7.5 kW Frequency Inverter, 1-Phase 220V to 3-Phase 380V

Ventilation Slots

The slots run the full height of both side panels in two groups separated by a horizontal rib, which adds torsional stiffness while maintaining airflow area. The cooling fan — mounted internally above the heatsink — pulls air in through the lower slots and exhausts through the top louvre in a straight vertical chimney, keeping the airflow path as short and unobstructed as possible. Slot edges are deburred and radiused, preventing cable insulation damage if a cable inadvertently contacts the panel during installation, and making the enclosure safe to handle without gloves during maintenance.

LED Display

The LED display sits above the keypad in a clearly demarcated zone, angled slightly for sightlines from below — practical on a drive mounted at head height on a panel. Five digits accommodate the full numeric range of all displayed parameters without scrolling, and all are readable at a glance. The five status indicators along the top row — RUN, LOCAL, Hz, A, V — light in combination to show operating mode and which quantity the main display is currently presenting, so the reading is never ambiguous.

Keypad Panel

Viewed from the front, the panel is recessed slightly within a protective surround that prevents accidental key activation when equipment is moved or serviced. The rotary dial doubles as a push-button — pressing it confirms parameter entries and navigates the display menu — reducing the total number of separate key operations needed during commissioning. For installations where keypad access should be restricted after setup, all parameter groups can be password-protected via P7.08, locking out the MENU and ENTER functions while leaving RUN, STOP, FWD, and REV active for operator use.

Features

1. 17 A Continuous Output: The step up to 17 A from the 5.5 kW model opens the full range of 7.5 kW three-phase motors: large centrifugal pump sets, industrial dust collectors, gang-rip saw main drives, and heavy conveyor systems. 
2. Boost Rectifier Architecture: The internal boost rectifier raises the DC bus voltage above the 220V input level, allowing the inverter stage to synthesise genuine 380V line-to-line AC output.
3. Sensorless Vector Control: The drive continuously estimates rotor flux from measured terminal voltage and current, adjusting output to maintain commanded speed as torque demand changes. For loads like gang-rip saws (where each board cuts differently) or pump sets (where system pressure varies as zones open and close), motor speed holds stable without hunting or sagging.
4. Built-In PID Controller: The onboard PID accepts a 0–10V or 4–20mA feedback signal from a standard pressure, flow, or level transmitter and adjusts motor speed to hold the process variable at setpoint. No external controller is needed — the drive handles the full control loop independently.
5. Automatic Voltage Regulation: Single-phase rural supplies routinely vary by ±10% or more, particularly during peak irrigation or harvest periods when multiple large loads compete on the same feeder. AVR compensates on every PWM cycle, keeping output voltage at the configured 380V regardless of input fluctuation within the ±15% tolerance band.

Use Cases

• Industrial Dust Collectors and Cyclone Extractors: Workshop dust collectors at this power level serve multiple simultaneous machine connections. Variable-speed control allows airflow to be matched to the number of active machines — reducing fan speed (and noise) when only one machine is running, increasing to full speed when all connections are open. The drive's automatic current limit prevents nuisance tripping when a large chip load briefly peaks the motor current.
• Gang-Rip Saws and Industrial Ripping Lines: The main drive motor on a gang-rip saw encounters highly variable torque loads as board width, thickness, and species change between cuts. Sensorless vector control on this drive maintains blade speed through these variations, improving cut quality and reducing motor heating caused by speed-induced over-excitation at light load.
• CNC Router Dust Collectors and Spindle Drives: Users running imported 380V CNC routers on single-phase 220V premises — a common scenario for small production shops and hobbyist CNC installations — use this drive for the dust collector motor while using a separate drive for the spindle. The 7.5 kW rating covers dust collector motors on medium-format routers (1200 × 2400 mm table and larger).
• Water Treatment and Dosing Pump Stations: Variable-speed dosing and transfer pumps in water treatment plants benefit from Modbus integration — flow rate setpoints issued by the SCADA system, actual flow and drive status read back, and fault alerts forwarded to the control room — all over the existing RS-485 cable without additional hardware.

Application Scenarios

HVAC

Industrial Printing

Conveyor Belts

Air Compressors

Q1: What is the difference between the 7.5 kW model and the 5.5 kW model in this series?

Both are GK3000-CS platform drives with identical control features, communication, and protection functions. The 7.5 kW model (GK3000-CS0075G) is rated at 17A output versus 13A for the 5.5 kW (GK3000-CS0055G), a 31% increase in current capacity. Both occupy the same enclosure (330 × 200 × 200 mm) and weigh the same (8 kg). Choose the 7.5 kW model when the motor nameplate reads 7.5 kW / 10 hp, or when the 5.5 kW model would be consistently loaded above 80% of its rated current. Do not rely on the 150% overload rating to cover sustained loads above the 5.5 kW model's continuous rating — the overload margin exists for transient peaks, not continuous operation.

Q2: Can this drive restart automatically after a power interruption?

This depends on the control mode. In two-wire control mode (P0.03 = 1), the drive will restart automatically if the FWD terminal is held closed when power returns — suitable for unattended pump or fan installations where continuous operation is required. In three-wire control mode (P0.03 = 2), the drive will not restart automatically — a new START pulse is required, meeting safety requirements for machinery where unexpected restart could endanger operators. Select the appropriate mode for the application during commissioning.

Q3: My CNC router has a 380V dust collector motor and a 380V spindle — can I run both from one drive?

No — one drive, one motor. Running two motors from a single drive output in independent variable-speed operation is not supported: the drive sees the parallel combination as a single load, sensorless vector control loses accuracy, and individual motor overload protection is unavailable. For a CNC router installation with both a dust collector motor and a spindle motor, each motor requires its own drive. Size the dust collector drive to the dust collector motor nameplate and the spindle drive to the spindle motor nameplate.

Q4: The installation site has significant electromagnetic interference from welding equipment. What precautions are needed?

Install an input EMC filter (Class C2 or better) at the drive's L and N terminals. Use shielded cable for all analog and digital control wiring, with the shield grounded at the drive end only. Keep control cables physically separated from power cables by at least 200 mm, crossing at right angles where separation is not possible. Ground the drive enclosure and motor frame to a common earth point via the shortest possible conductor. If the welding equipment shares the same AC circuit, install an isolation transformer upstream of the drive to break the conducted interference path.