INVT GD350A-5R5G/7R5P-4 Fan & Pump Drive VFD

The INVT GD350A-5R5G/7R5P-4 is a high-performance Variable Frequency Drive (VFD) specifically engineered for demanding fan and pump applications. This advanced drive offers exceptional energy efficiency, precise motor control, and robust reliability, making it an ideal solution for optimizing HVAC systems, water supply networks, and various industrial fluid handling processes. Its core advantages lie in its advanced control algorithms, comprehensive protection features, and user-friendly interface, ensuring seamless integration and operation. Key technical parameters include a power rating of 5.5kW/7.5kW (depending on motor configuration), a wide input voltage range, and multiple programmable I/O options for versatile system integration.

Product Specifications

| Feature                 | Specification                                                                |

| :---------------------- | :--------------------------------------------------------------------------- |

| Model                   | INVT GD350A-5R5G/7R5P-4                                                      |

| Rated Power (kW)        | 5.5 (for 5R5G), 7.5 (for 7R5P)                                               |

| Input Voltage Range     | 380V/400V/415V ±10% (3-Phase)                                                |

| Output Frequency Range  | 0-300 Hz                                                                     |

| Control Method          | V/f Control, Vector Control (Sensorless), Closed-loop Vector Control         |

| Overload Capacity       | 150% for 60s, 180% for 10s                                                   |

| Protection Functions    | Over-voltage, Under-voltage, Over-current, Overload, Overtemperature, etc.   |

| Communication Options   | RS485 (Modbus RTU) standard, optional fieldbus modules                      |

| Mounting                | Wall-mount, Cabinet-mount                                                    |

| Operating Temperature   | -10°C to +40°C (derating above +40°C)                                        |

| Dimensions (H x W x D)  | Varies by model, consult documentation                                       |

Core Features & Market Positioning

The INVT GD350A-5R5G/7R5P-4 distinguishes itself in the competitive VFD market through its sophisticated motor control capabilities, particularly its advanced sensorless vector control, which delivers superior torque response and speed accuracy without the need for motor feedback devices. This translates to significant operational benefits for fan and pump systems, including smoother operation, reduced mechanical stress, and enhanced energy savings, especially under varying load conditions. Its robust design and comprehensive protection mechanisms, such as built-in dynamic braking and advanced fault diagnostics, position it as a reliable and durable solution for harsh industrial environments. The drive's emphasis on energy efficiency is a key selling point, aligning with global trends towards sustainable industrial practices and operational cost reduction.

Key Application Scenarios

This VFD is exceptionally well-suited for a wide array of fan and pump applications where precise speed control and energy optimization are paramount. Common use cases include variable speed pumping in municipal water supply and wastewater treatment plants, where maintaining constant pressure or flow rates with minimal energy expenditure is critical. In HVAC systems for commercial buildings and industrial facilities, the GD350A-5R5G/7R5P-4 effectively manages airflow and water circulation, leading to substantial energy savings and improved comfort control. It also finds application in industrial process control for fluid transfer, ventilation systems in mines, and cooling towers, where dynamic adjustment of motor speed based on system demand is essential for efficient operation.

Practical System Integration Guidance

Integrating the INVT GD350A-5R5G/7R5P-4 into existing systems is streamlined due to its flexible I/O configuration and standard communication protocols. For wiring, ensure all power connections (input and output) are made securely to the designated terminals, adhering strictly to the voltage and current ratings. Grounding is critical for safety and optimal performance; connect the drive's ground terminal to a reliable earth ground. For control signal wiring, utilize shielded twisted-pair cables to minimize electromagnetic interference, especially for analog inputs/outputs and digital signals.

When programming, the drive's intuitive keypad interface and optional PC software allow for easy parameter configuration. Key parameters to set initially include motor data (rated power, voltage, frequency, poles), desired control mode (V/f or vector), and acceleration/deceleration times. For pump applications, configuring PID control loops is often beneficial to maintain setpoint pressure or flow automatically. The drive's built-in RS485 port supports Modbus RTU, facilitating integration into SCADA systems or Building Management Systems (BMS) for remote monitoring and control.

Operation and Risk Mitigation

Safe and efficient operation of the INVT GD350A-5R5G/7R5P-4 involves understanding its protection features and adhering to installation guidelines. The drive incorporates numerous protection functions, including overcurrent, over-voltage, under-voltage, overload, and over-temperature, which automatically shut down the drive to prevent damage. It is crucial to ensure proper ventilation around the VFD to prevent overheating, especially in enclosed cabinets. Regular visual inspections of connections and periodic checks of parameter settings are recommended maintenance practices.

Familiarity with common fault codes is essential for rapid troubleshooting. For instance, an "OL" (Overload) fault typically indicates that the motor is drawing more current than the drive is configured to allow for an extended period, possibly due to mechanical binding or an undersized motor. An "OV" (Over-voltage) fault might occur during deceleration if the motor's back EMF exceeds the drive's DC bus voltage limit and no braking resistor is employed or insufficient. Consulting the user manual for specific fault code explanations and recommended corrective actions is vital for minimizing downtime.

Scalability & Long-Term Value

The INVT GD350A-5R5G/7R5P-4 offers significant scalability and long-term value through its robust design and compatibility with emerging industrial technologies. Its modular construction and the availability of various communication modules (e.g., Profibus, DeviceNet) allow for seamless integration into more complex automated systems and IIoT platforms. This adaptability ensures that the drive can remain a core component even as plant infrastructure evolves. The drive's inherent energy efficiency contributes directly to reduced operational expenditure over its lifespan, providing a strong return on investment.

Furthermore, INVT's commitment to firmware updates and ongoing product development ensures that users can benefit from performance enhancements and new features. The GD350A-5R5G/7R5P-4’s ability to precisely control motor speed not only saves energy but also extends the mechanical life of pumps and fans by reducing stress and wear associated with direct-on-line starting and constant speed operation. This long-term reliability and the potential for integration with digital twins and predictive maintenance solutions underscore its value as a future-proof industrial component.

Frequently Asked Questions

Q1: How do I select the correct INVT GD350A-5R5G/7R5P-4 model for my application?

The model selection depends primarily on the motor's power rating. Ensure the drive's rated power (e.g., 5.5kW for GD350A-5R5G, 7.5kW for GD350A-7R5P) meets or exceeds the motor's nameplate power.

Consider the application's duty cycle; a higher overload requirement might necessitate a slightly oversized drive. Also, evaluate the input voltage availability at your site.

Check the required control features (V/f, sensorless vector) and any specific communication protocols needed for integration with your control system.

Q2: What are the key benefits of using sensorless vector control on the GD350A-5R5G/7R5P-4?

Sensorless vector control offers precise motor speed and torque regulation without requiring an encoder. This feature significantly enhances system performance by providing excellent dynamic response.

It allows for a wider speed range and better low-speed torque, crucial for applications like precise flow control in pumps or maintaining consistent airflow. This reduces wear on mechanical components.

The absence of an encoder simplifies installation, reduces potential failure points, and lowers overall system cost, making it a highly practical choice for many fan and pump setups.

Q3: How can I optimize energy savings with the INVT GD350A-5R5G/7R5P-4?

Ensure the drive is programmed with accurate motor parameters and that the control mode is set appropriately, typically sensorless vector for maximum efficiency. Utilize variable speed operation to match motor output to actual system demand, rather than running at full speed and throttling.

Implement functions like the drive's built-in energy-saving mode or sleep/wake functions for pumps and fans that can operate intermittently. Optimize acceleration and deceleration ramps to avoid unnecessary energy spikes.

Consider using a braking resistor for applications with frequent deceleration or high inertia loads to recapture braking energy more effectively, though for most fan/pump apps this is less critical than flow/pressure matching.

Q4: What is the typical input voltage range for this VFD?

The INVT GD350A-5R5G/7R5P-4 typically operates on a three-phase industrial power supply. Its standard input voltage range is usually around 380V to 415V.

It's important to verify the specific voltage requirements for your region and ensure your incoming power aligns with the drive's specifications to prevent damage. A tolerance of ±10% is common.

Always consult the product's detailed datasheet or label for the exact input voltage and frequency ratings applicable to your specific unit.

Q5: Can the GD350A-5R5G/7R5P-4 be controlled remotely?

Yes, the drive supports remote control and monitoring capabilities. It comes standard with an RS485 communication port, enabling communication via the Modbus RTU protocol.

This allows the VFD to be integrated into SCADA systems, PLCs, or Building Management Systems (BMS) for remote parameter adjustment, start/stop commands, and status monitoring.

Optional communication cards are available for other industrial fieldbus protocols like Profibus, DeviceNet, and Ethernet/IP, offering even greater flexibility for integration into diverse automation architectures.

Q6: What are common troubleshooting steps for an "OL" (Overload) fault?

An "OL" fault indicates the drive is detecting excessive current draw, often due to mechanical resistance or an undersized motor. First, check if the motor is mechanically bound or if there are blockages in the pump or fan system.

Verify that the motor nameplate data programmed into the VFD accurately reflects the motor's specifications, particularly the rated current and power. Ensure the overload protection settings within the drive are correctly configured for the motor.

If the issue persists, the motor itself may be faulty, or the connected load might exceed the drive's or motor's continuous capacity. Consider a motor with a higher power rating or a VFD with a higher current rating.

Q7: How do I set up PID control for a pump application?

To set up PID control, first enable the PID function within the drive's parameters. Configure the feedback input (e.g., an analog pressure transmitter connected to an analog input) to serve as the process variable.

Define the setpoint for the desired pressure or flow. Then, tune the PID parameters (Proportional gain, Integral time, Derivative time) to achieve stable and responsive control without oscillation or excessive overshoot.

The GD350A-5R5G/7R5P-4 often provides auto-tuning features to help in finding optimal PID parameters, simplifying the commissioning process. Consult the manual for specific parameter locations.

Q8: What safety precautions should be taken when installing this VFD?

Always disconnect power before performing any wiring or maintenance. Ensure the VFD is properly grounded to prevent electrical hazards and interference.

Install the drive in a well-ventilated area, away from corrosive or flammable materials, and within the specified ambient temperature range to prevent overheating. Follow all local electrical codes and regulations during installation.

Use appropriate personal protective equipment (PPE) and be aware of stored energy in the DC bus capacitors, which can remain charged even after power is removed. Allow adequate discharge time.

Q9: Can this VFD be used with single-phase motors?

The INVT GD350A-5R5G/7R5P-4 is designed for three-phase motors and requires a three-phase input power supply. It is not designed to directly control single-phase motors.

Using a three-phase VFD with a single-phase motor will likely result in motor damage and is not recommended. For single-phase motor applications, a VFD specifically designed for single-phase motors or an appropriate motor starter would be required.

If your application necessitates a single-phase motor, you must use a compatible drive solution. There are some specialized configurations or external devices, but generally, this VFD series is for three-phase motor control.

Q10: How do I upgrade the firmware on the GD350A-5R5G/7R5P-4?

Firmware upgrades typically involve downloading the latest firmware file from the manufacturer's official website. This file is often a .hex or similar format.

The upgrade process is usually performed via the drive's communication port (RS485) using specialized PC software provided by INVT, or sometimes via a USB interface if available on newer models or specific versions.

Follow the manufacturer's detailed instructions precisely during the firmware update process, ensuring a stable power supply and uninterrupted communication to avoid corrupting the drive's firmware.