 100 m is allowed between
switches.
Optical fibres can be used for gapping longer distances
and providing galvanic isolation.
For connecting Modbus TCP devices both hubs and
switches can be used. It is, however, always recommended
to use suitable industrial graded Ethernet switches. For
more information regarding IP-switching, refer to 3.4.1 IP
Traffic.
2.1.5 Recommended Design Rules
While designing Ethernet networks special attention and
caution must be taken regarding active network
components.
While designing a network for line topology it is important
to notice that a small delay is added with each every
switch in the line.
It is not recommended to connect more than 32 frequency
converters in a line at any API. Exceeding the
recommended design rules, may result in failing communi-
cation.
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2

Illustration 2.7
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2.1.6 EMC Precautions
NOTICE
Relevant national and local regulations, for example
regarding protective earth connection, must be observed.
For interference-free operation of the Ethernet network,
take the following EMC precautions.
•Keep the Ethernet communication cable away
from motor and brake resistor cables to avoid
coupling of high frequency noise from one cable
to another
•Maintain the greatest possible distance (min. 200
mm (8 inches)) between cables. Especially, where
cables run in parallel over long distances.
•If crossing is unavoidable, the Ethernet cable
must cross motor and brake resistor cables at an
angle of 90°
Additional EMC information is available in the frequency
converter Design Guide.
130BC509.10
Illustration 2.8 EMC-correct Installation
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3 How to Configure
3.1 IP Settings
All IP-related parameters are located in parameter group
12-0* IP Settings:
•12-00 IP Address Assignment
•12-01 IP Address
•12-02 Subnet Mask
•12-03 Default Gateway
•12-04 DHCP Server
•12-05 Lease Expires
•12-06 Name Servers
•12-07 Domain Name
•12-08 Host Name
•12-09 Physical Address
The MCA 122 option offers several ways of IP address
assignment.
Setting up the frequency converter with manually assigned
IP address
Parameter Value
12-00 IP Address Assignment [0] MANUAL
12-01 IP Address 192.168.0.xxx*
12-02 Subnet Mask 255.255.255.0*
12-03 Default Gateway optional
Table 3.1 Assigning IP Adresses Manually
*= Class C IP address example. Any valid IP address can be entered.
NOTICE
A power-cycle is necessary after setting the IP parameters
manually.
Setting up the frequency converter with automatically
(BOOTP/DHCP) assigned IP address
Parameter Value
12-00 IP Address
Assignment
[1] DHCP/[2] BOOTP
12-01 IP Address Read only
12-02 Subnet Mask Read only
12-03 Default Gateway Read only
Table 3.2 Assigning IP Adresses Automatically
By IP address assigned by DHCP/BOOTP server, the
assigned IP Address and Subnet Mask can be read out in
12-01 IP Address and 12-02 Subnet Mask. In 12-04 DHCP
Server DHCP Server, the IP address of the found DHCP or
BOOTP server is displayed.
For DHCP only: The remaining lease-time can be read-out
in 12-05 Lease Expires Lease Expires.
12-09 Physical Address, Physical Address reads out the MAC
address of option, which is also printed on the label of the
option. If using fixed leases together with DHCP or BOOTP,
the physical MAC address is linked with a fixed IP address.
NOTICE
If no DHCP or BOOTP reply has been received after four
attempts (for example, if the DHCP/BOOTP server has been
powered off), the option will fallback to the last good
known IP address.
12-03 Default Gateway, Default Gateway is optional and
only used in routed networks.
12-06 Name Servers, Name Servers
12-07 Domain Name, Domain Name
12-08 Host Name, Host Name
are used with Domain Name Server systems and are all
optional. If DHCP or BOOTP is selected as IP address
assignment, these parameters are read only.
NOTICE
It is only possible to assign valid class A, B, and C IP
address to the option. The valid ranges are shown in
Table 3.3.
Class A 1.0.0.1 - 126.255.255.254
Class B 128.1.0.1 - 191.255.255.254
Class C 192.0.1.1 - 223.255.254.254
Table 3.3 Valid Ranges of IP Addresses
3.2 Ethernet Link Parameters
Parameter group 12-1* Ethernet Link Parameters holds
information Ethernet Link information:
•12-10 Link Status
•12-11 Link Duration
•12-12 Auto Negotiation
•12-13 Link Speed
•12-14 Link Duplex
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NOTICE
The Ethernet Link Parameters are unique per port.
12-10 Link Status and 12-11 Link Duration displays
information on the link status, per port.
12-10 Link Status displays Link or No Link according to the
status of the present port.
12-11 Link Duration displays the duration of the link on the
present port. If the link is broken the counter resets.
12-12 Auto Negotiation – is a feature that enables two
connected Ethernet devices to choose common
transmission parameters, such as speed and duplex mode.
In this process, the connected devices first share their
capabilities as for these parameters and then choose the
fastest transmission mode they both support.
By default this function is enabled.
Incapability between the connected devices, may lead to
decreased communication performance.
To prevent this, Auto Negotiation can be disabled.
If 12-12 Auto Negotiation is set to OFF, link speed and
duplex mode can be configured manually in 12-13 Link
Speed and 12-14 Link Duplex.
12-13 Link Speed – displays/sets the link speed per port.
“None” is displayed if no link is present.
12-14 Link Duplex – displays/sets the duplex mode per
port.
Half-duplex provides communication in both directions,
but only in one direction at a time (not simultaneously).
Full-duplex allows communication in both directions, and
unlike half-duplex, allows for communication in both
directions, to happen simultaneously.
3.3 Configuring the Scanner
For configuring the scanner to communicate to the
frequency converter, no system (for example, EDS, GSD file)
file is needed. The frequency converter is handled as a
generic device and as such, configured directly in the
scanner. The following example sets up the scanner to IP
addresses 192.168.1.20 and the FC 302 to address
192.168.1.20.
Configuring a Modicon scanner
The following example uses the Unity Pro tool from Group
Schneider to configure the PLC. The example only shows
the setting up of the Protocol and assigning I/O mapping
to internal memory of the PLC.
Under network, add a network by right clicking the
Network menu and select “New Network”
Illustration 3.1 Adding a Network
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By selecting this menu, assign a name to the new network.
In this example “Danfoss” has been chosen.
Illustration 3.2 Assigning a Network Name
After clicking [OK], the network “Danfoss” should show up
under Networks and by selecting the Network, the main
configuration page is shown.
Illustration 3.3 Main Configuration Page
Menu Menu point Setting
Model Family Model Family NOE 0100, NOE 110
Model Utilities IO Scanning YES
Global Data NO
Address Server NO
IP address configu-
ration
Configured/From a
server
Configured
IP address 192.168.001.020
Subnetwork mask 255.255.255.0
Gateway address 0.0.0.0
Ethernet Configu-
ration
Ethernet Configu-
ration
Ethernet II
Table 3.4 Menu Settings
In the IP Configuration tab, press the [Configured] key, and the IP
address and fill out [Subnetwork mask]. In this example the address
192.168.1.20 is used as the address for the master.
The step assigns the protocol to the scanner, which is done
by selecting the scanner and selecting the “Function” menu
and enables the Ethernet by selecting “ETH TCP IP” This brings
up the Net Link menu, where “Danfoss” has to be selected. At
this time, the “Danfoss” Protocol is assigned to the Scanner
and the last step is to configure the scanner to read and write
holding registers of the FC 302.
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Illustration 3.4 Net Link Menu
Menu Menu point Setting
Function Function ETH TCP IP
Net Link Net Link Danfoss
Table 3.5 Menu Settings
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At this time the “Danfoss” Protocol is assigned to the Scanner and the last step is to configure the scanner to read and
write holding registers of the FC 302.
By first selecting the Danfoss network and second, selecting the IO Scanning tab, the scanning list appears. Fill out the list
as shown in Illustration 3.5.
130BB261.11
Illustration 3.5 Scanning List
Menu Menu point Setting
IO Scanning IP address 192.168.001.030
Unit ID 255
Health Timeout 1500
Repetitive rate 60
RD Master Object %MW100
RD Slave Index 2910
RD Length 10
Last Value Hold Last
VR Master Object %MW200
VR Slave Index 2810
VR Lenght 10
Description -
Table 3.6 Menu Settings
This configuration copies the information stored from
%MW200 to %M209 in the PLC to the Holding register
2810 to 2819 of the FC 302. It reads the holding registers
2910 to 2919 of the FC 302 to the PLCs memory %MW100
to %M109.
3.4 IP Traffic
The use of Ethernet-based network for industrial
automation purposes, calls for careful and thorough
network design. Especially the use of active network
components like switches and routers requires detailed
know-how about the behaviour of IP traffic.
Some important issues
IGMP
IGMP (Internet Group Management Protocol) is an
integrated part of IP. It allows hosts to join or leave a
multicast host group. Group membership information is
exchanged between a specific host and the nearest
multicast router.
Spanning Tree Protocol (STP)
For an Ethernet network to function properly, only one
active path can exist between two nodes. Spanning-Tree
Protocol is a link management protocol that provides path
redundancy while preventing undesirable loops in the
network.
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When loops occur, some switches see stations appearing
on both sides of them. This condition confuses the
forwarding algorithm and allows for duplicate frames to be
forwarded.
To provide path redundancy, Spanning-Tree Protocol
defines a tree that spans all switches in an extended
network. Spanning-Tree Protocol forces certain redundant
data paths into a standby (blocked) state. If one network
segment in the Spanning-Tree Protocol becomes
unreachable, or if Spanning-Tree Protocol costs change,
the spanning-tree algorithm reconfigures the spanning-tree
topology and reestablishes the link by activating the
standby path.
Spanning-Tree Protocol operation is necessary if the
frequency converters are running in a ring/redundant line
topology.
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