6.0–10 kW (8–15 hp): Version 2.0
18–30 kW (25–40 hp): Version 61.20
Description
Conformity mark
EU/EC Declaration of Conformity (EC/CE - European Conformity/Conformité Européenne)
Low Voltage Directive/Electromagnetic compatibility (EMC)/Restriction of Hazardous Substances
(RoHS)
Countries of use: Europe
ACMA Declaration of Conformity (RCM - Regulatory Compliance Mark)
Australian Communications Media Authority (ACMA)
Low Voltage Directive/Electromagnetic compatibility (EMC)
Countries of use: Australia and New Zealand
VLT® Compressor Drive CDS 803
Design Guide
Introduction
1 Introduction
1.1 Purpose of this Design Guide
This Design Guide is intended for qualified personnel, such as:
•
Project and systems engineers.
•
Design consultants.
•
Application and product specialists.
The Design Guide provides technical information to understand the capabilities of the VLT® Compressor Drive CDS 803 for integration into motor control and monitoring systems. Its purpose is to provide design considerations and planning data for integration of
the drive into a system. It caters for selection of drives and options for a diversity of applications and installations. Reviewing the
detailed product information in the design stage enables developing a well-conceived system with optimal functionality and efficiency.
This manual is targeted at a worldwide audience. Therefore, wherever occurring, both SI and imperial units are shown.
VLT® is a registered trademark for Danfoss A/S.
1.2 Additional Resources
1.2.1 Supplementary Documentation
Various resources are available to understand advanced drive operation, programming, and directives compliance.
•
The Programming Guide provides information on how to program and includes complete parameter descriptions.
•
The Operating Guide provides detailed information about installation and commissioning of the drive.
See www.danfoss.com for supplementary documentation.
1.2.2 VLT® Motion Control Tool MCT 10 Software Support
Download the software from the Service and Support download page on www.danfoss.com.
During the installation process of the software, enter CD-key 34544400 to activate the CDS 803 functionality. An activation key is not
required for using the CDS 803 functionality.
The latest software does not always contain the latest updates for the drive. Contact the local sales office for the latest drive updates
(in the form of *.upd files), or download the drive updates from the Service and Support download page on www.danfoss.com.
1.3 Manual and Software Version
This manual is regularly reviewed and updated. All suggestions for improvement are welcome.
Indicates a hazardous situation which, if not avoided, will result in death or serious injury.
W A R N I N G
Indicates a hazardous situation which, if not avoided, could result in death or serious injury.
C A U T I O N
Indicates a hazardous situation which, if not avoided, could result in minor or moderate injury.
N O T I C E
Indicates information considered important, but not hazard-related (for example, messages relating to property damage).
Safety
2.2 Qualified Personnel
To allow trouble-free and safe operation of the unit, only qualified personnel with proven skills are allowed to transport, store, assemble, install, program, commission, maintain, and decommission this equipment.
Persons with proven skills:
•
Are qualified electrical engineers, or persons who have received training from qualified electrical engineers and are suitably
experienced to operate devices, systems, plant, and machinery in accordance with pertinent laws and regulations.
•
Are familiar with the basic regulations concerning health and safety/accident prevention.
•
Have read and understood the safety guidelines given in all manuals provided with the unit, especially the instructions given in
the Operating Guide.
•
Have good knowledge of the generic and specialist standards applicable to the specific application.
2.3 Safety Precautions
W A R N I N G
HAZARDOUS VOLTAGE
AC drives contain hazardous voltage when connected to the AC mains or connected on the DC terminals. Failure to perform
installation, start-up, and maintenance by skilled personnel can result in death or serious injury.
Only skilled personnel must perform installation, start-up, and maintenance.
-
W A R N I N G
UNINTENDED START
When the drive is connected to AC mains, DC supply, or load sharing, the motor may start at any time. Unintended start during
programming, service, or repair work can result in death, serious injury, or property damage. Start the motor with an external
switch, a fieldbus command, an input reference signal from the local control panel (LCP), via remote operation using MCT 10
software, or after a cleared fault condition.
Disconnect the drive from the mains.
-
Press [Off/Reset] on the LCP before programming parameters.
-
Ensure that the drive is fully wired and assembled when it is connected to AC mains, DC supply, or load sharing.
Danfoss offers CDS drives in different-sized enclosures with power ratings from 6.0–30 kW (8.0–40 hp). Common for all drives are
the following:
•
I/Os
-
4 digital inputs (PNP or NPN)
-
2 digital outputs
-
2 analog inputs (voltage or current)
-
2 analog outputs
-
2 relay outputs
•
RS485 serial communication
-
Danfoss FC protocol and VLT® Motion Control Tool MCT 10 support
-
Modbus RTU
The drive is a free-standing, wall-mountable, or cabinet-mountable drive available in different ratings to fit various applications. The
complete overview is listed in Table 3.
Illustration 1: VLT® Compressor Drive CDS 803 Family
Table 3: Overview of VLT® Compressor Drive CDS 803 Family
Product Overview
1
All CDS 803 drives can be upgraded to IP21/NEMA Type 1 with an IP21/NEMA Type 1 Conversion Kit.
3.2 VLT® Compressor Drive CDS 803 Features
Various application functions are programmed in the drive for enhanced system performance. The functions require minimum programming or setup. For activation of the functions, refer to the VLT® Compressor Drive CDS 803 Programming Guide listed in 1.2
Additional Resources.
3.2.1 Compressor Features
The VLT® Compressor Drive CDS 803 offers various specialized functions for use in combination with compressor systems.
3.2.1.1 Secure Start-up
To ensure that the compressor ramps fast to the defined start speed, the VLT® Compressor Drive CDS 803 always runs a start-up
sequence. The compressor runs at the start speed for a defined fixed time.
•
If a locked rotor or flooded compressor occurs, it is detected during start-up.
•
If the drive fails to start the compressor, it trips on Alarm 18, Start failed.
To avoid a malfunction inside the compressor due to missing or low lubrication the VLT® Compressor Drive CDS 803 protects the
compressor if the speed drops below the minimum speed detection limit for too long.
•
In case of excessive low speed the drive issues Alarm 49, Speed limit.
The VLT® Compressor Drive CDS 803 includes a compressor short-cycling protection that prevents mechanical wear to the compressor and reduces the risk of oil shortage caused by starting and stopping too often. The short-cycle protection consists of 2 timers:
•
The interval between starts ensures that a new start first becomes active when the start time has expired.
•
The minimum run time ensures that the compressor always runs for a defined minimum time before stopping the compressor.
•
Warning 96, Start Delay is shown in the display if there is a start signal and the INTERVAL BETWEEN STARTS has not expired.
•
Warning 97, Stop Delay is shown in the display if there is a stop signal and the MINIMUM RUNTIME has not expired.
Illustration 4: Short Cycle Protection, Start Delay
Illustration 5: Short Cycle Protection, Stop Delay
3.2.1.4 Anti-reverse Protection
The anti-reverse protection function prevents the compressor scroll set from running in the wrong direction during stop.
The oil return management (ORM) function helps retrieve oil trapped in the cooling system by ramping up periodically (oil boost
speed).
•
The ORM becomes active when the compressor has run below the ORM minimum speed limit for a given time defined by ORM
running time.
•
When ORM is active, the speed increases to a predefined ORM boost speed for a given time defined by ORM boost time
•
Additional a fixed boost interval timer shall trigger the ORM function in case no ORM has run within the defined ORM interval.
Illustration 7: Oil Return Management
3.2.1.6 Data Readouts and Commissioning
The VLT® Motion Control Tool MCT 10 supports the VLT® Compressor Drive CDS 803. The MCT is an efficient tool, for example for
readouts and commissioning.
VLT® Motion Control Tool MCT 10 supports the following readouts:
•
Readouts of alarms, warnings, and fault log in 1 view.
•
Compare a saved project with an online drive.
•
Scope & logging: Easy problem analysis.
•
Offline commissioning.
•
Save/send/mail projects anywhere.
•
Multiple drives in project file. Enables the service organization to be more efficient.
Programmable compressor choices allow downscaling of a drive to operate with an undersized compressor or running an oversized
drive under extreme conditions. This functionality is useful in applications which are outside the specified appliance area:
•
High ambient temperature installations.
•
High altitude installations.
N O T I C E
UL 60730-1 certification restricts for only allowing 1 dedicated compressor combination and does not offer the ability to run an
undersized compressor.
3.2.2 Application Features
The VLT® Compressor Drive CDS 803 offers custom application functions for enhanced performance.
3.2.2.1 Automatic Motor Adaptation (AMA)
Automatic motor adaptation (AMA) is an automated test procedure used to measure the electrical characteristics of the motor. AMA
provides an accurate electronic model of the motor, allowing the drive to calculate optimal performance and efficiency. Running
the AMA procedure also maximizes the automatic energy optimization feature of the drive.
AMA is performed without the motor rotating and without uncoupling the load from the motor.
N O T I C E
Automatic motor adaptation (AMA) is not required when used with a VZH Danfoss compressor.
Electronic thermal protection (ETR) is used in combination with a VZH Danfoss compressor.
ETR calculates motor temperature by measuring current, frequency, and operating time. The drive shows the thermal load on the
motor in percentage and can issue a warning at a programmable overload setpoint. Programmable options at the overload allow
the drive to stop the motor, reduce output, or ignore the condition. Even at low speeds, the drive meets I2t Class 20 electronic
motor overload standards.
Illustration 8: ETR Characteristics
The X-axis shows the ratio between I
motor
and I
nominal. The Y-axis shows the time in seconds before the ETR cuts off and trips
motor
the drive. The curves show the characteristic nominal speed at twice the nominal speed and at 0.2 x the nominal speed. At lower
speed, the ETR cuts off at lower heat due to less cooling of the motor. In that way, the motor is protected from being overheated
even at low speed. The ETR feature calculates the motor temperature based on actual current and speed. The calculated temperature is visible as a readout parameter in parameter 16-18 Motor Thermal.
3.2.2.3 Built-in PID Controller
The built-in proportional, integral, derivative (PID) controller eliminates the need for auxiliary control devices. The PID controller
maintains constant control of closed-loop systems where regulated pressure, flow, temperature, or other system requirements must
be maintained.
The drive can use 2 feedback signals from 2 different devices, allowing the system to be regulated with different feedback requirements. The drive makes control decisions by comparing the 2 signals to optimize system performance.
3.2.2.4 Automatic Restart
The drive can be programmed to restart the motor automatically after a minor trip, such as momentary power loss or fluctuation.
This feature eliminates the need for manual resetting and enhances automated operation for remotely controlled systems. The
number of restart attempts and the duration between attempts can be limited.
3.2.2.5 Flying Start
Flying start allows the drive to synchronize with an operating motor rotating at up to full speed in either direction. This prevents
trips due to overcurrent draw. It minimizes mechanical stress to the system since the motor receives no abrupt change in speed
when the drive starts.
3.2.2.6 Frequency Bypass
In some applications, the system can have operational speeds that create a mechanical resonance. This mechanical resonance can
generate excessive noise and possibly damage mechanical components in the system. The drive has 4 programmable bypass-frequency bandwidths (parameters 4-60 to 4-63). The bandwidths allow the motor to step over speeds that induce system resonance.
3.2.2.7 Motor Preheat
Instead of using a space heater, Danfoss provides motor preheat functionality. To preheat a motor in a cold or damp environment, a
small amount of DC current can be trickled continuously into the motor to protect it from condensation and cold starts.
Coast
Start timer
Set Do X low
Select set-up 2
. . .
Running
Warning
Torque limit
Digital input X 30/2
. . .
=
TRUE longer than..
. . .
. . .
VLT® Compressor Drive CDS 803
Design Guide
Product Overview
3.2.2.8 Programmable Set-ups
The drive has 2 setups that can be independently programmed. Using multi-setup, it is possible to switch between independently
programmed functions activated by digital inputs or a serial command. Independent set-ups are used, for example, to change references, or for day/night or summer/winter operation, or to control multiple motors. The LCP shows the active setup.
Setup data can be copied from drive to drive by downloading the information from the removable LCP or by using VLT® Motion
Control Tool MCT 10.
3.2.2.9 Smart Logic Control (SLC)
Smart logic control (SLC) is a sequence of user-defined actions (see parameter 13-52 SL Controller Action [x]) executed by the SLC
when the associated user-defined event (see parameter 13-51 SL Controller Event [x]) is evaluated as TRUE by the SLC.
The condition for an event can be a particular status, or that the output from a logic rule or a comparator operand becomes TRUE.
The condition leads to an associated action as shown in
Illustration 9.
Illustration 9: SLC Event and Action
Events and actions are each numbered and linked in pairs (states), which means that when event [0] is fulfilled (attains the value
TRUE), action [0] is executed. After the 1st action is executed, the conditions of the next event are evaluated. If this event is evaluated
as true, then the corresponding action is executed. Only 1 event is evaluated at any time. If an event is evaluated as false, nothing
happens in the SLC during the current scan interval and no other events are evaluated. When the SLC starts, it only evaluates event
[0] during each scan interval. Only when event [0] is evaluated as true, the SLC executes action [0] and starts evaluating the next
event. It is possible to program 1–20 events and actions.
When the last event/action has been executed, the sequence starts over again from event [0]/action [0]. An example with 4 events/
actions is shown in Illustration 10:
Illustration 10: Order of Execution when 4 Events/Actions are Programmed
3.2.2.9.1 Comparators
Comparators are used for comparing continuous variables (output frequency, output current, analog input, and so on) to fixed preset values.
Illustration 11: Comparators
3.2.2.9.2 Logic Rules
Combine up to 3 boolean inputs (TRUE/FALSE inputs) from timers, comparators, digital inputs, status bits, and events using the
logical operators AND, OR, and NOT.
Illustration 12: Logic Rules
3.3 VLT® Compressor Drive CDS 803 Protections
The drive has a range of built-in protection functions to protect itself and the compressor during operation. For details of any required setup, in particular compressor parameters, refer to the VLT® Compressor Drive CDS 803 Programming Guide listed in 1.2
Additional Resources for parameter details and programming.
3.3.1 Mains Input Protection
The VLT® Compressor Drive CDS 803 offers various built-in input protections for the 3-phase power terminals L1, L2, and L3.
3.3.1.1 Mains Supply Failure, Momentary Dropouts, and Surges
During a mains dropout, the drive keeps running until the internal DC-link voltage drops below the minimum stop level, which is
typically around 15% or more below the lowest rated supply voltage of the drive. The mains voltage before the dropout and the
motor load determine how long it takes for the drive to coast.
The drive automatically compensates for input voltages ±10% from the mains nominal to provide full rated output current. With
auto restart selected, the drive automatically powers up after a voltage trip. With flying start parameterization, the drive can synchronize to a motor spinning freely after a mains dropout and bring it back to normal operation.
Product Overview
3.3.1.2 Missing Mains Phase Detection
The drive monitors the mains input and reacts according to the programmed configuration if improper conditions, such as missing
or detecting too high imbalance between the input phases.
Operation under severe mains imbalance conditions reduces the lifetime of the drive. Conditions are considered severe if the motor
is operated continously near nominal load. The default setting issues a warning, but automated derating of the load can also be
parameterized among multiple choices.
3.3.2 Output Protection
The VLT® Compressor Drive CDS 803 offers various built-in protection features for the compressor terminals U, V, and W.
3.3.2.1 Short-circuit Protection (Phase-to-phase)
The drive is protected against short circuits on the output side by current measurements. A short circuit between 2 output phases
causes an overcurrent internally and turns off all outputs once the short-circuit current exceeds the maximum limit. A drive that
works correctly limits the current it can draw from the supply. Still, it is recommended to use fuses and/or circuit breakers on the
supply side as protection if there is a component breakdown inside the drive (1st fault). Mains side fuses are mandatory for UL compliance.
N O T I C E
To ensure compliance with IEC 60364 for CE or NEC 2017 for UL, it is mandatory to use fuses and/or circuit breakers.
The drive is protected against ground faults on all output terminals, U, V, and W.
3.3.2.3 Locked Rotor Detection
Sometimes the rotor is locked because of excessive load or other factors preventing the compressor from rotating.
The drive detects the locked rotor situation and trips accordingly to prevent overheating the compressor and the drive.
N O T I C E
In regulation with UL 60730-1 certified products, the locked rotor detection cannot be disabled.
3.3.2.4 Output Phase Loss Detection
The drive monitors all outputs to detect any missing or interrupted connections. If no currents are drawn on any output, it is assumed that no motor is connected and will cause this event to be triggered. If a single phase is lost, an output phase missing event
is triggered. In both scenarios all outputs are turned off. The missing output phase function is enabled by default to avoid motor
damage. Disabling this protection is possible via parameterization.
N O T I C E
In regulation with UL 60730-1 certified products, the output phase loss detection cannot be disabled.
3.3.2.5 Overload Protection
If excessive current outputs or high temperatures are observed for an unwanted period, the protections trip the drive and turn all
the outputs off. The time before the drive trips is controlled by parameterization of the monitored protections.
Voltage limit
The inverter turns off to self-protect the internal components when the maximum voltage limits are reached.
The inverter turns off to self-protect the internal components when the maximum current limits are reached.
Overtemperature
The inverter turns off to self-protect the internal components when the maximum temperature limits are reached.
Electronic thermal relay (ETR)
ETR is an electronic feature that simulates a bimetal relay based on internal measurements. See also 3.2.2.2 Motor Thermal Protec-
tion.
Product Overview
N O T I C E
In regulation wih UL 60730-1 certified products, the output overload conditions, such as motor overload (ETR), cannot be disa-
bled.
3.3.3 Temperature Protection
The VLT® Compressor Drive CDS 803 offers various built-in temperature protection features for monitoring the operation environment.
3.3.3.1 Minimum and Maximum Temperature Protection
The drive has built-in temperature sensors and reacts immediately to critical temperature limits. At low temperature, a warning will
be triggered. If high temperature limits are exceeded, the drive trips on an alarm and turns off all outputs.
3.3.3.2 Automatic Temperature Derating
Automatic temperature derating can be enabled via parameterization to allow continued operation during high temperatures.
3.3.3.3 Temperature-controlled Fans
Sensors in the drive regulate the operation of the internal cooling fans. Often, the cooling fans do not run during low-load operation, when in sleep mode, or in standby. The sensors reduce noise, increase efficiency, and extend the operating life of the fan.
3.3.4 Internal Protection
The VLT® Compressor Drive CDS 803 offers various built-in internal protection features ensuring that the drive is fully operational.
3.3.4.1 DC Overvoltage Protection
The internal DC-link voltage is increased when the motor acts as a generator. This occurs in the following situations:
•
The load drives the motor (at constant output frequency from the drive), that is, the load generates energy.
•
During deceleration (ramp-down) if the moment inertia is high, the friction is low, and the ramp-down time is too short for the
energy to be dissipated as a loss in the drive, the motor, and the installation.
•
Incorrect slip compensation setting may cause higher DC-link voltage.
•
Back EMF from PM motor operation. If coasted at high RPM, the PM motor back EMF may potentially exceed the maximum
voltage tolerance of the drive and cause damage. To prevent this, the maximum output frequency is automatically limited
based on an internal calculation. This calculation is based on motor parameterizations.
Monitoring of the internal voltage ensures that the drive trips when the DC-link voltage is too high. The drive turns off the output to
protect itself when a certain voltage level is reached. Enabling overvoltage control (OVC) reduces the risk of the drive tripping due
to an overvoltage on the DC link. This is controlled by automatically extending the ramp-down time.
3.3.4.2 Internal Faults
The drive has various internal self-monitoring functions which ensure that the drive is fully operational. For warning and alarm details, refer to VLT® Compressor Drive CDS 803 Programming Guide listed in 1.2 Additional Resources.
3.4 Ecodesign for Power Drive Systems
The Ecodesign Directive is the legislative framework that sets requirements on all energy-related products in the domestic, commercial, and industrial sectors throughout Europe.
The Ecodesign requirements are only mandatory within the European Union. These requirements are like the legislative requirements for energy-related products which apply in North America and Australia.
Terms like Complete Drive Module (CDM) and Power Drive Systems (PDS) are used to define the elements in the design. The objective is to make more efficient and fewer energy consuming designs.
The CDM contains the drive controller as well as auxiliary devices and input components.
Illustration 13: Drive System Design
The efficiency classes IE0 to IE2 of the drive controller as specified in IEC 61800-9-2 (EN 50598-2) refer to the 90/100 operating point,
i.e. 90 % motor stator frequency and 100% torque current (see Illustration 14).
Illustration 14: Operating Point according to IEC 61800-9-2 (EN 50598)
Since in the future all component manufacturers will disclose their loss data according to this new standard, optimized applications
can be designed with a wide range of different components. The new Standard allows an accurate preliminary calculation of the
power losses, so that the ROI (Return of Investment) can be reliably determined. Up to now the overall efficiency of speed-regulated
electric motors was estimated with the aid of approximate energy consumption calculations.
It is now possible to determine the total losses of a system for the 8 operating points defined in the standard, including the part
load operation, via a simple addition of power losses. Danfoss helps its customers to avoid having to rely on system solution providers, to ensure that their systems will retain a competitive advantage also in the future.
EC 61800-9-2 (EN 50598-2) shifts the focus from the individual component to the efficiency of the whole drive system. The new
efficiency classes (International Efficiency for Systems, IES)
allow a simple determination of the total losses for a whole drive system (PDS).
Danfoss offers the MyDrive® ecoSmart™ tool, which is available online or as a Smartphone app to assist with the efficiency calcula-
tion. Use MyDrive® ecoSmart™ to:
Look up part load data as defined in IEC 61800-9-2, for VLT® and VACON® drives
•
Calculate efficiency class and part load efficiency for drives and power drive systems
•
Create a report documenting part load loss data and IE or IES efficiency class.
•
For more information, refer to
Refer to Illustration 15 to see the components in the PDS which contribute to losses in the design. Mains cables and the load ma-
chine are not a part of the PDS, even though their losses can be significant and could be a part of the evaluation of the overall
energy efficiency of the installation.
The cabling from the supply must be considered, as the selection of suitable cables is often a problem, especially when dedicated
feeding transformers are installed. From the impedance of the cables, the energy losses are created in the ohmic part. Calculate the
active power losses for a 3-phase system with a star point groundingas follows:
P
= 3 x R x I
L,mains
Because the load, when using drives and motors, also include reactive power and harmonic currents, these parameters also contribute to losses. The ratio between active and apparent power is normally called the power factor. Having a PDS with a power factor
close to 1 result in the lowest losses in the mains. Using filters on the input side of the drive can lower the power factor.
2
L1
3.4.2 Input Filters: Line Reactors and Harmonic Filters
Line reactor
A line reactor is an inductor which is wired in series between a power source and a load. Line reactors, also called input AC reactors,
are typically used in motor drive applications.
The main function of the line reactor lies into its current limiting characteristics. Line reactors also reduce the main harmonics, limit
the inrush currents, and protect drives and motors. An overall improvement of the true power factor and the quality of the input
current waveform can be achieved.
Line reactors are classified by their percent impedance (denoted as percent IZ or %IZ), which is the voltage drop due to impedance,
at the rated current, expressed as a percent of rated voltage. The most common line reactors have either 3% or 5% impedance.
When to use line reactors
It is important to consider the installation environment for the drives. In some situations, distortion from the grid can damage the
drive and precautions must be taken.
A simple menas of prevention is to ensure a minimum of impedance in front of the drive.
When calculating the impedance, the contribution from the supply transformer and the supply cables is also a part of the circuit. In
specific cases, an additional transformer or reactor is recommended. If the conditions listed exist, consider adding impedance (line
reactor or transformer) in front of the drive:
•
The installation site has switched power factor correction capacitors.
•
The installation site has lightening strikes or voltage spikes.
•
The installation site has power interruptions or voltage dips.
Danfoss offers the line reactor program VLT® Line Reactor MCC 103, see
Harmonic filters
The purpose of using harmonic filters is to reduce the distortion on the mains. The distortion is generated by the drives when
switching the voltage to generate a frequency on the output. The harmonics should be limited both seen from energy consumption
perspective and disturbance of other users in the grid.
There are 2 categories of harmonic solutions:
•
Passive.
•
Active.
Passive solutions consist of capacitors, inductors, or a combination of both in different arrangements. The simplest solution is to add
inductors/reactors of typically 3–5% in front of the drive. This added inductance reduces the number of harmonic currents pro-
duced by the drive. More advanced passive solutions combine capacitors and inductors in trap arrangement specially tuned to
eliminate harmonics starting from, for example, the 5th harmonic.
For more details on the Danfoss passive solutions, refer to VLT® Advanced Harmonic Filters AHF 005/AHF 010 Design Guide.
The active solutions determine the exact current that cancels the harmonics present in the circuit and synthesizes and injects that
current into the system. Thus, the active solution mitigates the real-time harmonic disturbances, which makes these solutions effective at any load profile.
For more details on the Danfoss active solutions, refer to VLT® Low Harmonic Drive Operating Instructions, and VLT® Advanced Active Filter AAF 006 Operating Instructions.
Product Overview
3.4.3 Drive, Input Side
RFI (radio frequency interference)
Drives generate radio frequency interference (RFI) due to their variable-width current pulses. Drives and motor cables radiate these
components and conduct them into the mains system.
RFI filters are used to reduce this interference on the mains according to IEC 61800-3 in order not to disturb radio services. Maximum allowed emission depends on the environment where the PDS is used.
The need for reducing the interferences and the losses created by the coils is a trade-off that is hard to influence in the use of drives.
Even though the losses exist, it is important to fulfill the legislation demands for the installation environment.
RFI filter on IT grid
If the drive is supplied from an isolated mains source (IT mains, floating delta) or TT/TN-S mains with grounded leg (grounded delta),
the RFI filter must be turned off.
In the OFF position, the internal capacitors between the chassis (ground), the input RFI filter, and the DC link are cut off. As the RFI
switch is turned off, the drive is not able to meet optimum EMC performance.
By opening the RFI filter switch, the ground leakage currents are also reduced, but not the high-frequency leakage currents caused
by the switching frequency of the drive. It is important to use isolation monitors that are designed for use with power electronics
(IEC 61557-8). For example, Deif type SIMQ, Bender type IRDH 275/375, or similar.
The Danfoss VLT® drives can be ordered with different types of RFI filters. See more details on RFI, the use of RFI filters, and EMC
compliance in 6.5 Electromagnetic Compatibility.
Passive diode rectifier input
The use of diode rectifiers on the input side of the drives are the most cost-effective design. The energy flow goes from the mains to
the load and have low losses. On the other hand, diodes create harmonics in the mains when rectifying and thereby create losses.
These harmonics can be reduced by having DC-link coils, which are used in the Danfoss VLT® drives.
An energy flow from the drive back to the grid is not possible with this design as the energy is generated back from the application
to the DC link. Use a DC chopper and a connected resistor to absorb the energy. This reduces the energy efficiency significantly.
3.4.4 DC Link
The DC link is a power storage facility for the output section of the drive. There are 2 major components to the DC-link section:
•
Capacitors
•
Coils
In Illustration 16 only 1 capacitor is shown, but it is always a series of capacitors.
With Danfoss VLT® drives, this intermediate section always uses DC coils, also known as DC line reactors or DC chokes. For cost considerations, most other drive manufacturers do not offer these DC line reactors as standard equipment. Danfoss regards these coils
as essential for 2 main reasons:
•
The ability to reduce harmonic noise (interference) by 40%.
•
The ability to ride through a temporary loss of power. This allows the drive to avoid numerous unplanned shutdowns.
3.4.5 Drive, Output Side
The output side of the drive contains IGBTs used for generating a variable AC voltage with variable frequency. If no filters are used,
overvoltage spikes, due to reflection of the voltage waveform, can be measured on the motor connection. This situation is often
linked with long motor cables used in the installation and can reach values up to twice the level of the DC-link voltage.
From a user perspective, losses on the output side of the drive can be influenced by using a lower switching frequency, but this also
contributes to higher losses in the motor and filters installed. To optimize energy efficiency, a compromise must be found when
selecting the components used, for example, filters, motor type, and others. Often, output filters are used with the purpose of reducing stress on the insulation.
In the following sections, the aspect of different filter types is discussed in perspective of energy efficiency versus function.
Common-mode filters
Common-mode HF filters are placed between the drive and the motor. They are nanocrystaline cores that mitigate high-frequency
noise in the motor cable (shielded or unshielded) and eliminate bearing currents, and hence Electro Discharge Machining (EDM) or
bearing etching in the motor. Bearing currents caused by drives are also referred to as common-mode currents.
Since the common-mode filters mitigate high frequency, these filters absorb energy and contribute also to losses. Here, the tradeoff is the advantage described compared with the losses.
More information on VLT® Common Mode Filters MCC 105 can be found on www.Danfoss.com.
dU/dt filters
At the IGBTs on the output switch, the voltage is not a clean sinus curve. It contains fast changes in voltage levels over a very short
time. The use of dU/dt filters increases the raise time of the motor voltage to reduce the stress on the motor insulation. If not avoided, the problem will typically not show at once, but after some time, the insulation breaks and creates problems.
The switching frequency influences the losses in the dU/dt filters. These losses can be up to 1% of the rated power. Here, the tradeoff is the possible damage of the motor over time compared with the cost of energy losses.
Danfoss offers the VLT® dU/dt Filter MCC 102 as a possible solution. Find more information on www.Danfoss.com.
Sine-wave filters
A more advanced, but also more costly solution, is using sine-wave filters.
The VLT® Sine-Wave Filter MCC 101 is a differential-mode low-pass filter that suppresses the switching frequency component com-
ing from the drive and smoothes out the phase-to-phase voltage of the drive to become sinusoidal. This reduces the motor insula-
tion stress and bearing currents. By supplying the motor with a sinusoidal voltage waveform, the switching acoustic noise from the
motor is also eliminated.
For more detailed information, see the VLT® Sine-Wave Filter MCC 101 factsheet.
However, this type of filter also produces a voltage drop and there may be a reduction in the available control bandwidth. This can
sometimes make it impossible to use this filter type. Again, as for the dU/dt filter, losses are linked to the switching frequency.
For more detailed information, see the VLT® Output Filters Design Guide.
Product Overview
3.4.6 Motor Cables and Motor
Motor cables
Motor cables introduce mainly ohmic losses: the longer the cables, the more resistance. In general, when correctly selected, the
losses in cables shorter than 25 m (82 ft) can be neglected. In single-wire cables with individual shielding, current causes losses in
the cable shielding. These losses can be neglected when using 3-wire cables.
Motor
There are many different types of motors that can be operated with a drive. The solution for dealing with losses in motors is therefore depending on the individual motor type and installation. In standard IEC 61800-9-2:2017 annex D, a discussion on motor load
and losses is found.
A method to evaluate the losses generated in the motor operated with a drive can be found in the standards IEC 60034-2-1 and IEC
TS 60034-2-4.
The dimensions are only for the physical units. When installing in an application, allow space above and below the units for cooling.
The amount of space for free air passage is listed in 5.2 Side-by-side Installation.
Connect to mains voltage and wait a minimum of 30 minutes before loading the drive.
Over 3 years
Using a DC supply connected directly to the DC-link terminals of the drive, ramp up the voltage 0–100% of
DC bus voltage in increments of 25%, 50%, 75%, and 100% rated voltage under no load for 30 minutes at
each increment. See Illustration 18 for an illustration of this method.
VLT® Compressor Drive CDS 803
Mechanical Installation
Design Guide
Considerations
5 Mechanical Installation Considerations
5.1 Safe Transportation and Storage
Store the drive in a dry location and keep the equipment sealed in its packaging until installation. Follow all instructions on transportation and storage, and make sure that the ambient conditions are according to the specifications given in 4.5 Ambient Condi-
tions.
•
If the package is kept in storage for more than 2 months, keep it in controlled conditions:
-
Make sure that the temperature variation is low.
-
Make sure that the humidity is <50%.
•
Only use lifting and handling equipment rated and suitable for the purpose.
-
Check the weight of the drive and lift the drive with a lifting device if needed. In this case, use the lifting eyes/bars designed
for this purpose.
-
Check the center of gravity on the packaging or on the drive before lifting the drive. Avoid tilting the drive to prevent it
from overturning.
•
Keep the drive in its package until it has to be installed. After unpacking, protect the drive from dust, debris, and moisture.
5.1.1 Reforming the Capacitors
For drives that are in storage and do not have voltage applied, maintenance of the capacitors in the drive may be required.
To avoid damage to the internal DC-link capacitors, reforming is required if the drive has been stored without applying voltage for
more than 3 years. Reforming is possible only with drives with DC terminals. When reforming the capacitors:
•
The reforming voltage must be 1.35–1.45 times the rated mains voltage. If the DC-link voltage stays at a low level and does not
reach approximately 1.41 x mains voltage, contact the local service agent.
•
The supply current draw must not exceed 500 mA.
Table 10: Drive Storage Duration and Reforming Recommendations
Illustration 18: Percent of DC Voltage Increments and Reforming Time
5.2 Side-by-side Installation
The drive can be mounted side by side but requires the clearance specified in Table 11 above and below for cooling.
Table 11: Clearance Required for Cooling
With IP21/NEMA Type1 option kit mounted, a distance of 50 mm (2 in) between the units is required.
N O T I C E
5.3 Operating Environment
In environments with airborne liquids, particles, or corrosive gases, ensure that the IP/Type rating of the equipment matches the
installation environment.
For specifications regarding ambient conditions, see 4.5 Ambient Conditions.
N O T I C E
CONDENSATION
Moisture can condense on the electronic components and cause short circuits. Avoid installation in areas subject to frost. Install
an optional space heater when the drive is colder than the ambient air. Operating in standby mode reduces the risk of condensa-
tion as long as the power dissipation keeps the circuitry free of moisture.
Hot or cold temperatures compromise unit performance and longevity.
Do not operate in environments where the ambient temperature exceeds 55 °C (131 °F).
-
The drive can operate at temperatures down to -10 °C (14 °F). However, proper operation at rated load is only guaranteed at
-
0 °C (32 °F) or higher.
If the temperature exceeds ambient temperature limits, extra air conditioning of the cabinet or installation site is required.
-
5.3.1 Gases
Aggressive gases, such as hydrogen sulfide, chlorine, or ammonia, can damage electrical and mechanical components of a drive.
Contamination of the cooling air can also cause the gradual decomposition of PCB tracks and door seals. Aggressive contaminants
are often present in sewage treatment plants or swimming pools. A clear sign of an aggressive atmosphere is corroded copper.
In aggressive atmospheres, restricted IP enclosures are recommended along with conformal-coated circuit boards.
The electronic components are, as standard, coated as per IEC60721-3-3, class 3C2. For harsh and aggressive environments, coating
as per IEC60721-3-3, class 3C3 is available.
Table 12: Conformal Coating Class Ratings
1
Maximum values are transient peak values and are not to exceed 30 minutes per day.
Refer to 7.1 Drive Configurator for ordering the correct protective rating.
5.3.2 Dust
Installation of drives in environments with high dust exposure is often unavoidable. Consider the following when installing drives in
such environments:
•
Reduced cooling.
•
Cooling fans.
•
Periodic maintenance.
Reduced cooling
Dust forms deposits on the surface of the device and inside on the circuit boards and the electronic components. These deposits act
as insulation layers and hamper heat transfer to the ambient air, reducing the cooling capacity. The components become warmer.
This causes accelerated aging of the electronic components and the service life of the unit decreases. Dust deposits on the heat sink
in the back of the unit also decrease the service life of the unit.
The airflow for cooling the unit is produced by cooling fans, usually on the back of the unit. The fan rotors have small bearings into
which dust can penetrate and act as an abrasive. This leads to bearing damage and fan failure.
Periodic maintenance
Under the conditions described above, it is recommended to clean the drive during periodic maintenance. Remove dust from the
heat sink and fans.
Considerations
5.3.3 Air Humidity
The drive has been designed to meet the IEC/EN 60068-2-3 standard, EN 50178 9.4.2.2 at 50 °C (122 °F).
5.3.4 Vibration and Shock
The drive has been tested according to the following standards:
•
IEC/EN 60068-2-6: Vibration (sinusoidal) - 1970
•
IEC/EN 60068-2-64: Vibration, broad-band random
The drive complies with the requirements that exist for units mounted on the walls and floors of production premises, and in panels
bolted to walls or floors.
5.3.5 Derating for Ambient Temperature and Switching Frequency
Ensure that the ambient temperature measured over 24 h is at least 5 °C (9 °F) lower than the maximum ambient temperature that
is specified for the drive. If the drive is operated at high ambient temperature, decrease the constant output current. If the ambient
temperature is higher than 50 °C (122 °F) or the installation by altitude is higher than 1000 m (3281 ft), a larger VLT® Compressor
Drive CDS 803 might be needed to run an undersized compressor. Consult Danfoss for support.
5.3.5.1 Derating Curves, 6.0, 7.5, and 10 kW
Illustration 19: 400 V IP20 H3 6.0–7.5 kW (8.0–10 hp)
Illustration 20: 200 V IP20 H4 6.0–7.5 kW (8.0–10 hp)
Drives in the power range 18.5–22 kW are able to deliver 100% current in ambient temperatures up to 52 °C (125 °F) with a default
switching frequency of 5.0 kHz (f_sw). If the switching frequency is increased, the following derating curves apply.
Illustration 23: 400 V IP20 H5 18.5–22 kW (25–30 hp)
5.3.5.3 Derating Curves, 30 kW
Drives in the power range 30 kW are able to deliver 100% current in ambient temperatures up to 45 °C (113 °F) with a default
switching frequency of 4.0 kHz (f_sw). If the switching frequency is increased, the following derating curves apply.
5.3.6 Derating for Low Air Pressure and High Altitudes
The cooling capability of air is decreased at low air pressure. For altitudes above 2000 m (6562 ft), contact Danfoss regarding PELV.
Below 1000 m (3281 ft) altitude, derating is not necessary. For altitudes above 1000 m (3281 ft), decrease the ambient temperature
or the maximum output current. Decrease the output by 1% per 100 m (328 ft) altitude above 1000 m (3281 ft) or reduce the maximum ambient cooling air temperature by 1 °C (1.8 °F) per 200 m (656 ft).
5.4 IP21/NEMA Type 1 Enclosure Kit
If environment, air quality, or surroundings require extra protection, an IP21/NEMA Type 1 kit can be ordered, see 7.3 Accessories
and Spare Parts. The IP21/NEMA Type 1 is an optional enclosure element available for IP20 units. If the enclosure kit is used, an IP20
unit is upgraded to comply with enclosure IP21/NEMA Type 1.
N O T I C E
The IP21/IP21 are not suitable for outdoor mounting.
If the compressor application makes noise or vibrations at certain frequencies, adjust the following parameters to avoid resonance
problems within the system.
•
Upper and lower frequency limits, Parameter group 4-6* Speed Bypass.
•
Switching pattern and switching frequency, parameter group 14-0* Inverter Switching.
5.6 Recommended Disposal
When the AC drive reaches the end of its service life, its primary components can be recycled.
Before the materials can be removed, the drive must be disassembled. Product parts and materials can be dismantled and separa-
ted. Generally, all metals, such as steel, aluminum, copper and its alloys, and precious metals can be recycled as material. Plastics,
This symbol on the product indicates that it may not be disposed of as household waste.Do not dispose of equipment
containing electrical components together with domestic waste.
It must be handed over to the applicable take-back scheme for the recycling of electrical and electronic equipment.
Dispose of the product through channels provided for this purpose.
Comply with all local and currently applicable laws and regulations.
VLT® Compressor Drive CDS 803
Mechanical Installation
Design Guide
rubber, and cardboard can be used in energy recovery. Printed circuit boards and large electrolytic capacitors (diameter >2.5 cm)
need further treatment according to IEC 62635 guidelines. To ease recycling, plastic parts are marked with an appropriate identification code.
Contact your local Danfoss office for further information on environmental aspects and recycling instructions for professional recyclers. End of life treatment must follow international and local regulations.
All drives are designed and manufactured in accordance with Danfoss company guidelines on prohibited and restricted substances.
A list of these substances is available at www.danfoss.com.
All cabling must comply with national and local regulations on cable cross-sections and ambient temperature. Copper conductors
are required. 75 °C (167 °F) is recommended.
6.1.1 Fastener Torque Ratings
Table 14: Tightening Torques for Enclosure Sizes H3–H6, 3x200–240 V & 3x380–480 V
6.2 Fuses and Circuit Breakers
Fuses and circuit breakers ensure that possible damage to the drive is limited to damage inside the unit. Danfoss recommends fuses
on the supply side as protection. For further information, see the application note Fuses and Circuit Breakers found on www.dan-
foss.com under Service and support/Documentation/Manuals & guides.
N O T I C E
Use of fuses on the supply side is mandatory for IEC 60364 (CE) and NEC 2009 (UL) compliant installations.
6.2.1 Recommendation of Fuses and Circuit Breakers
6.3.4 Connecting to Mains and Compressor Terminals
•
Tighten all terminals in accordance with the information provided in 6.1.1 Fastener Torque Ratings.
•
Keep the compressor cable as short as possible to reduce the noise level and leakage currents.
•
Use a shielded/armored compressor cable to comply with the EMC emission specifications and connect this cable to both the
decoupling plate and the compressor. Also see 6.5.5 EMC-compliant Electrical Installation.
1.
Connect the ground cable to the ground terminal, then connect the mains supply to terminals L1, L2, and L3.
Connect the ground cable to the ground terminal, then connect the compressor to terminals U, V, and W.
Electrical Installation
Considerations
Table 16: Connection of Compressor to Terminals
6.3.4.1 IT Grid Installations
N O T I C E
If the drive is supplied from an isolated mains source or mains with grounded leg, the RFI filter is recommended to be disabled,
see 6.5.8 RFI Filter Switch.
Once disabled, the filter capacitors between the chassis and the DC link are cut off to avoid damage to the DC link and to reduce the
ground capacity currents, according to IEC 61800-3. If optimum EMC performance is required, avoid exceeding overvoltage limits
within the DC bus by making sure that the energy charged into the DC link through the RFI filter is either discharged via loading the
DC bus terminals or output terminals U, V, and W.
It is important to use isolation monitors that are rated for use with power electronics (IEC 61557-8).
C A U T I O N
Ensure that the supply voltage does not exceed 440 V (3x380–480 V units) when connected to an IT mains source.
Remove the terminal cover to access the control terminals.
Use a flat-edged screwdriver to push down the lock lever of the terminal cover under the LCP, then remove the terminal cover as
The following illustration shows all the drive control terminals. Applying start (terminal 18), connection between terminals 12-27,
and an analog reference (terminal 53 or 54, and 55) make the drive run.
The digital input mode of terminal 18, 19, 27, and 29 is set in parameter 5-00 Digital Input Mode (PNP is default value).
Considerations
Illustration 32: Control Terminals
6.4 Setting Up RS485 Serial Communication
6.4.1 RS485 Features
RS485 is a 2-wire bus interface compatible with multi-drop network topology. This interface contains the following features:
•
Ability to select from the following communication protocols:
-
FC (default protocol)
-
Modbus RTU
•
Functions can be programmed remotely using the RS485 connection or in parameter group 8-** Communications and Options.
•
A switch (BUS TER) is provided on the control card for bus termination resistance.
N O T I C E
Altering between the supported communication protocols can be accessed and changed via the LCP as parameter 8-30 Protocol is
not available in VLT® Motion Control Tool MCT 10.
6.4.2 Configuring RS485 Serial Communication
Procedure
1.
Connect RS485 serial communication wiring to terminals (P RS485) 68 and (N RS485) 69.
-
Use shielded serial communication cable.
-
Properly ground the wiring. Refer to 6.5.5 EMC-compliant Electrical Installation.
Configure all required settings such as address, baud rate, and so on in parameter group 8-** Communications and Options.
For more details on parameters, refer to VLT® Compressor Drive CDS 803 Programming Guide listed in 1.2 Additional Re-
sources.
Example
Illustration 33: RS485 Wiring Connection
Considerations
6.5 Electromagnetic Compatibility
Electrical devices both generate interference and are affected by interference from other generated sources. The electromagnetic
compatibility (EMC) of these effects depends on the power and the harmonic characteristics of the devices. Uncontrolled interaction
between electrical devices in a system can degrade compatibility and impair reliable operation. Interference takes the form of the
following:
•
Electrostatic discharges
•
Rapid voltage fluctuations
•
High-frequency interference
Electrical interference is most commonly found at frequencies in the range 150 kHz to 30 MHz. Airborne interference from the drive
system in the range 30 MHz to 1 GHz is generated from the inverter, motor cable, and the motor.
Capacitive currents in the motor cable, coupled with a high dU/dt from the motor voltage, generate leakage currents. See Illustra-
tion 34. Shielded motor cables have higher capacitance between the phase wires and the shield, and again between the shield and
ground. This added cable capacitance, along with other parasitic capacitance and motor inductance, changes the electromagnetic
emission signature produced by the unit. The change in electromagnetic emission signature occurs mainly in emissions less than
5 MHz. Most of the leakage current (I1) is carried back to the unit through the PE (I3), leaving only a small electromagnetic field (I4)
from the shielded motor cable. The shield reduces the radiated interference but increases the low-frequency interference on the
mains.
Illustration 34: Electric Model Showing Possible Leakage Currents
YesNoYesNoYesNoYesNoYesNoYes
H4 RFI filter (EN 55011 A1, EN/IEC61800-3 C2)
6.0– 10 kW
(8.0– 15
hp)
––25 (82)
50 (164)
–
20 (66)
––Yes
Yes–No
H2 RFI filter (EN 55011 A2, EN/IEC 61800-3 C3)
18–30 kW
(25– 40
hp)
5 (16.4)
–––––
Yes–No–No
–
VLT® Compressor Drive CDS 803
Electrical Installation
Design Guide
Considerations
6.5.1 EMC Emission Test Results
The following test results have been obtained using a system with a drive, a shielded control cable, a control box with potentiometer, and a shielded motor cable.
Table 17: EMC Emission Test Results
6.5.2 Emission Requirements
According to the EMC product standard for AC drives, EN/IEC 61800-3:2004, the EMC requirements depend on the intended use of
the drive. Four categories are defined in the EMC product standard. The definitions of the 4 categories together with the requirements for mains supply voltage conducted emissions are given in Table 18.
Conducted emission requirement according to
the limits given in EN
55011
C1
Drives installed in the 1st environment (home and office) with a supply voltage less than
1000 V.
Class B
C2
Drives installed in the 1st environment (home and office) with a supply voltage less than
1000 V, which are neither plug-in nor movable and are intended for installation and
commissioning by a professional.
Class A Group 1
C3
Drives installed in the 2nd environment (industrial) with a supply voltage lower than
1000 V.
Class A Group 2
C4
Drives installed in the 2nd environment (industrial) with a supply voltage equal to or
above 1000 V or rated current equal to or above 400 A or intended for use in complex
systems.
No limit line. Make an EMC
plan.
Environment
Generic standard
Conducted emission requirement according to the limits
given in EN 55011
1st environment (home and office)
EN/IEC 61000-6-3 Emission standard for residential, commercial, and light industrial environments.
Class B
2nd environment (industrial environment)
EN/IEC 61000-6-4 Emission standard for industrial environments.
Class A Group 1
VLT® Compressor Drive CDS 803
Design Guide
Table 18: Emission Requirements
When the generic emission standards are used, the drives are required to comply with the limits in Table 19.
Electrical Installation
Considerations
Table 19: Emission Limit Classes
N O T I C E
According to the EMC Directive, a system is defined as a combination of several types of equipment, finished products, and/or
components combined, designed and/or put together by the same person (system manufacturer) intended to be placed on the
market for distribution as a single functional unit for an end user and intended to be installed and operated together to perform a
specific task. The EMC Directive applies to products/systems and installations, but in case the installation is built up of CE marked
products/systems the installation can also be considered compliant with the EMC Directive. Installations shall not be CE marked.
According to the EMC Directive, Danfoss Drives as a manufacturer of product/systems is responsible for obtaining the essential
requirements of the EMC Directive and attaching the CE mark. For systems involving load sharing and other DC terminals, Dan-
foss Drives can only ensure compliance to the EMC Directive when end users connect combinations of Danfoss Drives products
as described in our technical documentation.
If any 3rd-party products are connected to the load share or other DC terminals on the AC drives, Danfoss Drives cannot guaran-
tee that the EMC requirements are fulfilled.
6.5.3 Immunity Requirements
The immunity requirements for drives depend on the environment in which they are installed. The requirements for the industrial
environment are higher than the requirements for the home and office environment. All Danfoss VLT® drives comply with the requirements for the industrial environment and therefore also comply with the lower requirements for home and office environment
with a large safety margin.
To document immunity against burst transient from electrical phenomena, the following immunity tests have been carried out on a
system consisting of:
•
A drive (with options if relevant).
•
A shielded control cable.
•
A control box with potentiometer, motor cable, and motor.
The tests were performed in accordance with the following basic standards:
•
EN 61000-4-2 (IEC 61000-4-2) Electrostatic discharges (ESD): Simulation of electrostatic discharges from human beings.
•
EN 61000-4-3 (IEC 61000-4-3) Radiated immunity: Amplitude modulated simulation of the effects of radar and radio communication equipment and mobile communications equipment.
•
EN 61000-4-4 (IEC 61000-4-4) Burst transients: Simulation of interference brought about by switching a contactor, relay, or
similar devices.
•
EN 61000-4-5 (IEC 61000-4-5) Surge transients: Simulation of transients brought about by, for example, lightning that strikes
near installations.
•
EN 61000-4-6 (IEC 61000-4-6) RF Common mode: Simulation of the effect from radio-transmission equipment joined by connection cables.
The immunity requirements should follow product standard IEC 61800-3. See
Table 20: EMC Immunity, Voltage Range: 200–240 V, 380–480 V
Table 20.
Considerations
1
Injection on cable shield.
AD: Air Discharge
CD: Contact Discharge
CM: Common Mode
DM: Differential Mode
Power supply (SMPS) including signal isolation of DC
link2Gate drive for the IGBTs
3
Current transducers
4
Opto-coupler, brake module (optional)
5
Internal inrush, RFI, and temperature measurement
circuits
6
Custom relays
7
Mechanical brake
VLT® Compressor Drive CDS 803
Electrical Installation
Design Guide
Considerations
6.5.4 EMC Compatibility
N O T I C E
OPERATOR RESPONSIBILITY
According to the EN 61800-3 standard for variable-speed drive systems, the operator is responsible for ensuring EMC compliance.
Manufacturers can offer solutions for operation conforming to the standard. Operators are responsible for applying these solu-
tions and for paying the associated costs.
There are 2 options for ensuring electromagnetic compatibility:
•
Eliminate or minimize interference at the source of emitted interference.
•
Increase the immunity to interference in devices affected by its reception.
RFI filters
The goal is to obtain systems that operate stably without radio frequency interference between components. To achieve a high
level of immunity, use drives with high-quality RFI filters.
N O T I C E
In a residential environment, this product can cause radio interference, in which case supplementary mitigation measures may be
required.
PELV and galvanic isolation compliance
All control and relay terminals comply with PELV (excluding grounded delta leg above 400 V). To obtain galvanic (ensured) isolation,
fulfill requirements for higher isolation and provide the relevant creepage/clearance distances. These requirements are described in
EN 61800-5.1.
Electrical isolation is provided as shown in Illustration 35. The components described comply with both PELV and the galvanic isolation requirements.
To obtain an EMC-compliant installation, be sure to follow all electrical installation instructions.
Also, remember to practice the following:
•
When using relays, control cables, a signal interface, fieldbus, or brake, connect the shield to the enclosure at both ends. If the
ground path has high impedance, is noisy, or is carrying current, break the shield connection on 1 end to avoid ground current
loops.
•
Convey the currents back to the unit using a metal mounting plate. Ensure good electrical contact from the mounting plate by
securely fastening the mounting screws to the drive chassis.
•
Use shielded cables for motor output cables. An alternative is unshielded motor cables within metal conduit.
•
Ensure that motor and brake cables are as short as possible to reduce the interference level from the entire system.
•
Avoid placing cables with a sensitive signal level alongside motor and brake cables.
•
For communication and command/control lines, follow the particular communication protocol standards. For example, USB
must use shielded cables, but RS485/ethernet can use shielded UTP or unshielded UTP cables.
•
Ensure that all control terminal connections are rated protective extra low voltage (PELV).
N O T I C E
TWISTED SHIELD ENDS (PIGTAILS)
Twisted shield ends increase the shield impedance at higher frequencies, which reduces the shield effect and increases the leak-
age current.
Use integrated shield clamps instead of twisted shield ends.
-
N O T I C E
SHIELDED CABLES
If shielded cables or metal conduits are not used, the unit and the installation do not meet regulatory limits on radio frequency
(RF) emission levels.
N O T I C E
EMC INTERFERENCE
Failure to isolate power, motor, and control cables can result in unintended behavior or reduced performance.
Use shielded cables for motor and control wiring.
-
Provide a minimum 200 mm (7.9 in) separation between mains input, motor cables, and control cables.
-
N O T I C E
INSTALLATION AT HIGH ALTITUDE
There is a risk of overvoltage. Isolation between components and critical parts could be insufficient and may not comply with
PELV requirements.
Use external protective devices or galvanic isolation. For installations above 2000 m (6500 ft) altitude, contact Danfoss re-
-
garding protective extra low voltage (PELV) compliance.
N O T I C E
PROTECTIVE EXTRA LOW VOLTAGE (PELV) COMPLIANCE
Prevent electric shock by using PELV electrical supply and complying with local and national PELV regulations.
Minimum 200 mm (7.9 in) between control cables,
motor cables, and mains cables
5
Mains supply options, see IEC/EN 61800-5-1
6
Bare (unpainted) surface
7
Star washers
8
Brake cable (shielded) – not shown, but same
gounding principle applies as for motor cable
9
Motor cable (shielded)
10
Mains cable (unshielded)
11
Output contactor
12
Cable insulation stripped
13
Common ground busbar. Follow local and national
requirements for cabinet grounding.
14
Brake resistor
15
Terminal box
16
Connection to motor
17
Motor
18
EMC cable gland
e75za166.14
0.010.1110100
10ˉ²
10ˉ³
10ˉ¹
1
10¹
10²
10⁴
10³
10⁵
1
mΩ/m
MHz
2
3
4
5
6
7
VLT® Compressor Drive CDS 803
Electrical Installation
Design Guide
Considerations
6.5.6 EMC-compliant Cables
To optimize EMC immunity of the control cables and emission from the motor cables, use braided shielded/armored cables.
The ability of a cable to reduce the in- and outgoing radiation of electric noise depends on the transfer impedance (ZT). The shield of
a cable is normally designed to reduce the transfer of electric noise. However, a shield with a lower transfer impedance (ZT) value is
more effective than a shield with a higher transfer impedance (ZT).
Cable manufacturers rarely state the transfer impedance (ZT), but it is often possible to estimate transfer impedance (ZT) by assessing the physical design of the cable.
Transfer impedance (ZT) can be assessed based on the following factors:
•
The conductibility of the shield material.
•
The contact resistance between the individual shield conductors.
•
The shield coverage, that is, the physical area of the cable covered by the shield - often stated as a percentage value.
Single-layer braided copper wire with varying percentage shield coverage. This is the typical reference
cable.
4
Double-layer braided copper wire.
5
Twin layer of braided copper wire with a magnetic,
shielded/armored intermediate layer.
6
Cable that runs in copper tube or steel tube.
7
Lead cable with 1.1 mm (0.04 in) wall thickness.
1
2
PE
FC
PE
PLC
e30bb922.12
PEPE
<10 mm
1
Minimum 16 mm2 (6 AWG)
2
Equalizing cable
100nF
FC
PE
PE
PLC
<10 mm
e30bb609.12
PE
FC
PE
FC
e30bb923.12
PEPE
69
68
61
69
68
61
1
2
<10 mm
1
Minimum 16 mm2 (6 AWG)
2
Equalizing cable
VLT® Compressor Drive CDS 803
Electrical Installation
Design Guide
Considerations
6.5.7 Shielded Control Cables
Usually, the preferred method is to secure control and serial communication cables with shielding clamps provided at both ends to
ensure the best possible high frequency cable contact.
If the ground potential between the drive and the PLC is different, electric noise could disturb the entire system. Solve this problem
by fitting an equalizing cable as close as possible to the control cable. Minimum cable cross-section: 16 mm2 (6 AWG).
Illustration 38: Shielding Clamps at Both Ends
6.5.7.1 50/60 Hz Ground Loops
With long control cables, ground loops may occur. To eliminate ground loops, connect 1 end of the shield to the ground with a
100 nF capacitor (keeping leads short).
Illustration 39: Connection with a 100 nF Capacitor
6.5.7.2 Avoid EMC Noise on Serial Communication
This terminal is connected to ground via an internal RC link. Use twisted-pair cables to reduce interference between conductors. The
recommended method is shown in the following illustration.
Illustration 40: Twisted-pair Cables
Alternatively, the connection to terminal 61 can be omitted.
Illustration 41: Twisted-pair Cables without Terminal 61
Considerations
6.5.8 RFI Filter Switch
For power sizes 6.0–10 kW (8.0–15 hp), disable the RFI filter by removing the screw.
For power sizes 18.5–22 kW (20–25 hp), removing the screw does not have any electrical effect and does not alter any RFI settings.
For power size 30 kW (40 hp), no options are available for disabling the RFI filter.
If reinserted, use only M3x12 screw.
6.6 Harmonics Emission
A drive takes up a non-sinusoidal current from mains, which increases the input current I
formed with a Fourier analysis and split into sine-wave currents with different frequencies, that is, different harmonic currents I
with 50 Hz basic frequency:
Table 21: Harmonic Currents
The harmonics do not affect the power consumption directly, but increase the heat losses in the installation (transformer, cables).
So, in plants with a high percentage of rectifier load, maintain harmonic currents at a low level to avoid overload of the transformer
and high temperature in the cables.
IEC/EN 61000-3-2 Class A for 3-phase balanced equipment (for professional equipment only up to 1 kW (1.3 hp) total
power).
2
IEC/EN 61000-3-12 Equipment 16–75 A and professional equipment as from 1 kW (1.3 hp) up to 16 A phase current.
Individual harmonic current In/I1 (%)
I5I7I11I
13
Actual 6.0–10 kW (8.0–15 hp), IP20, 200 V (typical)
32.6
16.6
8.0
6.0
Limit for R
sce
≥120
402515
10
Harmonic current distortion factor (%)
THDi
PWHD
Actual 6.0–10 kW (8.0–15 hp), 200 V (typical)
39
41.4
Limit for R
sce
≥120
48
46
Individual harmonic current In/I1 (%)
I5I7I11I
13
Actual 6.0–22 kW (8.0–30 hp), IP20, 380–480 V (typical)
36.7
20.8
7.6
6.4
Limit for R
sce
≥120
402515
10
Harmonic current distortion factor (%)
VLT® Compressor Drive CDS 803
Electrical Installation
Design Guide
Considerations
N O T I C E
Some of the harmonic currents might disturb communication equipment connected to the same transformer or cause resonance
with power factor correction batteries.
To ensure low harmonic currents, the drive is equipped with DC-link coils as standard. This normally reduces the input current I
RMS
by 40%.
The voltage distortion on the mains supply voltage depends on the size of the harmonic currents multiplied by the mains impe-
dance for the frequency in question. The total voltage distortion THDv is calculated based on the individual voltage harmonics using this formula:
THD % = U
+ U
5
2
+ ... + U
7
2
N
2
(UN% of U)
6.6.1 Harmonics Emission Requirements
Equipment is connected to the public supply network.
Table 22: Connected Equipment
6.6.2 Harmonics Test Results (Emission)
Power sizes up to 10 kW (15 hp) [200–240 V AC] comply with IEC/EN 61000-3-12, Table 4. Power sizes up to 30 kW (40 hp) [380–
480 V AC] comply with IEC/EN 61000-3-2 Class A and IEC/EN 61000-3-12, Table 4.
Table 23: Harmonic Current 6.0–10 kW (8.0–15 hp), 200 V
Table 24: Harmonic Current 6.0–22 kW (8.0–30 hp), 380–480 V
Table 25: Harmonic Current 30 kW (40 hp), 380–480 V
Electrical Installation
Considerations
If the short-circuit power of the supply Ssc is greater than or equal to:
S
= 3 × R
SC
at the interface point between the user’s supply and the public system (R
SCE
× U
mains
× I
= 3 × 120 × 400 × I
equ
equ
sce
).
The installer or user of the equipment is responsible for ensuring that the equipment is connected only to a supply with a shortcircuit power Ssc greater than or equal to what is specified above. If necessary, consult the distribution network operator. Other
power sizes can be connected to the public supply network by consultation with the distribution network operator.
Compliance with various system level guidelines: The harmonic current data in Table 23 to Table 25 are given in accordance with
IEC/EN 61000-3-12 with reference to the Power Drive Systems product standard. They may be used as the basis for calculation of the
harmonic currents' influence on the power supply system and for the documentation of compliance with relevant regional guidelines: IEEE 519 -1992; G5/4.
If there is a need for further reduction of harmonic currents, passive or active filters in front of the drives can be installed. Consult
Danfoss for further information.
6.7 Galvanic Isolation (PELV)
All control terminals and output relay terminals are galvanically isolated from mains power, which completely protects the controller circuitry from the input current. The output relay terminals require their own grounding. This isolation meets the stringent protective extra-low voltage (PELV) requirements for isolation.
The components that make up the galvanic isolation are illustrated in Illustration 43:
Illustration 43: Galvanic Isolation (PELV)
6.8 Ground Leakage Current
Follow national and local codes regarding protective earthing of equipment where leakage current exceeds 3.5 mA.
Drive technology implies high frequency switching at high power. This generates a leakage current in the ground connection.
Reinforce grounding with the following protective earth connection requirements:
•
Ground wire (terminal 95) of at least 10 mm2 (8 AWG) cross-section.
•
2 separate ground wires both complying with the dimensioning rules.
See EN/IEC 61800-5-1 and IEC EN 62477-1 for further information.
Considerations
W A R N I N G
DISCHARGE TIME
Touching the electrical parts, even after the equipment has been disconnected from mains, could be fatal.
Make sure that other voltage inputs have been disconnected, such as load sharing (linkage of DC-link), and the motor con-
-
nection for kinetic back-up.
Before touching any electrical parts, wait at least the amount of time indicated in the safety chapter. Shorter time is allowed
-
only if indicated on the nameplate for the specific unit.
W A R N I N G
LEAKAGE CURRENT HAZARD
Leakage currents exceed 3.5 mA. Failure to ground the drive properly can result in death or serious injury.
Ensure the correct grounding of the equipment by a certified electrical installer.
-
6.8.1 Using a Residual Current Device (RCD)
Where residual current devices (RCDs), also known as earth leakage circuit breakers (ELCBs), are used, comply with the following:
•
Use RCDs of type B only, which are capable of detecting AC and DC currents.
•
Use RCDs with an inrush delay to prevent faults caused by transient ground currents.
•
Dimension RCDs according to the system configuration and environmental considerations.
The leakage current includes several frequencies originating from both the mains frequency and the switching frequency. Whether
the switching frequency is detected depends on the type of RCD used.
Illustration 46: Mains Contributions to Leakage Current
The amount of leakage current detected by the RCD depends on the cut-off frequency of the RCD.
SXXX: Latest release in combination with UL 508C
S096: Latest release in combination with UL/EN/IEC 60730-1
28
Software language
X: Standard
29–30
A options
AX: No A options
31–32
B options
BX: No B options
33–34
C0 options
CX: No C options
VLT® Compressor Drive CDS 803
Design Guide
How to Order
7 How to Order
7.1 Drive Configurator
Illustration 48: Type Code Example
Configure the right drive for the right application from the internet-based Drive Configurator and generate the type code string.
The Drive Configurator automatically generates an 8-digit sales number to be delivered to the local sales office. Furthermore, it is
possible to establish a project list with several products and send it to a Danfoss sales representative.
The Drive Configurator can be found on the global website: www.danfoss.com/drives.
A signal transmitted to the analog inputs 53 or 54 (voltage or current).
Current input: 0–20 mA and 4–20 mA
Voltage input: 0–10 V DC
Analog inputs
The analog inputs are used for controlling various functions of the drive.
There are 2 types of analog inputs:
Current input, 0–20 mA, and 4–20 mA
Voltage input, 0 V DC to +10 V DC
Analog outputs
The analog outputs can supply a signal of 0–20 mA, 4–20 mA.
Break-away torque
e75za078.10
(1)
(2)
(3)
Bus reference
A signal transmitted to the serial communication port (FC port).
Control command
Functions are divided into 2 groups.
Functions in group 1 have higher priority than functions in group 2.
Group 1
Reset, coast stop, reset and coast stop, quick stop, DC brake,
stop, the [OFF] key.
Motor frequency when the jog function is activated (via digital terminals).
IMMotor current (actual).
I
M,N
Rated motor current (nameplate data).
Intermittent duty cycle
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.
lsb
Least significant bit.
MCM
Short for "mille circular mil", an American measuring unit for cable crosssection. 1 MCM=0.5067 mm
2
msb
Most significant bit.
n
M,N
Nominal motor speed (nameplate data).
Online/offline parameters
Changes to online parameters are activated immediately after the data value is changed. Press [OK] to activate changes to off-line parameters.
PI controller
The PI controller maintains the required speed, pressure, temperature, and
so on, by adjusting the output frequency to match the varying load.
P
M,N
Rated motor power (nameplate data in kW or hp).
Power factor
The power factor is the relation between I1 and I
RMS
Powerfactor =
3 ×U × I
1cosϕ
3 ×U × I
RMS
The power factor for 3-phase control:
Powerfactor =
I1 ×cosϕ1
I
RMS
=
I
1
I
RMS
sincecosϕ1 = 1
The power factor indicates to which extent the drive imposes a load on the
mains supply.
The lower the power factor, the higher the I
RMS
for the same kW perform-
ance.
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 DC coils in the drive produce a high-power factor, which minimizes the
imposed load on the mains supply.
Preset reference
A defined preset reference to be set from -100% to +100% of the reference
range. Selection of 8 preset references via the digital terminals.
Save parameter settings in 4 set-ups. Change between the 4 parameter setups and edit 1 set-up, while another set-up is active.
Slip compensation
The drive compensates for the compressor slip by giving the frequency a
supplement that follows the measured compressor load keeping the compressor speed almost constant.
Start-disable command
A stop command belonging to Group 1 control commands, see the table
Function Groups under Control Command.
Stop command
A stop command belonging to Group 1 control commands, see the table
Function Groups under Control Command.
Thermistor
A temperature-dependent resistor placed on the drive or the compressor.
Trip
A state entered in fault situations, for example, if the drive is subject to an
overtemperature or when the drive is protecting the compressor, process,
or mechanism. The drive prevents a restart until the cause of the fault has
disappeared. To cancel the trip state, restart the drive. Do not use the trip
state for personal safety.
Trip lock
The drive enters this state in fault situations to protect itself. The drive requires physical intervention, for example when there is a short circuit on
the output. A trip lock can only be canceled by disconnecting mains, removing the cause of the fault, and reconnecting the drive. Restart is prevented until the trip state is canceled by activating reset or, sometimes, by being programmed to reset automatically. Do not use the trip lock state for
personal safety.
UMInstant motor voltage.
U
M,N
Rated motor voltage (nameplate data).
VT characteristics
Variable torque characteristics used for pumps and fans.
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also applies to products already on order provided that such alterations can be made without subsequential changes being necessary in specifications already agreed. All
trademarks in this material are property of the respective companies. Danfoss and the Danfoss logotype are trademarks of Danfoss A/S. All rights reserved.