FC 103

Summary

Product Identification

• Product Line: VLT® Refrigeration Drive FC 103
• Power Range: 1.1–90 kW
• Manufacturer: Danfoss

Approvals and Certifications

The frequency converters are designed in compliance with various EU directives:

• CE Mark: Indicates conformity with applicable EU directives.
  • Low Voltage Directive (2014/35/EU)
  • EMC Directive (2014/30/EU)
  • Machinery Directive (2014/32/EU) - applies to units with integrated safety function.
  • ErP Directive (2009/125/EC)
  • ATEX Directive (2014/34/EU)
  • RoHS Directive (2002/95/EC)
• C-tick Compliance: Indicates compliance with Electromagnetic Compatibility (EMC) standards for Australia and New Zealand.
• UL Compliance: Complies with UL 508C thermal memory retention requirements. (Note: 525–690 V frequency converters are not UL certified.)
• Marine Compliance (ADN): Units with IP55 rating or higher are classified as limited explosion risk electrical apparatus. Specific precautions are required for units with IP20/Chassis, IP21/NEMA 1, or IP54 ratings.

Safety

• High Voltage Hazard: Contains high-voltage components. Installation, start-up, and maintenance must be performed by qualified personnel.
• Unintended Start Hazard: The motor may start unexpectedly. Disconnect mains and use the Off/Reset button before programming.
• Discharge Time: DC-link capacitors can remain charged after power is removed. A waiting time is specified (see Table 1.4 in the document) before service.
• Leakage Current Hazard: Leakage currents exceed 3.5 mA. Proper grounding is mandatory.
• Equipment Hazard: Contact with rotating shafts or electrical equipment can be dangerous.
• Unintended Motor Rotation Hazard (Windmilling): Permanent magnet motors can create voltage if they rotate unintentionally. Block them to prevent this.
• Internal Failure Hazard: Ensure safety covers are in place before applying power.

Product Overview

The VLT® Refrigeration Drive FC 103 is designed specifically for refrigeration applications, featuring:

• Integrated application wizard for commissioning.
• Features like multi-zone cascade control, neutral zone control, floating condensing temperature control, oil return management, multi-feedback evaporator control, dry-run detection, motor alternation, STO (Safe Torque Off), sleep mode, password protection, and Smart Logic Control (SLC).
• Significant energy savings potential, particularly for fan and pump systems, by controlling flow and pressure through variable speed.

The frequency converter operates by converting AC mains power to DC, and then to a variable frequency and voltage AC output for the motor. It comprises four main modules: Rectifier, Intermediate DC bus circuit, Inverter, and Control and regulation.

Control Structures

• Open Loop: Operates based on input commands without feedback from the motor or system.
• Closed Loop: Utilizes an internal PID controller to process system reference and feedback signals, allowing the frequency converter to act as an independent control unit.
• Local (Hand On) and Remote (Auto On) Control: The converter can be operated manually via the Local Control Panel (LCP) or remotely via digital inputs and serial bus.

Reference Handling

• Supports up to 8 internal preset references and external references (analog inputs, pulse frequency inputs, serial bus).
• The active reference can be the external reference, preset reference, setpoint, or a sum of these.
• References can be scaled.

Feedback Handling

• Configurable for advanced control with multiple setpoints and feedback types (single zone/single setpoint, multi-zone/single setpoint, multi-zone/setpoint-feedback).
• Supports PID tuning and auto-tuning for optimization.

Specifications

Detailed technical data, including electrical data for various mains supplies, motor output, ambient conditions, cable specifications, control input/output, and power ratings, are presented in Chapter 7 of the document. Specific values are provided in tables and graphics within that chapter.

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Disclaimer: This summary is based on extracted text and may not include all figures, footnotes, or revisions. Contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

Lenntech datasheet mirror