Siemens SINAMICS G120X Infrastructure Drive for Pumps and Fans

Overview

The Siemens SINAMICS G120X is a variable frequency drive that Siemens describes as an infrastructure drive for pumps, fans and compressors. It targets water and wastewater, HVAC, irrigation and agriculture, and industrial chiller and refrigeration duty, and covers power ratings from 0.75 kW up to 630 kW. Siemens built it to be simple to commission, energy-efficient and robust, with application functions for pumps and fans already in the firmware, so many installations need no external pump controller or PLC logic.

Seven Star LLC supplies the Siemens SINAMICS G120X to water utilities, building services contractors, district cooling operators, and oil, gas and industrial plants in the Sultanate of Oman and across the GCC. Our engineers in Muscat size the drive from your motor nameplate, duty and supply voltage, then select filter class, keypad, coating and fieldbus so the order code matches the installation.

Operating Principle of the Siemens SINAMICS G120X

The Siemens SINAMICS G120X rectifies the three-phase supply, stores energy in a DC link and uses an inverter stage to produce a variable-voltage, variable-frequency output for the motor, from 0 V up to about 0.97 times the line voltage. Output frequency reaches 550 Hz on frames FSA to FSG and 150 Hz on FSH and FSJ, depending on control mode. Siemens gives a fundamental power factor of 0.96 to 0.99 and an efficiency of approximately 98%, with IE2 efficiency classification to EN 50598-2 and IEC 61800-9-2.

Motor control is by V/Hz (linear, flux current control, parabolic and eco mode) or sensorless vector control, and the drive runs induction motors, permanent magnet synchronous motors and synchronous reluctance motors. Because pumps and fans follow variable-torque characteristics, the drive is rated for low overload of 110% of base-load current for 60 s, with a high-overload rating of 150% for 60 s for constant-torque duty. Matching speed to actual flow or pressure demand, rather than throttling with valves or dampers, is where most of the energy saving comes from.

Engineering Design of the Siemens SINAMICS G120X

Siemens builds the range in frame sizes FSA to FSJ. Supply options are 200-240 V three-phase from 0.75 to 55 kW, 380-480 V from 0.75 to 560 kW and 500-690 V from 3 to 630 kW, at 47 to 63 Hz. Units are IP20 / UL open type, operate from −20 °C to 45 °C without derating and up to 60 °C with derating, and offer integrated EMC filters of category C2 or C3 depending on frame and voltage. Coating to class 3C2 is standard, with 3C3 available for harsh or corrosive atmospheres, which is relevant for coastal and wastewater sites.

The standard control I/O of the Siemens SINAMICS G120X comprises six digital inputs, two relay outputs, two analog inputs, one analog output, a motor temperature sensor input and a fail-safe STO input, and an optional I/O extension module adds two digital inputs, four relay outputs, one analog input, one temperature input and two analog outputs. Communication options are PROFINET with EtherNet/IP, USS with Modbus RTU and BACnet MS/TP, or PROFIBUS DP. The Intelligent Operator Panel IOP-2, a basic BOP-2 keypad or the Wi-Fi Smart Access Module can be used for setup, and an SD card slot supports parameter backup and cloning.

Key Features of the Siemens SINAMICS G120X

The Siemens technical brochure highlights these capabilities of the Siemens SINAMICS G120X.

• Power range from 0.75 kW to 630 kW across three voltage classes and nine frame sizes.
• Hardware-based Safe Torque Off rated SIL3 to IEC/EN 61800-5-2, with an on/off switch.
• Short-circuit current rating up to 100 kA to the UL 61800-5-1 design.
• Pump functions including multi-pump cascade control, deragging, pipe filling, dry-running, leakage, cavitation and frost protection.
• Fan functions including flying restart, automatic restart, skip frequency bands and fire mode for essential service.
• Energy functions such as eco mode, hibernation or sleep mode, bypass mode and an energy and flow calculator.
• Integrated PID controller, dual ramps, multi-speed setpoints and a real-time clock with programmable timers.
• Protection against phase loss, over- and undervoltage, motor overload, short circuit, ground fault and stall.

Industrial Applications

In Oman the Siemens SINAMICS G120X fits naturally into water infrastructure: booster and transfer pumps in water networks, lift stations and aeration blowers in sewage treatment plants, high-pressure and transfer pumps in reverse osmosis desalination plants, and irrigation pumping on farms. In buildings and district cooling it drives chilled-water pumps, cooling tower fans and air handling units, where BACnet MS/TP lets the drive connect directly to the building management system.

Industrial users in Sohar, Duqm and Salalah apply the drive to process cooling water, compressors, ventilation and firewater jockey pumps, where fire mode and automatic restart support availability. Seven Star LLC supplies the Siemens SINAMICS G120X with engineering support in Muscat, and can quote matching motors such as the Siemens 1LA7 IEC motor. For machine-building duty the compact Siemens SINAMICS G120C is an alternative, and we also supply drives such as the ABB ACS580 where a site standard requires it.

Technical Specifications

The values below for the Siemens SINAMICS G120X are taken from the Siemens technical brochure; the attached data sheet covers the 7.5 kW FSB unit 6SL3220-3YE24-0AF0 as an example rating.

How to Order

To get a quotation for the Siemens SINAMICS G120X, send Seven Star LLC the motor power and current, supply voltage, application (pump, fan or compressor), required fieldbus and the installation environment. We will propose the order number, filter and coating options, confirm stock and lead time for Oman and the GCC, and the Siemens technical brochure and an example data sheet are available to download on this page.

For plant automation around the drive, see the Siemens CPU 1515-2 PN and Siemens SCALANCE XC208 switch.