The VLT® Multiaxis Servo Drive MSD 520 system is a generic central servo solution and the fundamental part of the VLT® FlexMotion™ concept.
Its flexibility and modularity in hardware and software gives the freedom to design or engineer machines according to the application needs.
The MSD 520 comprises these modules:
- VLT® Power Supply Module PSM 520 with Decentral Access Module (DAM) factory option
- VLT®Servo Drive Module SDM 521 for single axis and SDM 522 for double axis
- VLT® Expansion Module EXM 520
To optimize the space requirements, some modules are available in two enclosure sizes, either 50 mm or 100 mm wide.
Fast and fail-safe installation
Enjoy easy mounting and failsafe installation thanks to a unique Click and Lock concept where DC-link and control voltage supply are integrated in the backplate of each module. Depending on the machine architecture, you can use the MSD 520 as a standalone central concept or in a mixed system together with the VLT® Integrated Servo Drive ISD® 520 and VLT® Decentral Servo Drive DSD 520. Extensions or adjustments to the machine are easy to implement - just add or swap modules accordingly.
Choose your preferred protocol
Open connectivity to common real-time Ethernet systems, such as EtherCAT, POWERLINK and PROFINET, and IEC 61131-3-based programming and PLCopen certified Motion libraries makes the system even more flexible and easy to integrate into various engineering environments.
Modules of the MSD 520
VLT® Power Supply Module PSM 520
The PSM 520 generates a 565-680 DC-link voltage and is available in 3 ratings: 10, 20 or 30 kW and 200% overload capability. Furthermore, two Power Supply Modules can be used in parallel to achieve a nominal output up to 60 kW.
The Decentral Access Module (DAM) factory option inside the PSM 520 easily supplies and communicates with the VLT® Integrated Servo Drive ISD® 520 and VLT® Decentral Servo Drive DSD 520 through a hybrid feed-in cable. This enables great flexibility and the freedom to design the servo system according to application needs, whilst supporting modular machine architectures.
VLT® Servo Drive Module SDM 521 or SDM 522
The SDM 521 is a single axis servo drive available in 2 enclosure sizes and 5 power ratings. The SDM 522 is a double axis servo drive available in the smallest enclosure size and 3 power ratings. A wide range of feedback options and sensorless control allows the selection of the preferred PM or ASM motor. Furthermore, the drive modules are equipped with digital I/Os, relay outputs and a Safe Torque Off (STO).
The motion control is integrated in the drives to run the motion sequence independently to release the central PLC. The master can be programmed via IEC 61131-3.
VLT® Expansion Module EXM 520
To support a modular machine architecture the EXM 520 can be used to split the MSD 510 system into 2 cabinets. The maximum permitted distance between the cabinets (cable length) is 5 meters.
Supply and DC-link voltage
Nominal input voltage
3 x 400 - 480 V AC ±10%
DC link voltage
565 - 680 V DC ±10%
Refer to the Selection Guide to find additional technical data, like power and current ratings for SDM 521 and SDM 522
Features and benefits
The extensive portfolio with a mix of central and decentral components fits perfectly into modular machine concepts
Supports various encoder feedback systems and expands the freedom of servo motor selection
Fast and fail-safe wiring concept helps to save installation time and component costs
Innovative mounting concept makes installation quick and failsafe
The smart add-on module approach simplifies machine extension or redesign
Open connectivity to common real time Ethernet protocols allows flexibility, fast process communication and easy system integration
PLCopen Motion libraries and IEC 61131-3 programming provide a standardized and easy system approach across controller platforms
Comprehensive real-time system data from each component strongly supports predictive and preventive machine maintenance
Documents
| Type | Name | Language | Valid for | Updated | Download | File type |
|---|---|---|---|---|---|---|
| Brochure | Engineering - Chemical and Pharma | English | Multiple | 18 May, 2022 | 37.7 MB | |
| Brochure | Engineering - Chemical and Pharma - German | German | Multiple | 14 Jul, 2023 | 37.8 MB | |
| Fact sheet | VLT FlexMotion | English | Multiple | 21 Aug, 2025 | 1.6 MB | |
| Brochure | VLT FlexMotion SG | English | Multiple | 21 Aug, 2025 | 12.7 MB |
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