FC111P18KT4 Danfoss VLT HVAC Basic Drive 18.5kW 25HP

Product Overview

The FC111P18KT4 (FC111P18KT4) is a high-efficiency variable frequency drive from the Danfoss VLT® HVAC Basic Drive FC 101/111 series, specifically engineered to provide reliable speed control for 18.5 kW (25 HP) motors. Designed for the unique demands of building automation, this drive excels in managing fans, pumps, and compressors within modern HVAC infrastructures. By utilizing advanced features like Automatic Energy Optimization (AEO) and an efficiency rating of up to 98.1%, the FC111P18KT4 significantly reduces operational energy costs. Its H5 frame size and IP20 chassis design are optimized for high-density cabinet mounting, providing a robust and cost-effective solution for optimizing climate control systems in commercial and industrial facilities.

Suffix & Frame Breakdown

The model designation FC111P18KT4 identifies the specific power and hardware tier:

• FC111: Part of the VLT® HVAC Basic Drive series family.

• P18K: Indicates a typical shaft output of 18.5 kW (25 HP).

• T4: Designed for three-phase mains input between 380 - 480 VAC.

• H5: Refers to the physical frame size (Enclosure IP20), which determines the mounting footprint and terminal capacity.

• IP20: Open-type chassis rating for installation in protected electrical panels.

Technical Specifications

Technical FAQs

How does ambient temperature affect the output of this drive?

The FC111P18KT4 is designed to provide full performance up to 40°C (37.0 A continuous). If your mechanical room or cabinet reaches 50°C, the drive automatically manages its thermal load, with the continuous output current derating to 34.1 A. This ensures the longevity of the power electronics even in warmer climates.

What HVAC-specific software features are included?

This drive includes several "built-in" features to protect your mechanical systems, including the Fire Mode (which keeps the drive running during emergencies to maintain smoke extraction), a flying start function (to catch a spinning fan without tripping), and an Electronic Thermal Relay to prevent motor burnout without requiring external sensors.

Can this drive be integrated into a Building Management System (BMS)?

Yes. The FC 111 series includes standard communication protocols such as BACnet MS/TP and Modbus RTU. This allows the drive to share energy consumption data, pressure/temperature feedback, and maintenance alarms directly with your central facility controller.

Engineering & Installation Guide

• Terminal Wiring: The H5 frame terminals support up to 16 mm² (6 AWG) cable. Ensure that all mains and motor connections are torqued according to the manual to prevent localized heating. For 18.5 kW loads, high-quality copper conductors are recommended to maintain low voltage drop.

• Cabinet Ventilation: With a typical power loss of 456 Watts, this drive generates significant heat. Ensure your control cabinet is equipped with filtered ventilation or a cooling unit capable of dissipating this thermal load. Maintain a minimum vertical clearance of 100 mm for unobstructed airflow through the heat sink.

• Motor Protection: For best results, perform an Automatic Motor Adaptation (AMA) after wiring. This allows the drive to map the motor's reactance and resistance at a standstill, ensuring the VVC+ control algorithm delivers maximum torque and the highest possible energy savings.