This specification describes a complete Adjustable Speed AC Drive (ASD) used to control the speed and torque of NEMA design B induction motors.
The ASD manufacturer shall supply the ASD and all necessary controls as herein specified.
The ASD shall be manufactured by a company with at least twenty (20) years experience in the production of this type of equipment.
1.2 QUALITY ASSURANCE
The ASD manufacturing facility shall be ISO 9001 and ISO 14001 certified.
All printed circuit boards shall be completely tested before being assembled into the complete ASD. The ASD shall be subjected to a functional test and load test. The load test shall be at full rated load, or cycled load.
The ASD manufacturer shall have an analysis laboratory to evaluate the failure of any component.
The ASD shall meet the following specifications
UL 508A and/or 508C - Underwriter's Laboratory. The ASD shall be UL listed and carry the UL mark.
CAN/CSA-C22 No. 14-M91 - Canadian Standards Association. The ASD shall be C-UL or CSA listed and carry the appropriate mark.
The ASD shall comply with the following European Union’s CE directives. The ASD shall carry CE mark.
EMC Low Voltage Directive 2006/95/EC
EMC Directive 2004/42/EC
Machinery Directive 2006/108/EC
ABB Inc. ACS880 series of AC ASDs
ASD manufacturer must design, manufacture, quality control and life cycle manage all products offered on this project.
ASD vendors that brand label products manufactured by others shall not be allowed.
The Submittals shall include the following information:
Outline Dimensions and Weight.
Customer connection and power wiring diagrams.
Complete technical product description including a complete list of options provided.
The ASD shall be solid state AC to AC inverter controlled device utilizing the latest isolated gate bipolar transistor (IGBT) technology. The ASD shall utilize Direct Torque Control (DTC) as the primary motor control, employing an inner loop torque control strategy that mathematically determines the optimal motor torque and flux every 25 microseconds. The ASD must also provide an optional motor control operational mode for scalar of V/Hz operation.
The benefits that the motor control DTC shall make available for the operation of a NEMA design B induction motor shall be;
Steady state speed accuracy within 1/10th the slip without an encoder, for process repeatability.
100% motor torque from zero speed available for acceleration with the ASD continuous current rating equal to or greater then the motor full load amp rating.
At and below 90% speed, 100% torque is achievable even with 10% low line voltage.
Ability to limit torque to protect the mechanical system with a common single torque setting above and below field weakening.
Ability to provide torque in % of motor shaft torque (with in +/- 4% linearity) on the ASD control panel, analog output or via field bus of actual.
Quiet motor operation for audibly friendly working environment in comparison to other low voltage PWM solutions utilizing a carrier frequency.
Have available the ability to operate in open loop torque control, with an ability to switch between speed and torque control on the fly with the change of state to a digital input.
Have an ability to share load or speed between two or more induction AC motors connected to the same system, when those motors are controlled by separate ASDs.
The ASD shall be rated to operate from 3-phase power at 208 VAC to 240 VAC +10/-10% / 380 VAC to 500 VAC +10/-10% / 525 to 690 VAC (600 VAC, UL and CSA) +10/-10%. The overvoltage trip level shall be a minimum of 30% over nominal, and the undervoltage trip level shall be a minimum 35% under the nominal voltage.
The ASD shall be rated to operate at the following environmental operating conditions: ambient temperature 0 to 40C continuous. ASDs that can operate at 40 C intermittently (during a 24 hour period) are not acceptable and must be oversized. Altitude 0 to 3300 feet above sea level without derating, less than 95% humidity, non-condensing.
The ASD shall be offered from 0.75 HP to 350 HP in similar construction and operation, using the same technology.
The ASD shall be rated to operate from input power from 48Hz to 63Hz.
Output voltage and current ratings shall match the adjustable frequency operating requirements of standard NEMA design A or NEMA design B motors.
The Normal Duty overload current capacity shall be 110% of rated current for one (1) minute out of five (5) minutes.
The Heavy Duty overload current capacity shall be 150% of rated current for one (1) minute out of five (5) minutes.
The ASD efficiency shall be 98% or better of the full rated capability of the ASD at full speed and load.
The latest, most efficient IGBT power technology shall be used. This technology shall be used for all power and voltage ranges offered by the manufacturer.
The ASD shall offer microprocessor based control logic that is isolated from power circuitry.
The ASD shall use the same main control board for all ratings.
Control connections shall remain consistent for all power ratings.
Wall mountable ASDs shall be available from 0.75 to 350HP and have the following features;
Offered in UL Type 1 and NEMA Type 12 wall mountable enclosures
Include a control panel mounted on the front of the ASD
Include coated circuit boards as standard
Include integrated DC choke
Offer option internally mounted braking chopper for use in dynamic braking with 100% continuous duty operation.
Desired optional features shall be furnished and mounted by the ASD manufacturer and shall also be available as field installable kits as an alternative. All optional features shall carry all of the necessary certifications as described in Section 1.03. Field installed kits shall not affect the ASD’s certification.
2.4 OPERATOR INTERFACE
The ASD shall be equipped with a front mounted operator control panel consisting of a four- (4) line back-lit alphanumeric LCD display that is 240x160 pixels. Configurable displays showing, bar graph and meter. Keypad with keys for Run/Stop, Local/Remote, Increase/Decrease, Reset, Menu navigation and Parameter select/edit.
The control panel shall be removable, capable of remote mounting and allow for uploading and downloading of parameter settings as an aid for start-up of multiple ASDs.
The display of the control panel shall have the following features:
All parameter names, fault messages, warnings and other information shall be displayed in complete American English words or standard American English abbreviations to allow the user to understand what is being displayed without the use of a manual or cross-reference table.
Additional languages including French, Spanish, Portuguese, German, Italian, Dutch, Danish, Swedish, Finnish, Russian, Turkish and Chinese shall be selectable.
During normal operation, one (1) line of the control panel shall display the speed reference, and run/stop forward/reverse and local/remote status. The remaining three (3) lines of the display shall be programmable to display the values of any three (3) operating parameters. The selection shall include at least the following values:
Speed/torque in percent (%), RPM or user-scaled units
Output frequency, voltage, current and torque
Power and kilowatt hours
Heatsink temperature and DC bus voltage
Status of discrete inputs and outputs
Values of analog input and output signals
Values of PID controller reference, feedback and error signals
The control panel shall be used for local control, for setting all parameters, and for stepping through the displays and menus.
A copy function to upload and store parameter settings from an ASD and download stored parameter settings to the same ASD or to another ASD shall exist.
An intelligent start-up assistant shall be provided as standard. The Start-up routine will guide the user through all necessary adjustments to optimize operation.
The Start-Up routine shall include “plug and produce” operation, which automatically recognizes the addition of options and fieldbus adapters and provides the necessary adjustment assistance.
The Start-Up routine shall prompt the user for Motor Nameplate Data including power, speed, voltage, frequency and current.
An auto-tune function shall identify the optimal motor tuning parameters for typical applications.
An auto-tune function shall also be available to tune the PID speed regulator loop. Manual adjustments shall also be allowed.
A selection of at least ten (10) preprogrammed application macro parameter sets shall be provided to minimize the number of parameter adjustments required during start-up. Macros offered shall include Factory Default, Hand/Auto, PID Control, Torque Control, Sequential Control, and Fieldbus Control. A selection of four (4) user defined macros shall are also be available.
Selection shall be offered for both 2-wire and 3-wire Start/Stop control.
2.5 PROTECTIVE FEATURES
For each programmed warning and fault protection function, the ASD shall display a message in complete English words or Standard English abbreviations. The five (5) active and most recent fault messages and times shall be stored in the ASD’s fault history.
The ASD shall include internal MOV’s for phase to phase and phase to ground line voltage transient protection.
Output short circuit and ground fault protection rated for 100,000 amps without relying on line fuses shall be provided per UL508C.
Motor phase loss protection shall be provided.
The ASD shall provide electronic motor overload protection qualified per UL508C.
Protection shall be provided for AC line or DC bus overvoltage at 130% of maximum rated voltage or undervoltage at 65% of min. rated voltage.
The ASD shall protect itself against input phase loss.
A power loss ride through feature shall allow the ASD to remain fully operational after losing power as long as kinetic energy can be recovered from the rotating mass of the motor and load.
Stall protection shall be programmable to provide a warning or stop the ASD after the motor has operated above a programmed torque level for a programmed time limit.
Underload protection shall be programmable to provide a warning or stop the ASD after the motor has operated below a selected underload curve for a programmed time limit.
Over-temperature protection shall provide a warning if the power module temperature is less than 5C below the over-temperature trip level.
Input terminals shall be provided for connecting a motor thermistor (PTC type) to the ASD’s protective monitoring circuitry. An input shall also be programmable to monitor an external relay or switch contact.
2.6 CONTROL INPUTS AND OUTPUTS
Minimum of seven (7) discrete inputs shall be provided.
A minimum of seven (7) of the inputs shall be independently programmable with function selections (run/stop, hand-off-auto, etc.).
Inputs shall be designed for use with either the ASD’s internal 24 VDC supply or a customer supplied external 24 VDC supply.
Minimum or three (3) form C relay contact outputs shall be provided
All outputs shall be independently programmable to activate with at least 30 function selections including;
Adjustable supervision limit indications based on programmed values of operating speed, speed reference, current, torque and PID feedback.
Relay contacts shall be rated to switch 2 Amps at 24 VDC or 115/230 VAC.
Minimum of two (2) analog inputs shall be provided:
Two (2) must be selectable for either a current or a voltage input.
Resolution of analog inputs must be at least 11bit total resolution
Inputs shall be independently programmable to provide signals including speed / frequency reference, torque reference or set point, PID set point and PID feedback / actual.
A differential input isolation amplifier shall be provided for each input.
Analog input signal processing functions shall include scaling adjustments, adjustable filtering and signal inversion.
If the input reference is lost, the ASD shall give the user the option of the following. The ASD shall be programmable to signal this condition via a keypad warning, relay output and/or over the serial communications bus.
Hold the ASD speed based on the last good reference received
Cause a warning to be issued, as selected by the user.
When inputs are used as speed references, reference signal processing shall include increase/decrease floating point control and control of speed and direction using a “joystick” reference signal. Two (2) analog inputs shall be programmable to form a reference by addition, subtraction, multiplication, minimum selection or maximum selection.
Minimum of two (2) 0 / 4-20 mA analog outputs shall be provided.
Outputs shall be independently programmable to provide signals proportional to output function selections including output speed, frequency, voltage, current and power.
Minimum of two (2) digital inputs/outputs shall be provided.
At least one (1) can be programmed as a frequency input. At least one (1) can be programmed as a frequency output.
Have a Safe Torque Off (STO) terminal integrated in the drive as a standard. The STO function will meet a Safety Integrity Level (SIL) 3 and a Performance Level (PL) e. This function will be certified by a third party approval agency e.g. TUV Nord.
2.7 SERIAL COMMUNICATIONS
The ASD shall be capable of communicating with other ASDs or controllers via a serial communications link. A variety of communications interface modules for the typical overriding control systems shall be available.
Interface modules shall be available for a wide selection of protocols including but not limited to:
Interface modules shall mount directly to the ASD control board or be connected via fiber optic cables to minimize interference and provide maximum throughput.
I/O shall be accessible through the serial communications adapter. Serial communication capabilities shall include, but not be limited to:
PID (proportional/integral/derivative) control adjustments
Accel/Decel time adjustments
The ASD shall have the capability of allowing the overriding controller to monitor feedback such as process variable feedback, output speed/frequency, current (in amps), % torque, power (kW), kilowatt hours (resettable), operating hours (resettable), relay outputs, and diagnostic warning and fault information.
A connection shall also be provided for personal computer interface. Software shall be available for ASD setup, diagnostic analysis, monitoring and control. The software shall provide real time graphical displays of ASD performance.
2.8 CONTROL FUNCTIONS AND ADJUSTMENTS
Output frequency shall be adjustable between 0Hz and 500Hz. Operation above motor nameplate shall require programming changes to prevent inadvertent high-speed operation.
Stop mode selections shall include coast to stop and ramp to stop.
The ASD shall be capable of controlling deceleration of a load without generating an overvoltage fault caused by excessive regenerated energy. Overvoltage control on deceleration shall extend the ramp time beyond the programmed value to keep the amount of regenerated energy below the point that causes overvoltage trip.
The ASD shall be capable of starting into a rotating motor with or without existing magnetic flux on the motor regardless of the motor direction. From the time the start signal is given to the ASD to the time the ASD has control of the motor shall not exceed two (2) seconds. Once the ASD has control of the motor it will than accelerate or decelerate the motor to the active reference speed without tripping or faulting or causing component damage to the ASD. The ASD shall also be capable of flux braking at start to stop a reverse spinning motor prior to ramp.
The ASD shall have the ability to automatically restart after an overcurrent, overvoltage, undervoltage, or loss of input signal protective trip. The number of restart attempts, trial time, and time between reset attempts shall be programmable.
Control functions shall include two (2) sets of acceleration and deceleration ramp time adjustments with linear and an s-curve ramp time selection.
Speed control functions shall include:
Adjustable min/max speed limits.
Selection of up to 7 preset speed settings for external speed control.
Three sets of critical speed lockout adjustments.
A built-in PID controller to control a process variable such as pressure, flow or fluid level.
Functions shall include energy optimization for optimizing efficiency and limit the audible noise produced by the motor by providing the optimum magnetic flux for any given speed / load operating point.
The ASD shall be capable of sensing a loss of load (broken belt / broken coupling) and signal the loss of load condition. The ASD shall be programmable to signal this condition via a keypad warning, relay output and/or over the serial communications bus. Relay output shall include programmable time delays that will allow for ASD acceleration from zero speed without signaling a false underload condition.
Three (3) programmable critical frequency lockout ranges shall be provided to prevent the ASD from operating the load continuously at an unstable speed.
The ASD shall offer software to select the ASDs action in the event of a loss of the primary speed reference.
Part 3 - OPTIONS
3.1 Wall mount ASDs from 0.75 to 350HP
UL Type 12 (IP55) enclosure.
ASD control panel mounting on separate enclosure or cabinet door
Dynamic braking chopper with 100% continuous duty internally mounted in ASD enclosure
Second Environment EMC / RFI filter and First environment EMC / RFI filter
Input and Output extension modules;
Analog input and output expansion
Digital input and output expansion
Speed and position feedback for TTL incremental encoder
Speed and position feedback for resolver interface
The ASD manufacturer shall provide adequate drawings and instruction material to facilitate installation of the ASD by qualified electrical and mechanical personnel employed by others.
Certified factory start-up shall be provided for each ASD by a factory authorized service center. A certified start-up form shall be filled out for each ASD with a copy provided to the owner, and a copy kept on file at the manufacturer.
The factory will extend the normal warranty for the ASD with a certified factory start-up.
4.3 PRODUCT SUPPORT
Factory trained application engineering and service personnel that are thoroughly familiar with the ASD products offered shall be locally available at both the specifying and installation locations.
A 24/365 technical support line shall be available on a toll-free-line.
Standard Warranty shall be 12 months from the date of start-up, not to exceed 18 months from the date of shipment. The warranty shall include all parts.
With a certified start-up (applicable in the USA and Canada only), warranty shall be 24 months from the date of start-up, not to exceed 30 months from the date of shipment. The warranty shall include all parts, labor, travel time, and expenses.
There shall be 24/365 support available on a toll-free-line.