Danfoss VLT AutomationDrive FC 300 Guide

Contents
How to Read this Design Guide
5
How to Read this Design Guide 5
Approvals 5
Symbols 6
Abbreviations 6
Definitions 7
Introduction to FC 300
13
Safety Precautions 13
Safety Precautions 13
Disposal Instruction 14
Software Version 15
Control Principle 19
FC 300 Controls 19
FC 301 vs. FC 302 Control Principle 19
Control Structure in VVC
plus
20
Control Structure in Flux Sensorless (FC 302 only) 21
Control Structure in Flux with Motor Feedback 21
Internal Current Control in VVC
plus
Mode 22
Local (Hand On) and Remote (Auto On) Control 22
Reference Handling 24
Scaling of References and Feedback 25
Dead Band Around Zero 27
Speed PID Control 31
The following parameters are relevant for the Speed Control 31
Process PID Control 33
Ziegler Nichols Tuning Method 37
Motor cables to comply with EMC regulations 39
EMC Immunity 40
Earth Leakage Current 42
Selection of Brake Resistor 42
Mechanical Brakecontrol 44
Hoist Mechanical Brake 45
Safe Stop of FC 300 48
Safe Stop Installation (FC 302 and FC 301 - A1 enclosure only) 49
Safe Stop Commissioning Test 50
FC 300 Selection
53
Electrical Data 53
General Specifications 59
Efficiency 64
Acoustic Noise 64
Peak Voltage on Motor 65
Purpose of derating 66
Automatic adaptations to ensure performance 69
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How to Order
71
Drive Configurator 71
Ordering Form Type Code 71
Ordering Numbers 73
How to Install
79
Mechanical Dimension 79
Mechanical Installation 81
Accessory Bag 81
Electrical Installation 84
Removal of Knockouts for Extra Cables 84
Connection to Mains and Earthing 85
Motor Connection 87
Fuses 89
Access to Control Terminals 91
Control Terminals 91
Electrical Installation, Control Terminals 92
Basic Wiring Example 92
Electrical Installation, Control Cables 93
Motor Cables 95
Switches S201, S202, and S801 96
Final Set-Up and Test 97
Additional Connections 99
Relay Connection 100
Relay Output 101
Parallel Connection of Motors 101
Motor Thermal Protection 102
How to Connect a PC to the FC 300 103
The FC 300 Software Dialog 103
Residual Current Device 108
Application Examples
109
Start/Stop 109
Pulse Start/Stop 109
Potentiometer Reference 110
Encoder Connection 110
Encoder Direction 110
Closed Loop Drive System 111
Programming of Torque Limit and Stop 111
Smart Logic Control Programming 112
Options and Accessories
115
Options and Accessories 115
Mounting of Option Modules in Slot B 115
General Purpose Input Output Module MCB 101 115
Encoder Option MCB 102 117
Resolver Option MCB 103 119
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Relay Option MCB 105 121
24 V Back-Up Option MCB 107 (Option D) 124
IP 21/IP 4X/ TYPE 1 Enclosure Kit 125
Sine-wave Filters 126
RS-485 Installation and Set-up
127
RS-485 Installation and Set-up 127
FC Protocol Overview 130
Network Configuration 130
FC Protocol Message Framing Structure - FC 300 131
Examples 136
Danfoss FC Control Profile 136
Troubleshooting
149
Status messages - FC 300 DG 149
Warnings/Alarm Messages 149
Index
158
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How to Read this Design Guide
How to Read this Design Guide
This Design Guide will introduce all aspects of your FC 300.
Available literature for FC 300
-The VLT
®
AutomationDrive FC 300 Operating Instructions MG.33.AX.YY provide the neccessary
information for getting the drive up and running.
-The VLT
®
AutomationDrive FC 300 Design Guide MG.33.BX.YY entails all technical information
about the drive and customer design and applications.
-The VLT
®
AutomationDrive FC 300 Programming Guide MG.33.MX.YY provides information on
how to programme and includes complete parameter descriptions.
-The VLT
®
AutomationDrive FC 300 Profibus Operating Instructions MG.33.CX.YY provide the in-
formation required for controlling, monitoring and programming the drive via a Profibus fieldbus.
-The VLT
®
AutomationDrive FC 300 DeviceNet Operating Instructions MG.33.DX.YY provide the
information required for controlling, monitoring and programming the drive via a DeviceNet field-
bus.
X = Revision number
YY = Language code
Danfoss Drives technical literature is also available online at www.danfoss.com/BusinessAreas/Drives-
Solutions/Documentations/Technical+Documentation.
Approvals
FC 300 Design Guide
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Symbols
Symbols used in this guide.
NB!
Indicates something to be noted by the reader.
Indicates a general warning.
Indicates a high-voltage warning.
*Indicates default setting
Abbreviations
Alternating current AC
American wire gauge AWG
Ampere/AMP A
Automatic Motor Adaptation AMA
Current limit ILIM
Degrees Celcius °C
Direct current DC
Drive Dependent D-TYPE
Electro Magnetic Compatibility EMC
Electronic Thermal Relay ETR
Frequency Converter FC
Gram g
Hertz Hz
Kilohertz kHz
Local Control Panel LCP
Meter m
Milli Henry Inductance mH
Milliampere mA
Millisecond ms
Minute min
Motion Control Tool MCT
Nanofarad nF
Newton Meters Nm
Nominal motor current IM,N
Nominal motor frequency fM,N
Nominal motor power PM,N
Nominal motor voltage UM,N
Parameter par.
Protective Extra Low Voltage PELV
Printed Circuit Board PCB
Rated Inverter Output Current IINV
Revolutions Per Minute RPM
Second s
Torque limit TLIM
Volts V
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Definitions
Drive:
D-TYPE
Size and type of the connected drive (dependencies).
I
VLT,MAX
The maximum output current.
I
VLT,N
The rated output current supplied by the frequency converter.
U
VLT, MAX
The maximum output voltage.
Input:
Control command
You can start and stop the connected motor by
means of LCP and the digital inputs.
Functions are divided into two groups.
Functions in group 1 have higher priority than
functions in group 2.
Group 1 Reset, Coasting stop, Reset and
Coasting stop, Quick-stop, DC
braking, Stop and the "Off" key.
Group 2 Start, Pulse start, Reversing,
Start reversing, Jog and Freeze
output
Motor:
f
JOG
The motor frequency when the jog function is activated (via digital terminals).
f
M
The motor frequency.
f
MAX
The maximum motor frequency.
f
MIN
The minimum motor frequency.
f
M,N
The rated motor frequency (nameplate data).
I
M
The motor current.
I
M,N
The rated motor current (nameplate data).
M-TYPE
Size and type of the connected motor (dependencies).
n
M,N
The rated motor speed (nameplate data).
P
M,N
The rated motor power (nameplate data).
T
M,N
The rated torque (motor).
U
M
The instantaneous motor voltage.
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U
M,N
The rated motor voltage (nameplate data).
Break-away torque

VLT
The efficiency of the frequency converter is defined as the ratio between the power output and the power
input.
Start-disable command
A stop command belonging to the group 1 control commands - see this group.
Stop command
See Control commands.
References:
Analog Reference
A signal transmitted to the analog inputs 53 or 54, can be voltage or current.
Binary Reference
A signal transmitted to the serial communication port.
Preset Reference
A defined preset reference to be set from -100% to +100% of the reference range. Selection of eight
preset references via the digital terminals.
Pulse Reference
A pulse frequency signal transmitted to the digital inputs (terminal 29 or 33).
Ref
MAX
Determines the relationship between the reference input at 100% full scale value (typically 10 V, 20mA)
and the resulting reference. The maximum reference value set in par. 3-03.
Ref
MIN
Determines the relationship between the reference input at 0% value (typically 0V, 0mA, 4mA) and the
resulting reference. The minimum reference value set in par. 3-02.
Miscellaneous:
Analog Inputs
The analog inputs are used for controlling various functions of the frequency converter.
There are two types of analog inputs:
Current input, 0-20 mA and 4-20 mA
Voltage input, 0-10 V DC (FC 301)
Voltage input, -10 - +10 V DC (FC 302).
Analog Outputs
The analog outputs can supply a signal of 0-20 mA, 4-20 mA, or a digital signal.
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Automatic Motor Adaptation, AMA
AMA algorithm determines the electrical parameters for the connected motor at standstill.
Brake Resistor
The brake resistor is a module capable of absorbing the brake power generated in regenerative braking.
This regenerative braking power increases the intermediate circuit voltage and a brake chopper ensures
that the power is transmitted to the brake resistor.
CT Characteristics
Constant torque characteristics used for all applications such as conveyor belts, displacement pumps and
cranes.
Digital Inputs
The digital inputs can be used for controlling various functions of the frequency converter.
Digital Outputs
The drive features two Solid State outputs that can supply a 24 V DC (max. 40 mA) signal.
DSP
Digital Signal Processor.
ETR
Electronic Thermal Relay is a thermal load calculation based on present load and time. Its purpose is to
estimate the motor temperature.
Hiperface
®
Hiperface
®
is a registered trademark by Stegmann.
Initialising
If initialising is carried out (par. 14-22), the frequency converter returns to the default setting.
Intermittent Duty C ycle
An intermittent duty rating refers to a sequence of duty cycles. Each cycle consists of an on-load and an
off-load period. The operation can be either periodic duty or non-periodic duty.
LCP
The Local Control Panel (LCP) makes up a complete interface for control and programming of the FC 300
Series. The control panel is detachable and can be installed up to 3 metres from the frequency converter,
i.e. in a front panel by means of the installation kit option.
lsb
Least significant bit.
msb
Most significant bit.
MCM
Short for Mille Circular Mil, an American measuring unit for cable cross-section. 1 MCM = 0.5067 mm
2
.
On-line/Off-line Parameters
Changes to on-line parameters are activated immediately after the data value is changed. Changes to
off-line parameters are not activated until you enter [OK] on the LCP.
Process PID
The PID regulator maintains the desired speed, pressure, temperature, etc. by adjusting the output fre-
quency to match the varying load.
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Pulse Input/Incremental Encoder
An external, digital pulse transmitter used for feeding back information on motor speed. The encoder is
used in applications where great accuracy in speed control is required.
RCD
Residual Current Device.
Set-up
You can save parameter settings in four Set-ups. Change between the four parameter Set-ups and edit
one Set-up, while another Set-up is active.
SFAVM
Switching pattern called Stator Flux oriented Asynchronous Vector Modulation (par. 14-00).
Slip Compensation
The frequency converter compensates for the motor slip by giving the frequency a supplement that fol-
lows the measured motor load keeping the motor speed almost constant..
Smart Logic Control (SLC)
The SLC is a sequence of user defined actions executed when the associated user defined events are
evaluated as true by the SLC. (Parameter group 13-xx).
FC Standard Bus
Includes RS 485 bus with FC protocol or MC protocol. See parameter 8-30.
Thermistor:
A temperature-dependent resistor placed where the temperature is to be monitored (frequency converter
or motor).
Trip
A state entered in fault situations, e.g. if the frequency converter is subject to an over-temperature or
when the frequency converter is protecting the motor, process or mechanism. Restart is prevented until
the cause of the fault has disappeared and the trip state is cancelled by activating reset or, in some cases,
by being programmed to reset automatically. Trip may not be used for personal safety.
Trip Locked
A state entered in fault situations when the frequency converter is protecting itself and requiring physical
intervention, e.g. if the frequency converter is subject to a short circuit on the output. A locked trip can
only be cancelled by cutting off mains, removing the cause of the fault, and reconnecting the frequency
converter. Restart is prevented until the trip state is cancelled by activating reset or, in some cases, by
being programmed to reset automatically. Trip may not be used for personal safety.
VT Characteristics
Variable torque characteristics used for pumps and fans.
VVC
plus
If compared with standard voltage/frequency ratio control, Voltage Vector Control (VVC
plus
) improves the
dynamics and the stability, both when the speed reference is changed and in relation to the load torque.
60° AVM
Switching pattern called 60°Asynchronous Vector Modulation (par. 14-00).
Power Factor
The power factor is the relation between I
1
and
I
RMS
.
Power factor =3
xU xI 1 xcos ϕ
3 xU xI
RMS
The power factor for 3-phase control:
=
I 1 xcos ϕ1
I
RMS
=
I
1
I
RMS
since cos ϕ1=1
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The power factor indicates to which extent the
frequency converter imposes a load on the mains
supply.
The lower the power factor, the higher the I
RMS
for
the same kW performance.
I
RMS
= I
1
2
+ I
5
2
+ I
7
2
+.. + I
n
2
In addition, a high power factor indicates that the different harmonic currents are low.
The FC 300 frequency converters' built-in DC coils produce a high power factor, which minimizes the
imposed load on the mains supply.
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FC 300 Design Guide
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Introduction to FC 300
Safety Precautions
The voltage of the frequency converter is dangerous whenever connected to mains. Incorrect
installation of the motor, frequency converter or fieldbus may cause damage to the equip-
ment, serious personal injury or death. Consequently, the instructions in this manual, as well
as national and local rules and safety regulations, must be complied with.
Safety Regulations
1. The frequency converter must be disconnected from mains if repair work is to be carried out.
Check that the mains supply has been disconnected and that the necessary time has passed
before removing motor and mains plugs.
2. The [STOP/RESET] key on the control panel of the frequency converter does not disconnect the
equipment from mains and is thus not to be used as a safety switch.
3. Correct protective earthing of the equipment must be established, the user must be protected
against supply voltage, and the motor must be protected against overload in accordance with
applicable national and local regulations.
4. The earth leakage currents are higher than 3.5 mA.
5. Protection against motor overload is not included in the factory setting. If this function is desired,
set par. 1-90 to data value ETR trip or data value ETR warning.
NB!
The function is initialised at 1.16 x rated motor current and rated motor frequency. For the
North American market: The ETR functions provide class 20 motor overload protection in ac-
cordance with NEC.
6. Do not remove the plugs for the motor and mains supply while the frequency converter is con-
nected to mains. Check that the mains supply has been disconnected and that the necessary time
has passed before removing motor and mains plugs.
7. Please note that the frequency converter has more voltage inputs than L1, L2 and L3, when load
sharing (linking of DC intermediate circuit) and external 24 V DC have been installed. Check that
all voltage inputs have been disconnected and that the necessary time has passed before com-
mencing repair work.
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Warning against Unintended Start
1. The motor can be brought to a stop by means of digital commands, bus commands, references
or a local stop, while the frequency converter is connected to mains. If personal safety consid-
erations make it necessary to ensure that no unintended start occurs, these stop functions are
not sufficient.
2. While parameters are being changed, the motor may start. Consequently, the stop key [STOP/
RESET] must always be activated; following which data can be modified.
3. A motor that has been stopped may start if faults occur in the electronics of the frequency con-
verter, or if a temporary overload or a fault in the supply mains or the motor connection ceases.
Touching the electrical parts may be fatal - even after the equipment has been disconnected
from mains.
Also make sure that other voltage inputs have been disconnected, such as external 24 V DC, load sharing
(linkage of DC intermediate circuit), as well as the motor connection for kinetic back up. Refer to FC 300
Operating Instructions (MG.33.A8.xx) for further safety guidelines.
Disposal Instruction
Equipment containing electrical components may not be disposed of togeth-
er with domestic waste.
It must be separately collected with Electrical and Electronic waste accord-
ing to local and currently valid legislation.
Caution
The FC 300 AutomationDrive DC link capacitors remain charged after power has been disconnected.
To avoid electrical shock hazard, disconnect the FC 300 from the mains before carrying out mainte-
nance. Before doing service on the frequency converter wait at least the amount of time indicated
below:
FC 300: 0.25 – 7.5 kW 4 minutes
FC 300: 11 – 22 kW 15 minutes
FC 300: 30 - 75 kW 15 minutes
FC 300 Design Guide
Introduction to FC 300
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FC 300
Design Guide
Software version: 4.0x
This Design Guide can be used for all FC 300 frequency converters with software version 4.0x.
The software version number can be seen from parameter 15-43.
FC 300 Design Guide
Introduction to FC 300
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CE Conformity and Labelling
What is CE Conformity and Labelling?
The purpose of CE labelling is to avoid technical trade obstacles within EFTA and the EU. The EU has
introduced the CE label as a simple way of showing whether a product complies with the relevant EU
directives. The CE label says nothing about the specifications or quality of the product. Frequency con-
verters are regulated by three EU directives:
The machinery directive (98/37/EEC)
All machines with critical moving parts are covered by the machinery directive of January 1, 1995. Since
a frequency converter is largely electrical, it does not fall under the machinery directive. However, if a
frequency converter is supplied for use in a machine, we provide information on safety aspects relating
to the frequency converter. We do this by means of a manufacturer's declaration.
The low-voltage directive (73/23/EEC)
Frequency converters must be CE labelled in accordance with the low-voltage directive of January 1,
1997. The directive applies to all electrical equipment and appliances used in the 50 - 1000 V AC and the
75 - 1500 V DC voltage ranges. Danfoss CE-labels in accordance with the directive and issues a decla-
ration of conformity upon request.
The EMC directive (89/336/EEC)
EMC is short for electromagnetic compatibility. The presence of electromagnetic compatibility means that
the mutual interference between different components/appliances does not affect the way the appliances
work.
The EMC directive came into effect January 1, 1996. Danfoss CE-labels in accordance with the directive
and issues a declaration of conformity upon request. To carry out EMC-correct installation, see the in-
structions in this Design Guide. In addition, we specify which standards our products comply with. We
offer the filters presented in the specifications and provide other types of assistance to ensure the opti-
mum EMC result.
The frequency converter is most often used by professionals of the trade as a complex component forming
part of a larger appliance, system or installation. It must be noted that the responsibility for the final EMC
properties of the appliance, system or installation rests with the installer.
What Is Covered
The EU "Guidelines on the Application of Council Directive 89/336/EEC" outline three typical situations of
using a frequency converter. See below for EMC coverage and CE labelling.
1. The frequency converter is sold directly to the end-consumer. The frequency converter is for
example sold to a DIY market. The end-consumer is a layman. He installs the frequency converter
himself for use with a hobby machine, a kitchen appliance, etc. For such applications, the fre-
quency converter must be CE labelled in accordance with the EMC directive.
2. The frequency converter is sold for installation in a plant. The plant is built up by professionals
of the trade. It could be a production plant or a heating/ventilation plant designed and installed
by professionals of the trade. Neither the frequency converter nor the finished plant has to be CE
labelled under the EMC directive. However, the unit must comply with the basic EMC require-
ments of the directive. This is ensured by using components, appliances, and systems that are
CE labelled under the EMC directive.
3. The frequency converter is sold as part of a complete system. The system is being marketed as
complete and could e.g. be an air-conditioning system. The complete system must be CE labelled
in accordance with the EMC directive. The manufacturer can ensure CE labelling under the EMC
directive either by using CE labelled components or by testing the EMC of the system. If he
chooses to use only CE labelled components, he does not have to test the entire system.
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Introduction to FC 300
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Danfoss VLT Frequency Converter and CE
Labelling
CE labelling is a positive feature when used for its original purpose, i.e. to facilitate trade within the EU
and EFTA.
However, CE labelling may cover many different specifications. Thus, you have to check what a given CE
label specifically covers.
The covered specifications can be very different and a CE label may therefore give the installer a false
feeling of security when using a frequency converter as a component in a system or an appliance.
Danfoss CE labels the frequency converters in accordance with the low-voltage directive. This means that
if the frequency converter is installed correctly, we guarantee compliance with the low-voltage directive.
Danfoss issues a declaration of conformity that confirms our CE labelling in accordance with the low-
voltage directive.
The CE label also applies to the EMC directive provided that the instructions for EMC-correct installation
and filtering are followed. On this basis, a declaration of conformity in accordance with the EMC directive
is issued.
The Design Guide offers detailed instructions for installation to ensure EMC-correct installation. Further-
more, Danfoss specifies which our different products comply with.
Danfoss gladly provides other types of assistance that can help you obtain the best EMC result.
Compliance with EMC Directive 89/336/EEC
As mentioned, the frequency converter is mostly used by professionals of the trade as a complex com-
ponent forming part of a larger appliance, system, or installation. It must be noted that the responsibility
for the final EMC properties of the appliance, system or installation rests with the installer. As an aid to
the installer, Danfoss has prepared EMC installation guidelines for the Power Drive system. The standards
and test levels stated for Power Drive systems are complied with, provided that the EMC-correct instruc-
tions for installation are followed, see section Electrical Installation.
The frequency converter has been designed to meet the IEC/EN 60068-2-3 standard, EN 50178 pkt.
9.4.2.2 at 50°C.
A frequency converter contains a large number of mechanical and electronic components. All are to some
extent vulnerable to environmental effects.
The frequency converter should not be installed in environments with airborne liquids, parti-
cles, or gases capable of affecting and damaging the electronic components. Failure to take
the necessary protective measures increases the risk of stoppages, thus reducing the life of
the frequency converter.
Liquids can be carried through the air and condense in the frequency converter and may cause corrosion
of components and metal parts. Steam, oil, and salt water may cause corrosion of components and metal
parts. In such environments, use equipment with enclosure rating IP 55. As an extra protection, coated
printet circuit boards can be orded as an option.
Airborne Particles such as dust may cause mechanical, electrical, or thermal failure in the frequency con-
verter. A typical indicator of excessive levels of airborne particles is dust particles around the frequency
converter fan. In very dusty environments, use equipment with enclosure rating IP 55 or a cabinet for IP
00/IP 20/TYPE 1 equipment.
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In environments with high temperatures and humidity, corrosive gases such as sulphur, nitrogen, and
chlorine compounds will cause chemical processes on the frequency converter components.
Such chemical reactions will rapidly affect and damage the electronic components. In such environments,
mount the equipment in a cabinet with fresh air ventilation, keeping aggressive gases away from the
frequency converter.
An extra protection in such areas is a coating of the printed circuit boards, which can be ordered as an
option.
NB!
Mounting frequency converters in aggressive environments increases the risk of stoppages
and considerably reduces the life of the converter.
Before installing the frequency converter, check the ambient air for liquids, particles, and gases. This is
done by observing existing installations in this environment. Typical indicators of harmful airborne liquids
are water or oil on metal parts, or corrosion of metal parts.
Excessive dust particle levels are often found on installation cabinets and existing electrical installations.
One indicator of aggressive airborne gases is blackening of copper rails and cable ends on existing in-
stallations.
The frequency converter has been tested according to a procedure based on the shown standards:
The frequency converter complies with requirements that exist for units mounted on the walls and floors
of production premises, as well as in panels bolted to walls or floors.
IEC/EN 60068-2-6: Vibration (sinusoidal) - 1970
IEC/EN 60068-2-64: Vibration, broad-band random
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Introduction to FC 300
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Control Principle
A frequency converter rectifies AC voltage from mains into DC voltage, after which this DC voltage is
converted into a AC current with a variable amplitude and frequency.
The motor is supplied with variable voltage / current and frequency, which enables infinitely variable
speed control of three-phased, standard AC motors and permanent magnet synchronous motors.
FC 300 Controls
The frequency converter is capable of controlling either the speed or the torque on the motor shaft. Set-
ting par. 1-00 determines the type of control.
Speed control:
There are two types of speed control:
• Speed open loop control which does not require any feedback (sensorless).
• Speed closed loop control in the form of a PID control that requires a speed feedback to an input.
A properly optimised speed closed loop control will have higher accuracy than a speed open loop
control.
Selects which input to use as speed PID feedback in par. 7-00.
Torque control (FC 302 only):
Torque control is part of the motor control and correct settings of motor parameters are very important.
The accuracy and settling time of the torque control are determined from Flux with motor feedback (par.
1-01 Motor Control Principle).
• Flux with encoder feedback offers superior performance in all four quadrants and at all motor
speeds.
Speed / torque reference:
The reference to these controls can either be a single refrence or be the sum of various references in-
cluding relatively scaled references. The handling of references is explained in detail later in this section.
FC 301 vs. FC 302 Control Principle
FC 301 is a general purpose frequency converter for variable speed applications. The control principle is
based on Voltage Vector Control (VVC
plus
).
FC 301 can handle asynchronous motors only.
The current sensing principle in FC 301 is based on current measurement in the DC link or motor phase.
The ground fault protection on the motor side is solved by a de-saturation circuit in the IGBTs connected
to the control board.
Short circuit behaviour on FC 301 depends on the current transducer in the positive DC link and the
desaturation protection with feedback from the 3 lower IGBT's and the brake.
FC 300 Design Guide
Introduction to FC 300
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FC 302 is a high performance frequency converter for demanding applications. The frequency converter
can handle various kinds of motor control principles such as U/f special motor mode, VVC
plus
or Flux Vector
motor control.
FC 302 is able to handle Permanent Magnet Synchronous Motors (Brushless servo motors) as well as
normal squirrel cage asynchronous motors.
Short circuit behaviour on FC 302 depends on the 3 current transducers in the motor phases and the
desaturation protection with feedback from the brake.
Control Structure in VVC
plus
Control structure in VVC
plus
open loop and closed loop configurations:
In the configuration shown in the illustration above, par. 1-01 Motor Control Principle is set to “VVC
plus
[1]” and par. 1-00 is set to “Speed open loop [0]”. The resulting reference from the reference handling
system is received and fed through the ramp limitation and speed limitation before being sent to the
motor control. The output of the motor control is then limited by the maximum frequency limit.
If par. 1-00 is set to “Speed closed loop [1]” the resulting reference will be passed from the ramp limi-
tation and speed limitation into a speed PID control. The Speed PID control parameters are located in the
par. group 7-0*. The resulting reference from the Speed PID control is sent to the motor control limited
by the frequency limit.
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