HITACHI LH1 series universal vector frequency converter

HITACHI LH1 series universal vector frequency converter

The Hitachi LH1 series frequency converter is a multi-purpose, universal vector type frequency converter that integrates energy saving, high efficiency, and flexibility. It inherits the excellent genes of Hitachi inverters in the field of drive control, aiming to contribute to the construction of an environmentally friendly society. The LH1 series is not only compatible with the drive of asynchronous motors (IM) and permanent magnet synchronous motors (PM), fully realizing the energy-saving potential of motors, but also achieves "smooth and stable" operating performance through various anti-interference measures and rich application functions. Its product design fully considers the convenience of users, from flexible installation methods to convenient communication wiring, to a variety of optional operators, all reflecting the unremitting pursuit of "simplicity and ease of use".

The driving force of "smoothness and stability": the cornerstone for dealing with complex working conditions

The core advantage of the LH1 series lies in its strong anti-interference ability, ensuring that the motor can operate smoothly and stably under various harsh working conditions.

2.1 Low voltage ride through (instant stop ignore) function

This is a reliable solution provided by the LH1 series to solve the problem of unstable power grids. When the power supply voltage drops, interrupts or loses power instantly, the frequency converter can use the inertia energy of the motor to maintain continuous operation of the equipment. After the power supply is restored, the system automatically returns to normal. This function can effectively ensure the continuity and safety of production in situations where multiple motors are running synchronously or the power grid conditions are poor, especially suitable for large inertia loads such as wind turbines.

2.2 Overcurrent and Overvoltage Suppression Function

The LH1 series is equipped with a high-speed CPU that can detect and process instantaneous overcurrent or overvoltage caused by rapid acceleration, deceleration, and impact loads. It automatically optimizes operating speed, strongly suppresses current and voltage, avoids frequent tripping, achieves strong continuous stable operation, and protects mechanical equipment from impact.

2.3 Optimization Control of Large Inertial Load

For large inertia loads such as fans, the LH1 series provides specialized solutions:

Start the "windproof car": effectively avoiding the problem of the motor not starting properly due to the rotation of the wind blades under the action of airflow (windmill phenomenon).

Parking "rear excitation": Apply excitation during shutdown to achieve fast, efficient, and accurate positioning and parking, improving production efficiency.

Overexcitation rapid stopping: By increasing the excitation of the motor to increase losses, rapid stopping can be achieved without the need for external braking resistors, effectively reducing system costs. It is particularly suitable for situations such as fans and centrifuges that require rapid braking.

Low carbon and efficient energy-saving: the core driving force for the future

The LH1 series has outstanding performance in energy conservation and consumption reduction, maximizing the operating efficiency of the motor through various technological means.

3.1 Compatible with permanent magnet synchronous motor (PM) drive

The LH1 series is seamlessly compatible with asynchronous motor (IM) and permanent magnet synchronous motor (PM) drives. By utilizing the high efficiency characteristics of PM motors, the overall energy efficiency of the system can be significantly improved, achieving a "one in one" drive platform that helps reduce inventory, spare machines, and lower costs.

3.2 High frequency operation and energy-saving mode

Broadband operating range: The output frequency can be smoothly adjusted within the range of 0~590Hz, with a maximum of 590Hz, meeting the requirements of high-speed and high-precision applications such as precision machining.

Energy saving operation mode: Especially suitable for fans and pumps that operate continuously for a long time. This mode adopts Hitachi's unique "U-finding algorithm", which can automatically track the optimal energy-saving working point of the motor, adjust the output voltage and current in real time, maximize the operating efficiency of the asynchronous motor, and achieve energy saving and consumption reduction.

The flexibility of "flexibility and diversity": meeting diverse applications

The LH1 series meets the complex application needs of various fields through rich built-in functions and flexible configuration options.

4.1 Programmable (EzSQ) Functionality

The LH1 series is equipped with powerful EzSQ programmable functionality. Users can customize their functions by creating specialized process programs. This helps simplify the upper device and surrounding circuits, save control cabinet space, and reduce costs. Its performance parameters include:

Execution cycle: 1ms

Simultaneously executing tasks: 5

Programming capacity: Maximum 1024 steps per task, with a total of 7680 bytes for 5 tasks. In conjunction with the Liquid Crystal Operator (VOP), it can also support real-time clock function.

4.2 4-channel independent PID control

The LH1 series has powerful PID control capabilities, and its four independent PID controllers can be flexibly switched and used through terminal functions. This can not only be used for motor control, but can also be freely used as an external PID controller when not needed, saving costs and space. Its rich PID modes include:

Waterproof Hammer Soft Start PID

Boosting sleep/wake-up

Start leak detection

Multi feedback regional centralized control

PID assisted speed superposition (for constant tension control)

Cascade process control (PID1 output can serve as the target value for PID2)

4.3 Flexible installation methods

The LH1 series comes standard with an adjustable L-shaped mounting bracket, which allows for easy through wall installation and improves the space utilization inside the control cabinet, adapting to different on-site layout requirements.

The Convenience of "Simple and Easy to Use": Human Centered Design

The LH1 series embodies care for user experience in every detail of its products.

5.1 Simplified System Wiring

Analog terminal: 0~10V voltage and 4~20mA current signals can be easily switched through DIP switches, without the need for complex parameter adjustments.

RS-485 communication: Standard equipped with 2 sets of Modbus communication terminals (IN/OUT), internally connected, making communication wiring series connection extremely simple and fast. The maximum communication speed can reach 115.2kbps.

Cartridge style accessory card: can support up to 2 option cards at the same time, easy to expand.

Rich I/O interfaces: Provides 3 switchable analog inputs and 2 switchable analog outputs.

5.2 Diversified Operators

Users can choose three different types of operators according to their needs:

Standard digital operator (MOP): meets basic operation and monitoring requirements.

Multi functional LCD display (VOP): supports parameter copying, real-time clock, multilingual display, and is a true color screen with adjustable background color, providing a better human-computer interaction experience.

5.3 IoT correspondence and lifespan diagnosis

Rich communication options: Supports various mainstream fieldbus communication options such as EtherCAT, Ethernet, Profinet, Profibus DP, DeviceNet, CANopen, CC Link, etc., making it easy to access various industrial networks and achieve remote control and information sharing of factory equipment.

Life diagnosis function: Built in life diagnosis function, which can estimate the life of the electrolytic capacitor in the control circuit through internal calculation, and predict the life of the cooling fan to achieve preventive maintenance.

Long life design: The cooling fan and main circuit capacitor are designed to have a lifespan of up to 10 years (under specific environmental conditions), enhancing the reliability of the equipment.

5.4 Other Convenience Features

DC24V power input: When the main power is turned off, external 24V power supply can be used to set parameters, communicate with PLC, or connect debugging software, greatly improving work efficiency.

Data tracking function: When the frequency reaches or an alarm occurs, the internal status of the frequency converter can be recorded in real time, facilitating subsequent operation adjustments and fault analysis.

Forced operation mode (fire mode): In emergency situations such as fires, ventilation fans and water pumps can be forced to operate, and even automatically switched to bypass mode in the event of a major failure in the frequency converter, safeguarding life and property safety.

Product specifications and selection

The LH1 series offers a rich selection of models, covering multiple power ranges of 400V, from 5.5kW to 355kW. Users can refer to the detailed specification table and standard applicable appliance list in the sample to choose the appropriate inverter model and peripheral accessories, such as circuit breakers, contactors, reactors, and braking resistors, based on motor power and application requirements.

Fault diagnosis and protection

The LH1 series has comprehensive protection functions and a detailed fault code system. The sample lists various fault codes from E001 to E112, covering overcurrent, overload, overvoltage, undervoltage, memory faults, communication faults, option faults, etc. Corresponding countermeasure examples and associated parameters are provided, providing strong support for users to quickly locate and solve problems.