Low Voltage Variable Frequency Drive (LV VFD) is designed to control motor speed and torque by adjusting voltage and frequency, improving energy efficiency and process control in industrial and commercial applications. It supports smooth starting and stopping while reducing inrush current and mechanical stress on motors.
Equipped with advanced monitoring and protection features, LV VFD ensures reliable operation and easy integration with PLC, automation systems, and SCADA. An efficient solution for pumps, fans, conveyors, compressors, and other variable-speed applications.
| Item | Specification |
|---|---|
| 1. General | |
| Application | Speed control of three-phase induction motors |
| Duty | Continuous industrial operation, suitable for harsh environments |
| Applicable Standards |
IEC 61800-2 / IEC 61800-3 / IEC 61800-5-1 IEC 60204-1 – Electrical Safety IEC 61000-6-2, IEC 61000-6-4 – EMC UL / cUL listing (where applicable) |
| 2. Electrical Ratings | |
| Input Voltage | 380 – 480 VAC, 3-phase, ±10% |
| Input Frequency | 50 / 60 Hz ±5% |
| Output Voltage | 0 – Rated input voltage |
| Output Frequency Range | 0 – 400 Hz (minimum) |
| Overload Capacity |
Normal duty: 110% for 60 sec Heavy duty: 150% for 60 sec |
| Efficiency | ≥ 96% at rated load |
| Power Factor | ≥ 0.95 |
| Switching Frequency | Adjustable, 2 – 12 kHz |
| 3. Control & Protection Features | |
| Control Methods |
V/F Control Sensorless Vector Control (SVC) Closed-loop Vector Control (optional) Torque Control |
| Built-in Protections |
Over / under voltage Overcurrent & short-circuit Motor overload (Class 10 / 20 selectable) Ground fault protection Overtemperature (drive & motor) Phase loss / imbalance Stall prevention |
| Start / Stop Functions |
Soft start / stop Adjustable acceleration & deceleration time (0.1 – 600 sec) Flying start function Automatic restart after power loss (programmable) |
| 4. Harmonics & Power Quality | |
| Harmonic Reduction | Built-in DC choke or AC line reactor |
| Total Harmonic Distortion (THDi) | ≤ 35% with built-in reactor |
| Low Harmonic Option | 12-pulse rectifier or Active Front End (AFE), THDi ≤ 5% (optional) |
| 5. Human Interface & Communication | |
| HMI Panel |
LCD / LED display Programming keypad Display parameters: voltage, current, frequency, power, faults, status Detachable keypad (optional) |
| Communication (Standard) | Modbus RTU / Modbus TCP |
| Communication (Optional) | Profibus DP, Profinet, Ethernet/IP, CANopen, DeviceNet |
| PC Software | Parameterization, monitoring, and diagnostics |
| 6. Environmental Conditions | |
| Ambient Temperature | –10°C to +50°C |
| Humidity | 5 – 95% non-condensing |
| Protection Class | IP20 (panel-mounted), IP21 / IP54 (optional enclosure) |
| Altitude | ≤ 1000 m (derating required above 1000 m) |
| 7. Mechanical & Construction | |
| Enclosure Type | Wall-mounted / Floor-standing |
| Cooling Method | Forced air cooling |
| Cooling Fans | Replaceable fans |
| PCB Protection | Coated PCB for harsh environment (IEC 60721-3-3 Class 3C2 minimum) |
| 8. Accessories | |
| Input Reactor | AC line reactor |
| Output Filter | dv/dt filter or sinewave filter (for motor cable length > 50 m) |
| EMC Filter | Class A / Class B |
| Bypass Contactor | Manual or automatic bypass |
| External Interface | External keypad or remote panel |
| Motor Temperature Interface | PT100 / PTC sensor input |