Danfoss VLT Soft Starter MCD600 Modbus RTU Card
Safety
Disclaimer
The examples and diagrams in this manual are included solely for illustrative purposes. The information contained in this manual is subject to change at any time and without prior notice. Responsibility or liability is never accepted for direct, indirect, or consequential damage resulting from the use or application of this equipment.
Warnings SHOCK HAZARD
Attaching or removing accessories while the soft starter is connected to mains voltage may cause personal injury.
Before attaching or removing accessories, isolate the soft starter from mains voltage.
WARNING RISK OF PERSONAL INJURY AND EQUIPMENT DAMAGE
Inserting foreign objects or touching the inside of the soft starter while the expansion port cover is open may endanger personnel and can damage the soft starter.
Do not insert foreign objects in the soft starter with the port cover open.
Do not touch the inside of the soft starter with the port cover open.
Important User Information
Observe all necessary safety precautions when controlling the soft starter remotely. Alert personnel that machinery may start without warning.
The installer is responsible for following all instructions in this manual and for following correct electrical practice.
Use all internationally recognized standard practice for RS485 communication when installing and using this equipment.
Introduction
Compatibility
This communication expansion card is suitable for use with VLT® Soft Starter MCD 600. The card is available in 2 versions:
175G0127: VLT® Soft Starter MCD 600 Modbus RTU Card
175G0027: VLT® Soft Starter MCD 600 Modbus RTU Card with Ground Fault Protection.
This manual is suitable for use with both versions.
This Installation Guide is intended for use with version 2.x of the VLT® Soft Starter MCD 600 Modbus RTU Card. Version 1.x of the Modbus RTU Card does not support custom users, TCP connection, or IoT operation.
Installation
Installing the Expansion Card Procedure
Push a small flat-bladed screwdriver into the slot in the center of the expansion port cover and ease the cover away from the soft starter.
- Line up the card with the expansion port.
- Gently push the card along the guide rails until it clicks into the soft starter.
Example
Connecting to the Network
The expansion card must be installed in the soft starter.
Procedure
- Restore control power.
- Connect field wiring via the 5-way connector plug.
Example
| Pin | Function |
| 1, 2 | Data A |
| 3 | Common |
| 4, 5 | Data B |
Operation
Prerequisites
The Modbus RTU Card must be controlled by a Modbus client (such as a PLC) which complies with the Modbus Protocol Specification.
For successful operation, the client must also support all functions and interfaces described in this manual.
Client Configuration
For standard Modbus 11-bit transmission, configure the client for 2 stop bits with no parity and 1 stop bit for odd or even parity.
For 10-bit transmission, configure the client for 1 stop bit.
In all cases, the client baud rate and server address must match those set in parameters 12-1 to 12-4.
The data polling interval must be long enough for the module to respond. Short polling intervals may cause inconsistent or incorrect behavior, particularly when reading multiple registers. The recommended minimum polling interval is 300 ms.
Configuration
Modbus Network Settings
Set the network communication parameters for the card via the soft starter. For details on how to configure the soft starter, see the VLT® Soft Starter MCD 600 Operating Guide.
Table 1: Parameter Settings
| Parameter | Parameter name | Description |
| 12-1 | Modbus Address | Sets the Modbus RTU network address for the soft starter. |
| 12-2 | Modbus Baud Rate | Selects the baud rate for Modbus RTU communications. |
| 12-3 | Modbus Parity | Selects the parity for Modbus RTU communications. |
| 12-4 | Modbus Timeout | Selects the timeout for Modbus RTU communications. |
Enabling Network Control
The soft starter only accepts commands from the expansion card if parameter 1-1 Command Source is set to Network.
NOTICE If the reset input is active, the soft starter does not operate. If a reset switch is not required, fit a link across terminals RESET, COM+ on the soft starter.
Feedback LEDs
| LED status | Description |
| Off | The soft starter is not powered up. |
| On | Communication active. |
| Flashing | Communication inactive. |
NOTICE If communication is inactive, the soft starter may trip on Network Communications. If parameter 6-13 Network Communications is set to Soft Trip and Log or Trip Starter, the soft starter requires a reset.
Modbus Registers
PLC Configuration
Use the tables in 5.5 Standard Mode to map registers within the device to addresses within the PLC.
NOTICE All references to registers mean the registers within the device unless otherwise stated.
Compatibility
The Modbus RTU Card supports 2 modes of operation:
In Standard Mode, the device uses registers defined in the Modbus Protocol Specification.
In Legacy Mode, the device uses the same registers as the clip-on Modbus Module supplied by Danfoss for use with older soft starters. Some registers differ from those specified in the Modbus Protocol Specification.
Ensuring Safe and Successful Control
Data written to the device remains in its registers until the data is overwritten or the device is reinitialized.
If the soft starter should be controlled via parameter 7-1 Command Override or should be disabled via the reset input (terminals RESET, COM+), fieldbus commands should be cleared from the registers. If a command is not cleared, it is resent to the soft starter
once fieldbus control resumes.
Parameter Management
Parameters can be read from and written to the soft starter. The Modbus RTU Card can read or write a maximum of 125 registers in 1 operation.
NOTICE The total number of parameters in the soft starter may vary according to the model and parameter list of the soft starter. Attempting to write to a register not associated with a parameter returns an error code 02 (illegal data address). Read register 30602 to determine the total number of parameters in the soft starter.
NOTICE Do not change the default values of the Advanced parameters (parameter group 20-** Advanced Parameters). Changing these values may cause unpredictable behavior in the soft starter.
Standard Mode
Command and Configuration Registers (Read/Write)
Table 2: Description of Read/Write Registers
| Register | Description | Bits | Details |
| 40001 | Command (single write) | 0–7 | To send a command to the starter, write the required value: 00000000 = Stop 00000001 = Start 00000010 = Reset 00000100 = Quick stop (coast to stop) 00001000 = Forced communication trip 00010000 = Start using Parameter Set 1 00100000 = Start using Parameter Set 2 01000000 = Reserved |
| Register | Description | Bits | Details |
| 10000000 = Reserved | |||
| 8–14 | Reserved | ||
| 15 | Must = 1 | ||
| 40002 | Reserved | ||
| 40003 | Reserved | ||
| 40004 | Reserved | ||
| 40005 | Reserved | ||
| 40006 | Reserved | ||
| 40007 | Reserved | ||
| 40008 | Reserved | ||
| 40009–40xxx | Parameter management (single or multiple read/ write) | 0–15 | Manage soft starter programmable parameters. See the VLT® Soft Start- er MCD 600 Operating Guide for a complete parameter list. |
Status Reporting Registers (Read Only)
NOTICE For models MCD6-0063B and smaller (soft starter model ID 1~4), the current and frequency reported via communications registers are 10 times greater than the actual value.
Table 3: Description of Read Registers
| Register | Description | Bits | Details |
| 30003 | Reserved | ||
| 30004 | Reserved | ||
| 30005 | Reserved | ||
| 30006 | Reserved | ||
| 30007 | Reserved | ||
| 30008 | Reserved | ||
| 30600 | Version | 0–5 | Binary protocol version |
| 6–8 | Parameter list major version | ||
| 9–15 | Product type code: 15 = MCD 600 | ||
| 30601 | Model number | 0–7 | Reserved |
| 8–15 | Soft starter model ID | ||
| 30602 | Changed parameter number | 0–7 | 0 = No parameters have changed 1–255 = Index number of the last parameter changed |
| 8–15 | Total number of parameters available in the soft starter |
| Register | Description | Bits | Details |
| 30603 | Changed parameter value | 0–15 | Value of the last parameter that was changed, as indicated in register 30602 |
| 30604 | Starter state | 0–4 | 0 = Reserved 1 = Ready 2 = Starting 3 = Running 4 = Stopping 5 = Not ready (restart delay, restart temperature check, run simulation, reset input is open) 6 = Tripped 7 = Programming mode 8 = Jog forward 9 = Jog reverse |
| 5 | 1 = Warning | ||
| 6 | 0 = Uninitialized 1 = Initialized | ||
| 7 | Command source 0 = Remote LCP, Digital Input, Clock 1 = Network | ||
| 8 | 0 = Parameters have changed since last parameter read 1 = No parameters have changed | ||
| 9 | 0 = Negative phase sequence 1 = Positive phase sequence | ||
| 10–15 | Reserved | ||
| 30605 | Current | 0–13 | Average rms current across all 3 phases |
| 14–15 | Reserved | ||
| 30606 | Current | 0–9 | Current (% motor FLC) |
| 10–15 | Reserved | ||
| 30607 | Motor temperature | 0–7 | Motor thermal model (%) |
| 8–15 | Reserved | ||
| 30608 | Power | 0–11 | Power |
| 12–13 | Power scale 0 = Multiply power by 10 to get W 1 = Multiply power by 100 to get W 2 = Power (kW) 3 = Multiply power by 10 to get kW | ||
| 14–15 | Reserved | ||
| 30609 | % Power factor | 0–7 | 100% = power factor of 1 |
| Register | Description | Bits | Details |
| 8–15 | Reserved | ||
| 30610 | Voltage | 0–13 | Average rms voltage across all 3 phases |
| 14–15 | Reserved | ||
| 30611 | Current | 0–13 | Phase 1 current (rms) |
| 14–15 | Reserved | ||
| 30612 | Current | 0–13 | Phase 2 current (rms) |
| 14–15 | Reserved | ||
| 30613 | Current | 0–13 | Phase 3 current (rms) |
| 14–15 | Reserved | ||
| 30614 | Voltage | 0–13 | Phase 1 voltage |
| 14–15 | Reserved | ||
| 30615 | Voltage | 0–13 | Phase 2 voltage |
| 14–15 | Reserved | ||
| 30616 | Voltage | 0–13 | Phase 3 voltage |
| 14–15 | Reserved | ||
| 30617 | Parameter list version number | 0–7 | Parameter list minor revision |
| 8–15 | Parameter list major version | ||
| 30618 | Digital input state | 0–15 | For all inputs, 0 = open, 1 = closed (shorted) 0 = Start/Stop 1 = Reserved 2 = Reset 3 = Input A 4 = Input B 5 to 15 = Reserved |
| 30619 | Trip code | 0–15 | See 5.7 Trip Codes |
| 8–15 | Reserved | ||
| 30620 | Reserved | ||
| 30621 | Frequency | 0–15 | Frequency (Hz) |
| 30622 | Ground current | 0–15 | Ground Current (A) |
| 30623~30631 | Reserved |
NOTICE Reading register 30603 (Changed parameter value) resets registers 30602 (Changed parameter number) and 30604 (Parameters have changed). Always read registers 30602 and 30604 before reading register 30603.
Examples
Table 4: Command: Start
| Message | Soft starter address | Function code | Register address | Data | CRC |
| In | 20 | 06 | 40002 | 1 | CRC1, CRC2 |
| Out | 20 | 06 | 40002 | 1 | CRC1, CRC2 |
Table 5: Soft Starter State: Running
| Message | Soft starter address | Function code | Register address | Data | CRC |
| In | 20 | 03 | 40003 | 1 | CRC1, CRC2 |
| Out | 20 | 03 | 2 | xxxx0011 | CRC1, CRC2 |
Table 6: Trip Code: Motor Overload
| Message | Soft starter address | Function code | Register address | Data | CRC |
| In | 20 | 03 | 40004 | 1 | CRC1, CRC2 |
| Out | 20 | 03 | 2 | 00000010 | CRC1, CRC2 |
Table 7: Download Parameter from Soft Starter – Read Parameter 5 (Parameter 1-5 Locked Rotor Current), 600%
| Message | Soft starter address | Function code | Register | Data | CRC |
| In | 20 | 03 | 40013 | 1 | CRC1, CRC2 |
| Out | 20 | 03 | 2 (bytes) | 600 | CRC1, CRC2 |
Table 8: Upload Single Parameter to Soft Starter – Write Parameter 61 (Parameter 2-9 Stop Mode), set =1
| Message | Soft starter address | Function code | Register | Data | CRC |
| In | 20 | 06 | 40024 | 1 | CRC1, CRC2 |
| Out | 20 | 06 | 40024 | 1 | CRC1, CRC2 |
Table 9: Upload Multiple Parameters to Soft Starter – Write Parameters 9, 10, 11 (Parameters 2-2 to 2-4) Set to Values of 15 s, 300%, and 350%, Respectively
| Message | Soft starter address | Function code | Register | Data | CRC |
| In | 20 | 16 | 40017, 3 | 15, 300, 350 | CRC1, CRC2 |
| Out | 20 | 16 | 40017, 3 | 15, 300, 350 | CRC1, CRC2 |
Trip Codes
| Code | Description |
| 0 | No trip |
| 1 | Excess start time |
| Code | Description |
| 2 | Motor overload |
| 3 | Motor thermistor |
| 4 | Current imbalance |
| 5 | Frequency |
| 6 | Phase sequence |
| 7 | Instantaneous overcurrent |
| 8 | Power loss |
| 9 | Undercurrent |
| 10 | Heatsink overtemperature |
| 11 | Motor connection |
| 12 | Input A trip |
| 13 | FLC too high |
| 14 | Unsupported option (function not available in inside delta) |
| 15 | Communications card fault |
| 16 | Forced network trip |
| 17 | Internal fault |
| 18 | Overvoltage |
| 19 | Undervoltage |
| 23 | Parameter out of range |
| 24 | Input B trip |
| 26 | L1 phase loss |
| 27 | L2 phase loss |
| 28 | L3 phase loss |
| 29 | L1-T1 shorted |
| 30 | L2-T2 shorted |
| 31 | L3-T3 shorted |
| 33 | Time-overcurrent (bypass overload) |
| 34 | SCR overtemperature |
| 35 | Battery/clock |
| 36 | Thermistor circuit |
| 47 | Overpower |
| 48 | Underpower |
| Code | Description |
| 56 | LCP disconnected |
| 57 | Zero speed detect |
| 58 | SCR itsm |
| 59 | Instantaneous overcurrent |
| 60 | Rating capacity |
| 70 | Current read err L1 |
| 71 | Current read err L2 |
| 72 | Current read err L3 |
| 73 | Remove mains volts (mains voltage connected in run simulation) |
| 74 | Motor connection T1 |
| 75 | Motor connection T2 |
| 76 | Motor connection T3 |
| 77 | Firing fail P1 |
| 78 | Firing fail P2 |
| 79 | Firing fail P3 |
| 80 | VZC fail P1 |
| 81 | VZC fail P2 |
| 82 | VZC fail P3 |
| 83 | Low control volts |
| 84–96 | Internal fault x. Contact the local supplier with the fault code (x). |
Modbus Error Codes
| Code | Description | Example |
| 1 | Illegal function code | The adapter or soft starter does not support the requested function. |
| 2 | Illegal data address | The adapter or soft starter does not support the specified register address. |
| 3 | Illegal data value | The adapter or soft starter does not support 1 of the received data values. |
| 4 | Slave device error | An error occurred while trying to perform the requested function. |
| 6 | Slave device busy | The adapter is busy (for example writing parameters to the soft starter). |
Ground Fault Protection
Overview
NOTICE Ground fault protection is only available on ground fault enabled option cards with soft starters running a compatible version of software. Contact the supplier for assistance.
The Modbus RTU Card can detect ground current and trip before the equipment is damaged.
Ground fault protection requires a 1000:1 or 2000:1 current transformer (not supplied). The CT should be rated 1 VA or 5 VA. The soft starter can be configured to trip at 1–50 A. If ground fault current rises above 50 A, the soft starter trips immediately.
Parameter 40-3 Ground Fault Trip Active selects when ground fault protection is active.
Connect the CT to the Ground Fault Inputs
To use ground fault protection, a common-mode current transformer (CT) must be installed around all 3 phases.
Procedure
Use a 1000:1 or 2000:1 CT with a rating of 1 VA or 5 VA.
Set parameter 40-5 Ground Fault CT ratio to match the CT.
Connect the CT to the ground fault terminals (G1, G2, G3).
For maximum protection, the CT should be installed on the input side of the soft starter.
Configure Ground Fault Protection Settings
Ground fault protection settings must be set in the soft starter.
| Parameter | Description |
| Parameter 40-1 Ground Fault Level | Sets the trip point for ground fault protection. |
| Parameter 40-2 Ground Fault Delay | Shows the response of the Modbus RTU Card to ground fault variation, avoiding trips due to momentary fluctuations. |
| Parameter 40-3 Ground Fault Trip Active | Selects when a ground fault trip can occur. |
| Parameter 40-4 Ground Fault Action | Selects the response of the soft starter to the protection event. |
| Parameter 40-5 Ground Fault CT Ratio | Set to match the ratio of the ground current measuring CT. |
Specifications
Connections
- Soft starter 6-way pin assembly
- Network 5-way male and unpluggable female connector (supplied)
- Maximum cable size 2.5 mm2 (14 AWG)
Settings
- Protocol Modbus RTU, AP ASCII
- Address range 0–254
- Data rate (bps) 4800, 9600, 19200, 38400
- Parity None, Odd, Even, 10-bit
- Timeout None (Off), 10 s, 60 s, 100 s
Certification
- RCM IEC 60947-4-2
- CE EN 60947-4-2
- RoHS Compliant with EU Directive 2011/65/EU
Danfoss A/S
Ulsnaes 1
DK-6300 Graasten
vlt-drives.danfoss.com
Danfoss can accept no responsibility for possible errors in catalogs, brochures, and other printed material. Danfoss reserves the right to alter its products without notice. This also applies to products already on order provided that such alterations can be made without subsequential changes being necessary in specifications already agreed. All trademarks in this material are property of the respective companies. Danfoss and the Danfoss logotype are trademarks of Danfoss A/S. All rights reserved.
Documents / Resources
 | Danfoss VLT Soft Starter MCD600 Modbus RTU Card [pdf] Installation Guide VLT Soft Starter MCD600 Modbus RTU Card, VLT Soft Starter MCD600, Modbus RTU Card, RTU Card, Card |