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HomeMy WebLinkAbout200035 VARIABLE FREQUENCY DRIVESTHE KENT 20 00 35 - 1 THE KENT Issue Date 05.09.18 VARIABLE FREQUENCY DRIVES THE KENT SECTION 20 00 35 - VARIABLE FREQUENCY DRIVES PART 1 - GENERAL 1.01 RELATED SECTIONS: A. Drawings, general provisions of the Contract, including General and Supplementary Conditions, and Division-1 Specification Sections and Division 21, 22, and 23 Specification Sections, apply to work of this Section. B. This section applies to Division 21, 22 and 23 Specification Sections. 1.02 SUMMARY: A. Furnish complete variable frequency drives as specified herein for the equipment designated on the drawing to be variable speed. All standard and optional features shall be included within the VFD enclosure, unless otherwise specified. 1.03 RELATED DOCUMENTS: A. Related Sections: Separate electrical components and materials required for field installation and electrical connections are specified in Division 26. 1.04 REFERENCES: A. IEEE 519 - 1992 B. FCC Part 15, Class A C. UL 508, ETL D. The current edition of The National Electrical Code: 1.05 SUBMITTALS: A. No separate submittal is required. Submit product data for motors, starters, and other electrical components with submittal data required for the equipment for which it serves, as required by the individual equipment specification sections. 1.06 QUALITY ASSURANCE: A. The VFD and options shall be tested to ANSI/UL Standard 508. The complete VFD, including all specified options, shall be Listed by a nationally recognized testing agency such as UL, C- UL, ETL or CSA. B. To ensure quality and minimize infantile failures at the jobsite, the complete VFD shall be tested by the manufacturer. The VFD shall operate a dynamometer at full load and the load and speed shall be cycled during the test. All optional features shall also be functionally tested at the factory. THE KENT 20 00 35 - 2 THE KENT Issue Date 05.09.18 VARIABLE FREQUENCY DRIVES THE KENT C. Variable frequency drives and related motors shall provide compatible and quiet operation. All manufacturers of variable frequency drives shall be responsible for proper operation of their drives to the satisfaction of the Architect/Engineer. D. All motors used with variable frequency drives shall be “Premium efficiency” and shall be VFD compatible. All motors used with variable frequency drives shall have a grounded rotor to prevent arcing of the bearings. 1.07 MANUFACTURER’S QUALIFICATIONS: A. Manufacturers regularly engaged in the manufacture of variable frequency drives, of type and sizes required, whose products have been in satisfactory use in similar service for not less than 3 years. 1.08 WARRANTY: A. The variable frequency drive shall be warranted by the manufacturer for a period of two years from date of initial operation. B. The warranty shall include all parts, labor, travel expenses, and living expenses incurred by the manufacturer to provide factory authorized on-site service. PART 2 - PRODUCTS 2.01 ACCEPTABLE MANUFACTURERS: A. Manufacturers: Subject to compliance with requirements, provide products by one of the following: 1. ABB Group 2. Danfoss 3. Eaton 4. Square D 5. Toshiba 6. Yaskawa 2.02 PULSE WIDTH MODULATED DRIVES: A. General: 1. Only drives which utilize Insulated Gate Bipolar Transistors (IGBT) technology shall be acceptable. 2. Where installations require that the variable frequency drive be installed at a distance greater than 200 feet from the motor being controlled, the manufacturer shall provide filters to eliminate noise and transmission loss. 3. Motor noise as a result of the variable frequency drive shall be limited to three dB over across-the-line operation, measured at three feet from the motor’s center line. PWM type drives shall include RFI filters. THE KENT 20 00 35 - 3 THE KENT Issue Date 05.09.18 VARIABLE FREQUENCY DRIVES THE KENT B. Basic Design: 1. The VFD shall convert incoming 60 Hz, three-phase AC power into a variable frequency and voltage for stepless speed control of three phase AC motors from 10% to 100% of the motor’s 60 Hz speed. The motor current shall closely approximate a sine wave. Motor voltage shall be varied with frequency to maintain desired motor magnetization current suitable for fan or pump control. 2. An advanced sine wave approximation and voltage vector control shall be used to allow operation at rated motor shaft output at nominal speed with no derating. This voltage vector control shall minimize harmonics to the motor to increase motor efficiency and life. 3. The VFD shall include a full-wave diode bridge rectifier and maintain a fundamental power factor near unity regardless of speed or load. 4. The VFD shall have a DC link reactor to minimize power line harmonics. VFDs without a DC link reactor shall provide a 3% impedance line reactor. 5. The VFD’s full load amp rating shall meet or exceed NEC Table 430-150. The VFD shall be able to provide full rated output current continuously, 110% of rated current for 60 seconds and 220% of rated current for up to 1 second while starting. 6. An automatic energy optimization selection feature shall be provided standard in the drive. This feature shall reduce voltages when lightly loaded and provide a 3% to 10% additional energy savings. 7. Input and output power circuit switching can be done without interlocks or damage to the VFD. 8. VFD shall be housed in a metal NEMA 1 enclosure. C. Protective Features: 1. Class 20 I2t electronic motor overload protection for single motor applications and thermal-mechanical overloads for multiple motor applications. 2. Protection against input transients, loss of AC line phase, short circuit, ground fault, overvoltage, under voltage, drive over temperature and motor over temperature. The VFD shall display all faults in plain English. Codes are not acceptable. 3. Protect VFD from sustained power or phase loss. The VFD shall incorporate a 5 second control power loss ride through to eliminate nuisance tripping. 4. The VFD shall incorporate a motor preheat circuit to keep the motor warm and prevent condensation build up in the stator. 5. Drive shall have semi-conductor rated input fuses to protect power components. 6. The drive shall be fitted with output line reactors to limit the rate of output voltage rise over time (dV/dt), reduce motor operating temperature and RFI and EMI. To prevent breakdown of the motor winding insulation, the dV/dt must be below 1500 V/msec per IEC recommendations. The supplier shall include with the quotation the dV/dt values of the drive. 7. Drive shall catch a rotating motor operating forward or reverse up to full speed. 8. VFD shall be rated for 100,000 amp interrupting capacity (AIC). D. Interface Features: 1. Local/Hand, Stop/Reset and Remote/Auto selector switches shall be provided to start and stop the drive and determine the speed reference. 2. Provide a 24 V DC, 40 mA max, output signal to indicate that the drive is in Remote/Auto mode. 3. Digital manual speed control. Potentiometers are not acceptable. 4. Lockable, alphanumeric backlit display keypad can be remotely mounted up to 10 feet away. 5. A red FAULT light and a green POWER-ON light shall be provided. THE KENT 20 00 35 - 4 THE KENT Issue Date 05.09.18 VARIABLE FREQUENCY DRIVES THE KENT 6. A quick setup menu with preset parameters shall be provided on the drive. 7. The drive shall be fitted with an RS 485 serial communications port and be supplied with software to display all monitoring, fault, alarm and status signals The software shall allow parameter changes to be made to the drive settings as well as storage of each controller’s operating and setup parameters. 8. A USB port for connection of a personal computer shall be provided. 9. Set point control interface (PID control) shall be standard in the unit. 10. Floating point control interface shall be provided to increase/decrease speed in response to switch closures. 11. An elapsed time meter and kWh meter shall be provided. 12. The following displays shall be accessible from the control panel in actual units: Reference Signal Percent, Output Frequency, Output Amps, Motor HP, Motor kW, kWhr, Output Voltage, No Load Warning, DC Bus Voltage, Drive Temperature (% until trip) and Motor Speed in engineering units per application (in percent speed, GPM, CFM...). 13. Drive will sense the loss of load and signal a no load/broken belt warning or fault. 14. The VFD shall store in memory the last 8 faults and record all operational data. 15. A minimum of four programmable digital inputs shall be provided for interfacing with the systems control and safety interlock circuitry. Provide a normally open dry contact interface for interlock with the building fire alarm system. 16. Two programmable relay outputs shall be provided for remote indication of drive status. 17. Two programmable analog inputs shall be provided and shall accept a direct-or- reverse acting signal. Analog reference inputs accepted shall include 0-10 V dc, 0-20 mA and 4-20 mA. 18. Two programmable analog outputs shall be provided for indication of drive status. These outputs shall be programmable for output speed, voltage, frequency, amps, and input kW. 19. Provide micro switch(es) for installation in all disconnect switches on load side of VFD. E. Adjustment Capabilities: 1. VFD shall have an adjustable carrier frequency to optimize motor and VFD operation and reduce motor noise. 2. Three variable-torque V/Hz patterns shall be provided with the ability to select a constant torque start pattern for each of them. 3. A selection of preset speeds shall be provided. 4. Programmable acceleration and deceleration ramps shall be provided. The shape of the curves shall be adjustable. 5. Four current limit settings shall be provided. 6. If VFD trips on one of the following conditions, the VFD shall be programmable for automatic or manual reset: under voltage, overvoltage, current limit, inverter overload and motor overload. 7. The number of restart attempts shall be selectable from 0 through 10 and the time between attempts shall be adjustable from 0 through 10 minutes. F. Manual Bypass: 1. Provide a manual bypass consisting of a door interlocked main fused disconnect pad lockable in the off position that removes power from both the bypass and the VFD, a built-in motor starter and a four position DRIVE/OFF/LINE/TEST switch controlling three contactors. a. In the DRIVE position, the motor is operated at an adjustable speed from the drive. b. In the OFF position, the motor and drive are disconnected. THE KENT 20 00 35 - 5 THE KENT Issue Date 05.09.18 VARIABLE FREQUENCY DRIVES THE KENT c. In the LINE position, the motor is operated at full speed from the AC power line and power is disconnected from the drive, so that service can be performed. d. In the TEST position, the motor is operated at full speed from the AC line power. This allows the drive to be given an operational test while continuing to run the motor at full speed in bypass. 2. Drives utilizing two contactor bypass are acceptable provided they incorporate a service switch on the input to the VFD to allow the functionality of the four position switch as described above. 3. Customer supplied normally closed dry contact shall be interlocked with the drives safety trip circuitry to stop the motor whether in DRIVE or BYPASS mode in case of an external safety fault. 4. Provide separate time-delay fusing for manual bypass circuit of drive in addition to standard circuitry fusing. G. Service Conditions: 1. Ambient temperature, -10 to 40°C (14 to 104°F). 2. 0 to 95% relative humidity, non-condensing. 3. Elevation to 3,300 feet without de-rating. 4. AC line voltage variation, -10 to +10% of nominal with full output. 5. No side clearance shall be required for cooling of wall mount units and all power and control wiring shall be done from the bottom. 6. Drive shall be capable of operating a motor up to 1,000 feet away without de-rating or field modification. H. Project Specific options: 1. Provide manufacturer’s remote operator’s panel for control of all unit functions at remote location. Remote panel shall be located adjacent to the temperature control panel controlling the related fan or pumping system. PART 3 - EXECUTION: 3.01 INSPECTION: A. Examine areas and conditions under which variable frequency drives are to be installed. Do not proceed with work until unsatisfactory conditions have been corrected. 3.02 INSTALLATON: A. Except as otherwise indicated or specified, install variable frequency drives in accordance with the manufacturer’s installation instructions and recognized industry practices to insure that products serve their intended function. B. Coordinate installation work with all other contractors as necessary for proper interface of mechanical, electrical, and temperature control work. C. Install electrical devices furnished by the manufacturer specified to be factory mounted. Furnish a copy of the wiring diagram to the electrical contractor. THE KENT 20 00 35 - 6 THE KENT Issue Date 05.09.18 VARIABLE FREQUENCY DRIVES THE KENT D. Verify that the electrical wiring installation is in accordance with the manufacturer’s submittal and installation requirements of Division 26 Sections. Verify proper rotation of fan wheels and pump impellers. Do not proceed with equipment start-up until wiring installation is acceptable to the equipment installer. 3.03 START-UP: A. Furnish start-up commissioning of the variable frequency drive by a factory certified technician who is experienced in start-up and repair service. The commissioning personnel shall be the same personnel that will provide the factory service and warranty repairs at the customer’s site. Sales personnel and other agents who are not factory certified technicians for drive field repair shall not be acceptable as start-up agents. B. Start-up services shall include checking for verification of proper operation and installation for the variable frequency drive, its accessories, and its interface wiring to the building control system. Included in this service shall be the following: 1. Verification of contactor wire terminations to the variable frequency drive and its optional circuitry. 2. Installation verification for proper operation and reliability of the variable frequency drive, the related motor, and the building temperature control system. 3. Measurement for verification of proper operation on each of the following items: a. Motor voltage and frequency. b. Verification of proper motor operation. c. Control input for proper building temperature control system interface and control calibration. d. Calibration check for minimum speed, maximum speed, acceleration and deceleration rates. 3.04 TRAINING: A. Provide the services of a factory certified technician to train the owner’s operator on the operation and service diagnostics of the variable frequency drive. B. Training shall be for not less than two hours for each type of drive furnished. C. Schedule training with the Owner, providing at least 7 days’ notice to the Engineer prior to the training date. END OF SECTION