Siemens SINAMICS G120C 55kW Compact Frequency Converter

Technical Overview

Compact 55 kW VFD with 380-480 V input, IP20, PROFINET, STO, and 150% overload for precise industrial motor control.

Key Features

Rated output power of 55 kW.
Supports 380-480 V 3AC input voltage range (47-63 Hz).
Offers 150% overload capacity for 3 seconds.
Features integrated PROFINET-PN and EtherNet/IP fieldbus communication.
Includes Safe Torque Off (STO) safety functionality.
Provides IP20/UL open type degree of protection.
Equipped with 6 digital inputs, 2 digital outputs, 1 analog input, and 1 analog output.
Compact dimensions (551 x 275 x 237 mm HxWxD) for space-saving installation.

Technical Specification Matrix

Parameter	Value
Rated Power	55.0 kW
Input Voltage	380-480 V 3AC (+10% / -20%)
Input Frequency	47-63 Hz
Rated Current (LO)	96 A
Rated Current (HO)	85 A
Max. Output Current	165 A
Overload Capability (LO)	150% base load current for 3s, followed by 110% for 57s in a 300s cycle
Overload Capability (HO)	200% base load current for 3s, followed by 150% for 57s in a 300s cycle
Pulse Frequency	4 kHz
Output Frequency (Vector Control)	0-240 Hz
Output Frequency (V/f Control)	0-550 Hz
Degree of Protection	IP20/UL open type
Digital Inputs	6
Digital Outputs	2 (1 relay changeover contact, 1 transistor)
Analog Inputs	1 (Differential, 10 bit resolution)
Analog Outputs	1 (Non-isolated)
Communication Interfaces	PROFINET, EtherNet/IP
Safety Function	Safe Torque Off (STO) integrated
External Supply	24 VDC
Physical Weight (kg)	27
Dimensions L x W x H (cm)	59.5 x 40 x 35

Industrial Applications

1. Industrial Pump Control in Water Treatment Facilities

This drive efficiently controls the speed of high-power 55 kW pumps, matching flow rates to demand and optimizing energy consumption in water treatment plants and municipal water supply systems.

Problem Solved

Reduces energy waste and improves process control by precisely regulating pump motor speed, preventing cavitation and excessive wear on mechanical components, thereby extending equipment lifespan and reducing maintenance needs. The PROFINET interface allows seamless integration into plant control systems.

55 kW380-480 VVariable Frequency DrivePump ControlEnergy EfficiencyFlow Rate RegulationPROFINETProcess Control

2. Conveyor System Management in Logistics Centers

Provides precise speed and torque control for 55 kW conveyor belt motors, enabling smooth acceleration and deceleration, reducing mechanical stress, and integrating with plant automation systems via PROFINET for optimized material flow.

Problem Solved

Minimizes product damage and reduces wear and tear on mechanical components by eliminating sudden starts and stops. The 150% overload capability handles peak loads, while Safe Torque Off (STO) ensures critical safety during maintenance or emergency stops, improving operational safety and efficiency.

55 kWMotor ControlConveyor SystemsSpeed ControlSafe Torque Off (STO)PROFINETOverload CapacityMaterial Handling

3. HVAC Fan Control for Large Industrial Buildings

Regulates the speed of 55 kW fans in large industrial HVAC systems, allowing for demand-controlled ventilation, improving air quality, and significantly reducing heating, ventilation, and air conditioning costs.

Problem Solved

Optimizes building climate control and dramatically lowers energy consumption by precisely adjusting fan speed based on real-time environmental conditions or building occupancy via analog inputs. The integrated STO function enhances safety for maintenance personnel, while IP20 protection is suitable for protected electrical cabinets.

55 kWFan ControlHVACEnergy OptimizationVariable Frequency DriveAirflow RegulationSafe Torque Off (STO)Building Automation