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Allen-Bradley PowerFlex User Manual

Allen-Bradley PowerFlex
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Power Loss 2-109
Restart after Power Restoration
If a power loss causes the drive to coast and power recovers the drive will
return to powering the motor if it is in a “run permit” state. The drive is in a
“run permit” state if:
3 wire mode – it is not faulted and if all Enable and Not Stop inputs are
energized.
2 wire mode – it is not faulted and if all Enable, Not Stop, and Run inputs
are energized.
Power Loss Actions
The drive is designed to operate at a nominal bus voltage. When Vbus falls
below this nominal value by a significant amount, action can be taken to
preserve the bus energy and keep the drive logic alive as long as possible.
The drive will have three methods of dealing with low bus voltages:
“Coast” – Disable the transistors and allow the motor to coast.
“Inertia” Decelerate the motor at just the correct rate so that the energy
absorbed from the mechanical load balances the losses.
“Half Voltage” – Allow the drive to power the motor down to half bus
voltage.If Parameter #184 [Power Loss Mode] = “Coast”
Coast
This is the default mode of operation.
The drive determines a power loss has occurred if the bus voltage drops
below Vtrigger. If the drive is running the inverter output is disabled and the
motor coasts.
The power loss alarm in [Drive Alarm 1] is set and the power loss timer
starts.
The Alarm bit in [Drive Status 1] is set if the Power Loss bit in [Alarm
Config 1] is set.
The drive faults with a F003 – Power Loss Fault if the power loss timer
exceeds [Power Loss Time] and the Power Loss bit in [Fault Config 1] is
set.
The drive faults with a F004 – UnderVoltage fault if the bus voltage falls
below Vmin and the UnderVoltage bit in [Fault Config 1] is set.
The pre-charge relay opens if the bus voltage drops below Vopen and closes
if the bus voltage rises above Vclose
Power Loss
184 [Power Loss Mode]
Sets the reaction to aloss of input power.
Power loss is recognized when:
DC bus voltage is 73% of [DC Bus
Memory] and [Power Loss Mode] is
set to Coast.
DC bus voltage is 82% of [DC Bus
Memory] and [Power Loss Mode] is
set to Decel.
Default:
Options:
0
0
1
2
3
4
Coast
Coast
Decel
Continue
Coast Input
Decel Input
013
185

Table of Contents

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Allen-Bradley PowerFlex Specifications

General IconGeneral
CategoryDC Drives
ManufacturerAllen-Bradley
SeriesPowerFlex
Communication OptionsEtherNet/IP, DeviceNet, ControlNet
Protection FeaturesOvercurrent, Overvoltage, Undervoltage, Overtemperature, Short Circuit
Enclosure TypeNEMA 1, NEMA 12, NEMA 4/4X
Operating Temperature0°C to 40°C (32°F to 104°F)
Storage Temperature-40°C to 70°C (-40°F to 158°F)
Humidity5% to 95% (non-condensing)
AltitudeUp to 1000m (3280 ft) without derating

Summary

Specifications & Dimensions

PowerFlex 70/700 Specifications

Details specifications for PowerFlex 70 and 700 drives, including protection and certification.

Input/Output Ratings

Lists input/output ratings, environmental conditions, and electrical specifications for the drives.

Derating Guidelines

Provides guidelines for derating based on ambient temperature and load conditions.

Altitude and Efficiency Derating

Covers altitude derating factors and typical efficiency charts for PowerFlex 70 drives.

PowerFlex 70 Dimensions

Presents diagrams and tables for PowerFlex 70 frame dimensions and ratings.

PowerFlex 70 Bottom View Dimensions

Diagrams showing bottom view dimensions for PowerFlex 70 Frames A and B.

PowerFlex 70 Flange Mount Dimensions

Details overall dimensions, knockout, and cutout dimensions for flange mounting.

PowerFlex 700 Dimensions

Presents diagrams and tables for PowerFlex 700 frame dimensions and ratings.

Detailed Drive Operation

Accel Time

Sets the rate at which the drive ramps up its output frequency.

AC Supply Source Considerations

Details suitability for circuits up to 200,000 rms symmetrical amperes, 600V.

Alarms

Indicates situations affecting drive operation, classified as Type 1 or Type 2 alarms.

Application

Describes controlling a process with a 4-20 mA analog signal as speed reference.

Analog Inputs

Lists purposes for analog inputs: speed ref, trim, PI loop, limits.

Analog Outputs

Describes analog outputs used for annunciating drive conditions and values.

Auto / Manual

Allows overriding selected reference with HIM button or digital input.

Auto Restart (Reset/Run)

Automatically performs fault reset and start attempts without user intervention.

Bus Regulation

Manages DC bus voltage by adjusting output frequency to counter regeneration.

Cable, Control

Explains bus voltage regulator selection and set points in PowerFlex 70 and 700.

Cable, Motor Lengths

Discusses limitations due to Reflected Wave and Cable Charging.

Cable, Power

Discusses acceptable cable types and installation considerations for drive power.

CE Conformity

Details compliance with Low Voltage and EMC Directives using harmonized EN standards.

Copy Cat

Allows uploading/downloading parameter sets between HIM and drive for backup or transfer.

Current Limit

Describes six ways the drive protects itself from overcurrent and overload.

Datalinks

Mechanism for transferring data between drive and programmable controller via parameters.

DC Bus Voltage / Memory

Measures and stores instantaneous or nominal bus voltage for power-up and ride-through.

Decel Time

Sets rate of frequency decrease after stop command or speed change.

Digital Inputs

Configures digital inputs using [Digital Inx Sel] parameters for various functions.

Digital Outputs

Provides relay outputs for external annunciation of drive conditions.

Direction Control

Exclusive ownership function to command/control drive direction.

DPI

Enhancement to SCANport providing more functions and better performance.

Drive Overload

Functions to prevent drive abuse and maintain performance by managing thermal ratings.

Economizer

Energy saving function adjusting output voltage based on load for optimized efficiency.

Fan Curve

Relates frequency and voltage, generating voltage as a function of stator frequency squared.

Faults

Events or conditions constituting user notification, some user-configurable.

Flying Start

Starts into a rotating motor quickly, resuming normal operation with minimal impact.

Fuses and Circuit Breakers

Provides drive ratings and recommended AC line input fuse/circuit breaker information.

Grounding, General

Ensures safety ground connection to system ground and checks integrity.

HIM Operations

Covers language selection, password management, and user display configuration.

Input Devices

Sections on Contactors, Circuit Breakers/Fuses, and Filters.

Input Modes

Allows full configuration of digital I/O for 2-wire or 3-wire control.

Input Power Conditioning

Rules for considering line reactors or isolation transformers for AC line connection.

Masks

Parameters controlling command access for adapters via bits.

Motor Nameplate

Parameters for entering motor nameplate data like Volts, FLA, Hz, RPM, Power.

Motor Overload

Uses IT algorithm to model motor temperature for Class 10 protection.

Motor Start/Stop Precautions

Precautions regarding contactors and solid-state components for start/stop.

Output Current

Displays total output current as vector sum of torque and flux components.

Output Frequency

Displays actual output frequency, sum of commanded frequency and regulators.

Overspeed Limit

Allows operation at max speed, provides overspeed band for speed regulator.

Owners

Parameter indicating which adapter has ownership of specific drive functions.

Parameter Access Level

Restricts parameter viewability on HIM to commonly adjusted sets.

Power Loss

Handles drive output interruptions due to momentary power outages.

Preset Frequency

Stores discrete frequency values for speed or PI reference, accessed via digital inputs or DPI.

Process PI Loop

Provides closed-loop process control with proportional and integral action.

Reflected Wave

Discusses PWM inverter pulses and resulting over-voltage transients at the motor.

Reset Meters

Notes that this section is under construction.

S Curve

Controls 'jerk' component of acceleration/deceleration for smoother transitions.

Scaling Blocks

Notes that this section is under construction.

Shear Pin Fault

Faults drive if output current exceeds programmed current limit.

Skip Bands

Provides three skip bands to ramp through but not run within.

Sleep Mode

Starts (wakes) drive when analog signal meets Wake Level, stops when it meets Sleep Level.

Speed Control Speed Mode Speed Regulation

Adjusts operating conditions to compensate for motor speed losses.

Start Inhibits

Indicates inverted state of start permissive conditions, inhibiting starting if not met.

Start Permissives

Conditions required to permit drive start; drive is considered ready when met.

Start-Up

Offers routines to help user commission drive easily and quickly.

Stop Modes

Describes modes for stopping the drive: Coast, Dynamic Braking, Brake to Stop.

Test Points

Selects function value for display; displays present value of selected function.

Torque Performance Modes

Defines relationship between frequency and voltage for torque control.

Troubleshooting

Section on troubleshooting drive issues.

Unbalanced or Ungrounded Distribution Systems

Drive designed for symmetrical three-phase supplies; recommends isolation transformer for high phase-to-ground voltage.

User Sets

Allows storing up to 3 parameter sets for backup, switching, or other needs.

Voltage class

Identifies general input voltage to the drive; can be reprogrammed by resetting defaults.

Watts Loss

Lists watts loss data for PowerFlex drives at full load, speed, and 4kHz PWM.

Appendix A Dynamic Brake Selection Guide

What This Guide Contains

Information on determining dynamic braking needs and selecting resistor ratings.

How Dynamic Braking Works

Explains motoring, regeneration, and how AC PWM drives convert power.

Dynamic Brake Components

Describes the dynamic braking circuitry, its components, and their function.

How to Determine Dynamic Brake Requirements

Information needed for estimating dynamic brake resistor value based on operation.

Step 2 Total Inertia

Calculates total inertia reflected to the motor shaft using motor and load inertia.

Step 3 Peak Braking Power

Calculates peak braking power using inertia, speed, and deceleration time.

Step 4 Minimum Power Requirements for the Dynamic Brake Resistors

Calculates average duty cycle and average power regenerated over a cycle.

Step 5 Percent Average Load of the Internal Dynamic Brake Resistor

Calculates average load in percent of dynamic brake resistor capacity.

Step 6 Percent Peak Load of the Internal Dynamic Brake Resistor

Calculates peak load in percent of dynamic brake resistor capacity.

Example Calculation

Walkthrough of calculations for choosing a dynamic brake resistor.

Section 3

Determines if internal dynamic brake resistor meets application requirements using calculated values.

Section 4

Guidance on selecting an external dynamic brake resistor for your application.

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