2420 Integrated Performance AC Drive
The 2420 is an all-digital pulse-width-modulated (PWM) AC drive that provides superior control of three-phase AC motors. Its revolutionary technology and design make it the optimum solution where superior performance, flexibility, and ease of operation are important.
A unique design incorporating a proprietary digital current regulator and a state-of- the-art controller allows the 2420 to operate any AC induction, AC synchronous, or brushless DC motor without the current-loop setup required by conventional drives. Digital space vector control can be selected for reduced motor noise and low current ripple.
The 2420 is extremely flexible and can accommodate a wide range of servo applications. It can be configured to control torque, velocity, or position in applications requiring either constant-, variable-, or extended-torque. Extensive controller options enable the analog and digital I/O, feedback, and serial communication capabilities of the drive to be tailored to the requirements of the application.
Once routine electrical connections have been made, simple-to-use auto-tuning features adjust virtually all motor and inertial parameters to the given motor and connected load. Simply enter a few values from the motor nameplate, and the advanced setup routines do the rest. The drive is completely tuned within minutes.
The convenient, integrated design of the 2420 provides space, cost, and energy savings in many applications. The drive package incorporates both rectifier and inverter units. The rectifier is comprised of a full-wave diode bridge, a link choke, a bus-charging circuit, a dynamic braking circuit, and a capacitor bank. The inverter consists of a six-IGBT, four-quadrant PWM amplifier that operates from the DC bus of the rectifier.
Applications that operate in a cyclic fashion may regenerate energy from inertial loads. That energy may be dissipated into a resistor using the dynamic braking control within the unit. Optional capacitor banks can alternately be used to store and recycle the regenerative energy.
The 2420 incorporates a link choke that provides near-unity overall power factor and low harmonic line currents at all motor speeds.
Application software determines the specific features and operation of the 2420. A wide variety of general-purpose and application-engineered software options enables each drive to be tailored to specific customer requirements. Software is available for such applications as test stands, elevators, press feeders, winders, rotary cutoffs, spindles, flying cutoffs, and wire drawing, to name a few. Further customization is possible with many programs using UEdit™, a Windows-based programming tool that allows users to extend an application using ladder diagrams and function blocks.
Optically Isolated Digital I/O
All digital inputs and outputs are optically isolated. Depending upon the controller, as many as 32 individually isolated digital I/O are locally provided, each of which can be programmed by the application to be an input or output. The voltage of each can be selected from a wide range of AC and DC values.
The 2420 can operate with or without a feedback transducer. An incremental encoder is typically used for feedback, although absolute encoders, resolvers, and serial sincos encoders are also supported. Transducerless operation is offered for less demanding velocity-loop applications.
- All-digital control for zero drift and repeatable motor operation
- 24-bit DSP computational power for fast, dynamic response
- High-switching-frequency IGBT devices for quiet operation
- Digital current regulator for high-speed operation and fast response
- Digital space vector control for reduced motor noise and low current ripple
- Flux vector control for full torque from zero to rated speed
- Servo loop operation for precise velocity, position, or torque control
- Field weakening at constant horsepower up to four times base speed
Ease of Installation, Setup, and Maintenance
- Complete, self-contained package requires few option boards
- Identical control boards across full power range reduces spare parts
- Snap-in signal connections for ease of wiring
- Automated setup feature requires no chart recorders or meters
- Software calibration and adjustment eliminates tuning components
- Software input and output scaling eliminates potentiometers
- Automated hardware configuration check
Ease of Use
- Full keypad for easy entry of application-specific setup adjustments
- Two line by 24-character/line descriptive, plain-English display
- Process variable display in bar graph and engineering units
- Comprehensive plain-language, self-diagnostic message display
- Real-time motion information and historical fault log
- RS-232/422/485 for communication with process controllers
- Optional software for managing the drive from a personal or handheld computer
- Tolerant of AC line fluctuations
- Extensive electronic protection circuits reduce failures
- Optically isolated signals for high noise immunity
- S-curve acceleration reduces shock and extends equipment life
- Fiber-optics for noise-free serial communication
- Designed to meet or exceed accepted international standards