SVX Industrial Variable Frequency Drives
Modern industries need extremely compact and energy efficient variable frequency drives which ensure future configurability as well. EATON has introduced a variety of variable or adjustable frequency drives that can be used for HVAC, industrial, waste, and water treatment plants, etc. so machines could perform as per requirements.
EATON’s SVX series brings about a wide range of variable frequency drives – equipped with sensorless vector control technique which makes these drives suitable for high speed applications that could also contain multiple drive systems. Other important features of this drive series are the presence of application-specific integrated circuits (ASIC), and an adaptive motor model to estimate real-time parameters. SVX drives are designed with three major modules, namely power module, control module, and keypad module – each of these having unique features and sub-modules or subsystems.
Here, various important characteristics of SVX industrial variable frequency drives are discussed briefly to guide respective users.
A) Electrical Specifications
Electrical specifications of SVX drives mainly pertain to its power module.
- Power Rating: Different models of VFD drives in the SVX series are available in a range of power ratings starting from 1hp and going up to 2200hp making these drives suitable for small to big load applications.
- Voltage Configurations: SVX industrial drives are available in three voltage configurations – 230V, 480V, and 575V being the nominal voltages. However these 3 types can operate under-voltage ranges of 208 to 240V, 380 to 500V, and 525 to 690V respectively.
- Presence of Line Reactor: For noiseless, accurate, and energy-efficient operation of electric drives, it is necessary to feed them with smooth current waveforms. To fulfill this agenda, SVX drives are equipped with a 3% line reactor embedded to ensure high-quality, smooth current waveforms to an attached machine.
- Braking Chopper Circuit: To dissipate extra energy and to maintain DC bus voltage at the required level, the braking chopper circuit is integrated with power modules of the SVX drives. This circuit is mainly used when there is regenerative energy.
- EMC Filtering: SVX drives also have EMC filters so main supply lines provide expected current waveform and don’t get affected by electromagnetic interference. This filter is usually a low pass filter that simply removes noise.
- Safety Features: SVX industrial Variable Frequency Drives include a range of safety features to protect load and SVX drives. These protection mechanisms include overcurrent, under-voltage, over-temperature, motor overload, motor stall, and motor underload protection. SVX series drives also provide input and motor phase supervision. Finally, in the case of Ground fault in motor or motor cables, only the SVX drive is protected. For enhanced safety and accurate operation, these drives fulfill all Electromagnetic Compatibility (EMC) immunity requirements as per EMC standards. All occurring faults and history of faults can be seen on the 9000X drive software window. An indication is also issued on the LCD of the keypad. Moreover, an alarm could be triggered on the occurrence of a fault.
B) Mechanical Specifications
SVX industrial drives are highly compact in design yet very easy to service.
- Frame Size: SVX variable frequency drives come in frame sizes ranging between 4 and 14. Some electrical features might vary with changes in frame size. For example, FR4 to FR6 drives have an option for the installation of internal brake resistors. For bigger frame sizes, the rated output current is also delivered at relatively low temperatures (40°C instead of 50°C).
- Heat Dissipation: In SVX drives, heat is dissipated and the temperature of the drive is controlled in two ways- heatsink, and a fan mounted on the top of the unit. The fan is an easily removable smart sub-system that does not need any wires to make connections or so. The user has the option to make the fan run continuously or after measuring the unit’s temperature or calculating IGBT module temperature.
- Packaging: SVX industrial drives are available in either NEMA 1 or NEMA 12 open design. NEMA 1 design ensures that personnel is protected from accessing hazardous parts and enclosed equipment also remains protected from solid foreign objects. NEMA 12 packaging provides moderate protection to enclosed equipment against dust, falling dust, fibers, and lint. It also protects machinery from dripping water and water splashes.
C) Control Module Specifications
The control part is the major part of a drive system. SVX drives come with control modules laced with smart and advanced features. To add to default features, the control unit of these drives can accept up to five expander and adapter option boards to customize the product as per one’s choice or application requirements.
- Digital and Analog I/O Pins: This module has analog and digital input-output I/O cards. All models in SVX industrial drive series have 6 digital input pins, 2 digital output pins, 2 analog input pins, and 1 analog output pin.
- Communication Card: Through the control module, communication is made possible with the load machine. For this purpose, SVX industrial drives have a communication card, and 3 extension points for extra communication cards (compatibility of communication cards is to be observed by the equipment operator).
- Relay Points: Two relay points are also provided in the control module so that some of the auxiliary drive could be controlled through fault signals (if all other pins are already in use) generated from any of the relay points.
- Electrical Isolation from Power Module: This module is electrically isolated from the power module and operates at 24V DC. This isolation makes this module touch-safe and gives its users the liberty to touch and change I/O pins or communication cards without any safety gear.
- V/Hz Ratio Selection and Automatic Torque Boost Options: Through the control module, a user is given the liberty to select a suitable V/Hz ratio option. Each option has its own unique features and benefits. Anyhow, SVX industrial drives feature an automatic torque boost option for applications where starting friction is high. Furthermore, these drives offer open and closed-loop controls with four different kinds of voltage/frequency curves namely:
- Linear: This is the default setting of the drive which is preferable for constant torque applications.
- Squared: A non-linear setting where torque is made to change with the square of speed.
- Programmable V/Hz Curve: drive operator can input three points to provide the V/Hz curve of one’s own choice.
- Linear with Flux Optimization: A unique feature provided by EATON’s SVX drives that save energy for constant load applications.
- Communication Compatibility: The SVX series of drives support a variety of communication protocols. For example, these drives can communicate with Johnson Controls Metasys N2 network through OPTC2 Fieldbus board, with Ethernet networks through Modbus/TCP Network Card, with BACnet networks through BACnet Network Card, and with industrial protocol networks through EtherNet/IP Network Card. Moreover, this equipment supports Modbus RTU (Remote Terminal Unit) network communications, PROFIBUS network communications, LonWorks network communications, CANopen (Slave) communications, and DeviceNet network communications.
D) Keypad Features
All types of SVX drives come with a user-friendly keypad that is easily removable from the unit. Through this keypad, a local or remote operation of the drive is selected and made.
- Copy and Paste Tool: The smart keypad in SVX drives can be used as a copy and paste tool. Configuration settings can be loaded into this keypad and then loaded into one or several drives easily making it work as a flash drive.
- Display Feature: The keypad of SVX drives also has a screen for displaying mode of operation; phase rotation of output signals (clockwise or counterclockwise); active alarms; any active faults; selection of I/O terminals, keypad control option, communication bus control; and local or remote mode of operation.
- Easy Controllability: Keypad display feature and range of navigation buttons make it convenient for the user to make settings and control the operation of the drive in the desired way. These buttons are used for starting or stopping the drive, easily resetting active faults, making choice between local and remote options, navigating through configurations using arrow buttons, and so on.
- Automatic Backup: For any application in use, its settings and parameters can be backed up into this keypad. Upon changing the application, new settings can be backed up or the previous backup can be maintained. Moreover, these settings can be stored on a PC as a backup file.
E) Software Specifications
SVX industrial drives use 9000X drive software. This software allows commissioning and operation of drive-by loading settings into it. 9000X drive software also enables its users to see fault history as well as active faults, starting and stopping the drive-through operating window.
With this software tool, parameter settings can be made or changed through PC instead of keypad. Moreover, settings can be made in offline mode and saved as a file. Later on, these settings can be loaded into the drive. On the other hand, a database for different drive settings can be built by reading the settings from the frequency converter. Settings of only running applications are loaded into the respective database file.
This software system allows easy monitoring of signals graphically. These graphics can also be printed or saved into a file. Running application mode can also be seen and changed through a software application.
F) Environmental Specifications:
Eaton’s VFD (Variable Frequency Drives) including that from the SVX series are designed to operate under 0 to 95% relative humidity but the environment must be non-corrosive and non-condensing with no dripping water. They are capable of working with full load capacity at altitudes ranging from 0 to 3300 feet above sea level; after this altitude, derating tends to start. These VFD drives can be stored at a minimum temperature of -40°C and a maximum that of 70°C. As far as the operating ambient temperature is concerned, the temperature range is -10 to 50°C for constant torque applications and -10 to 40°C for variable torque applications.
Wide Applicability through Built-in Applications:
SVX series of industrial variable drives comes with seven built-in applications. This feature enhances the versatility of the product giving it a tinge of universal product. Users can easily select an application of choice by going to menu M5. A brief overview of these applications is given to emphasize the usability of SVX drives.
- Basic Application: This application needs a minimum number of parameters to make the drive work. Unit delivered from the manufacturer has basic application settings as default. With this application in use, one can monitor Fieldbus but can’t control it. Most importantly, this application uses almost all safety features that are being utilized for other advanced applications.
- Standard Application: This application features auto restart, DC brake at a stop, programmable start/stop, stall and thermal protection for the motor, reverse signal logic, and much more. Additionally, users have the option to set reference scaling, select switching frequency, and program V/f (voltage frequency) curve while using this application. The standard application is made to work where no specific features are required but basic application feels inadequate. For example; conveyors, fans, and pumps can be used with standard application features.
- Local/Remote Control Application: To select if the product is to be used for remote or local applications, digital input can be given. For different control locations, the user can set frequency through Fieldbus, keypad, or I/O (input/output) terminals. With this application in setting, all outputs can also be programmed freely. This application also features reference scaling, auto restart, DC braking at a stop, acceleration and deceleration ramping, reverse signal logic, overheat and stall protection for the machine along with many other.
- Multi-Step Speed Control Application: SVX industrial variable frequency drives are programmable for 17 different speeds. One basic speed, one jogging speed, and 15 multi-step speeds. This application makes these drives usable for applications where fixed speeds are needed. The user of the drive is given the liberty to select basic speed by giving voltage or current reference at the respective analog input terminal. In this application mode also, all outputs can be programmed freely. All features available for multi-step speed control applications or local/remote applications are available for this application also.
- PID Control Application: SVX variable frequency drives can be used by the owner for PID control applications in two ways either by giving direct reference frequency or PID controller reference. When the unit is configured for this application, the drive can be used easily for smooth control as well as measuring without any additional components. While the drive is configured in this mode, the user can select an analog input signal range. The operator of the drive can also set two frequency limits, torque limit, reference limit, and input and output phase supervisions.
- Multi-Purpose Control Application: With this application, SVX drives can be used for a variety of purposes where several control parameters are to be given. These reference parameters pertain to frequency, field bus communication, multi-step speed, jogging speed, etc.
- Pump and Fan Control Application: This application mode gives its user the ability to control up to 4 auxiliary drives along with one variable frequency drive. PID controller controls the speed of variable frequency drive, issuing start and stop commands for auxiliary drives. Users can configure its control parameters. This mode offers different types of supervision and runs with safety features.