Kollmorgen SERVOSTAR 620-AS Servo Drive for ServoStar

Kollmorgen SERVOSTAR 620-AS: Servo Drive for ServoStar

The Kollmorgen SERVOSTAR 620-AS is a high-performance analog/digital servo drive engineered for seamless integration within the ServoStar motion control platform. Designed to operate as a precision execution-layer component in multi-axis automation architectures, the SERVOSTAR 620-AS delivers consistent torque regulation, velocity control, and position loop closure across demanding industrial environments. Its role within a layered control system extends far beyond standalone drive operation — it functions as a coordinated node within a broader ecosystem of motion controllers, feedback devices, power conditioning modules, and supervisory control networks.

In modern industrial automation, the servo drive occupies a critical position between the motion controller and the mechanical actuator. The SERVOSTAR 620-AS accepts command signals from upper-level controllers such as the Kollmorgen SERVOSTAR S300 or S700 series, translating digital or analog motion commands into precise current waveforms delivered to the connected servo motor. This signal flow — from PLC or CNC controller through the drive to the motor and back through the encoder feedback loop — defines the fundamental architecture of closed-loop motion control. The SERVOSTAR 620-AS is optimized to maintain loop stability across this entire signal chain, supporting both velocity and torque control modes with high bandwidth response.

System architects specifying the SERVOSTAR 620-AS benefit from its compatibility with the broader Kollmorgen ServoStar ecosystem. When paired with the SERVOSTAR CD or SERVOSTAR 600 series drives in multi-axis configurations, the 620-AS maintains consistent electrical and communication characteristics that simplify cabinet wiring, reduce commissioning time, and support long-term spare parts standardization. The drive’s analog command interface allows direct integration with legacy motion controllers while its digital I/O structure supports handshaking with safety relay modules, enabling STO (Safe Torque Off) functionality compliant with machine safety standards.

Power architecture is a foundational consideration in any servo system design. The SERVOSTAR 620-AS operates from a DC bus supplied by a compatible Kollmorgen power supply or regenerative bus module, sharing bus energy with other axes in a common DC bus configuration. This topology reduces overall energy consumption, improves dynamic response during regenerative braking events, and simplifies the power distribution design within the control cabinet. Proper bus capacitance sizing, coordinated with the power supply module and any bus capacitor banks, ensures stable operation across the full duty cycle of the connected servo motor.

Feedback integration is central to the SERVOSTAR 620-AS architecture. The drive supports resolver and encoder feedback devices, enabling compatibility with a wide range of Kollmorgen servo motors including the AKM and Goldline series. The feedback interface provides the drive with real-time rotor position and velocity data, closing the inner current and velocity loops at high update rates. When the drive is integrated with an external motion controller managing the position loop, the feedback data is also transmitted upstream, enabling coordinated multi-axis interpolation and electronic gearing functions.

Network and communication architecture in systems using the SERVOSTAR 620-AS typically involves a supervisory PLC or motion controller communicating over industrial fieldbus networks. While the 620-AS itself operates on analog and digital I/O command interfaces, it is commonly deployed alongside communication gateway modules that bridge the drive’s I/O to higher-level networks such as PROFIBUS, DeviceNet, or CANopen. This gateway architecture allows the SERVOSTAR 620-AS to participate in coordinated motion sequences managed by a central controller, receiving enable signals, speed references, and fault reset commands through the fieldbus network while reporting drive status and fault codes back to the supervisory system.

Long-term maintainability is a key advantage of specifying the SERVOSTAR 620-AS within a standardized ServoStar architecture. Maintenance engineers familiar with the ServoStar platform can apply consistent diagnostic procedures, parameter backup protocols, and replacement workflows across all installed drives. Drive parameters stored in the controller or on portable memory devices can be restored to a replacement unit rapidly, minimizing unplanned downtime. ZYPLC maintains availability subject to RFQ confirmation of the SERVOSTAR 620-AS with full functional testing prior to shipment, supporting both planned maintenance programs and emergency replacement requirements. All units supplied by ZYPLC are covered by a warranty terms confirmed during quotation, providing documented assurance of drive performance and reliability from the date of delivery.

Product Specification Table

System Compatibility Notes

The SERVOSTAR 620-AS achieves its full performance potential when deployed as part of a coordinated ServoStar control architecture. In a typical multi-axis machine tool or packaging line application, the drive operates alongside a Kollmorgen SERVOSTAR S700 master drive or a dedicated motion controller that manages position loop closure and axis interpolation. The S700 or equivalent controller issues velocity or torque references to the 620-AS via analog command signals, while digital I/O lines carry enable, fault, and at-speed status signals between the drive and the controller.

Power distribution in such systems relies on a shared DC bus supplied by a Kollmorgen regenerative power supply module. Bus capacitor banks installed in the cabinet absorb regenerative energy from decelerating axes, reducing stress on the supply and improving overall system efficiency. The SERVOSTAR 620-AS connects to this common bus alongside other ServoStar 600 series drives, maintaining consistent bus voltage across all axes during dynamic motion profiles.

Feedback wiring from Kollmorgen AKM series servo motors connects directly to the SERVOSTAR 620-AS resolver or encoder input, providing rotor position data for inner loop closure. In systems requiring absolute position reference, a Heidenhain or Stegmann absolute encoder may be interfaced through an external feedback converter module, with the converted incremental signal fed to the drive’s encoder input. This configuration supports homing-free operation after power cycling, improving machine startup efficiency.

At the supervisory level, a Siemens S7-300 PLC or equivalent controller manages the overall machine sequence, issuing motion enable commands and monitoring drive fault outputs through a PROFIBUS gateway module. The gateway translates fieldbus commands into the analog and digital signals required by the SERVOSTAR 620-AS, enabling the drive to participate in coordinated production sequences without requiring a native fieldbus interface. Safety functions are implemented through a Pilz PNOZ safety relay module connected to the drive’s STO input, ensuring that the drive de-energizes the motor in response to E-stop or guard door open signals without requiring controller intervention.

HMI integration is provided through a Weintek or Siemens TP series touch panel connected to the supervisory PLC, displaying drive status, axis position, and fault codes retrieved from the controller’s I/O image. Maintenance personnel can access drive diagnostic parameters through the SERVOSTAR setup software connected via the drive’s RS-232 service port, enabling parameter verification and fault log review without interrupting production.

Industrial Application Notes

The SERVOSTAR 620-AS is deployed across a broad range of industrial automation sectors where precise servo motion is required within a structured control architecture. In manufacturing and assembly automation, the drive controls servo axes on robotic welding positioners, precision assembly stations, and CNC machining centers, where consistent velocity regulation and rapid torque response are essential for part quality and cycle time optimization.

In the packaging industry, the SERVOSTAR 620-AS drives servo axes on form-fill-seal machines, cartoning lines, and label applicators, where synchronized multi-axis motion coordinated by a central motion controller determines throughput and format changeover efficiency. The drive’s analog command interface allows direct integration with legacy motion controllers commonly found in installed packaging machinery, extending the operational life of existing equipment without requiring a full controls upgrade.

Power generation and utilities applications deploy the SERVOSTAR 620-AS in valve actuator control systems, turbine governor drives, and pump speed regulation applications where precise torque control and reliable long-term operation are critical. The drive’s compatibility with the ServoStar power architecture and its support for STO safety functions make it suitable for applications subject to functional safety requirements under IEC 62061 or ISO 13849.

In the metals and mining sector, the SERVOSTAR 620-AS is applied in rolling mill positioning drives, conveyor tensioning systems, and ore processing equipment where high dynamic response and robust operation under variable load conditions are required. The drive’s resolver feedback compatibility ensures reliable operation in environments where encoder signal integrity may be compromised by electrical noise or vibration.

Process industries including chemical, petrochemical, and water treatment deploy the SERVOSTAR 620-AS in agitator drives, dosing pump controls, and valve positioning systems integrated within DCS or PLC-based process control architectures. The drive’s analog command interface provides a straightforward integration path with 4-20mA or ±10V analog outputs from process controllers, enabling precise flow and pressure regulation within closed-loop process control loops.

Product Compatibility FAQ

Q1: Is the SERVOSTAR 620-AS compatible with existing ServoStar 600 series installations, and can it share a common DC bus with other drives in the same cabinet?
Yes. The SERVOSTAR 620-AS is designed for compatibility within the ServoStar 600 series platform and supports common DC bus operation with other drives in the series. When integrating a replacement or additional 620-AS into an existing installation, verify that the shared bus power supply is sized to support the combined peak current demand of all connected axes. Bus capacitance and regenerative braking capacity should be reviewed against the updated axis count and duty cycle to ensure stable bus voltage under all operating conditions.

Q2: What commissioning steps are required when replacing a SERVOSTAR 620-AS in an installed system, and how can parameter restoration be accelerated?
Replacement commissioning begins with parameter backup from the original drive using the SERVOSTAR setup software via the RS-232 service port, if the original drive remains functional. If the original drive has failed, parameters should be retrieved from the motion controller’s stored axis configuration or from the site’s maintenance parameter archive. After installing the replacement 620-AS, restore the saved parameter set, verify feedback device wiring and resolver offset calibration, and perform a low-speed jog test before returning the axis to full production speed. ZYPLC supplies all SERVOSTAR 620-AS units with full functional testing completed prior to shipment, reducing the risk of commissioning delays due to drive defects.

Q3: What does the warranty terms confirmed during quotation cover for the SERVOSTAR 620-AS, and what support is available for long-term spare parts planning?
The warranty terms confirmed during quotation provided by ZYPLC covers verified functional performance of the SERVOSTAR 620-AS from the date of delivery, including protection against drive failure under normal operating conditions consistent with the drive’s rated specifications. ZYPLC maintains ongoing stock of the SERVOSTAR 620-AS and related ServoStar series components to support both planned maintenance programs and emergency replacement requirements. For long-term spare parts planning, ZYPLC recommends maintaining at least one spare 620-AS per installed machine or production line to minimize exposure to unplanned downtime. Contact ZYPLC at +86 19859288691 or plc.sales@zyplc.com to discuss volume pricing, consignment stock arrangements, or multi-site supply agreements.