Danfoss CDS 803 Design guide

Design Guide

VLT® Compressor Drive CDS 803

6–30 kW

vlt-drives.danfoss.com

VLT® Compressor Drive CDS 803
Design Guide	Contents

Contents

1 Introduction		7
1.1	Purpose of this Design Guide	7
1.2	Additional Resources	7
	1.2.1 Supplementary Documentation	7
	1.2.2 VLT® Motion Control Tool MCT 10 Software Support	7
1.3	Manual and Software Version	7
1.4	Approvals and Certifications	7

2 Safety		9
2.1	Safety Symbols	9
2.2	Qualified Personnel	9
2.3	Safety Precautions	9

3 Product Overview			11
3.1 VLT® Compressor Drive CDS 803 Family Overview			11
3.2 VLT® Compressor Drive CDS 803 Features			12
3.2.1	Compressor Features		12
	3.2.1.1	Secure Start-up	12
	3.2.1.2	Compressor Minimum Speed Detection	13
	3.2.1.3	Short-cycle Protection	14
	3.2.1.4	Anti-reverse Protection	14
	3.2.1.5	Oil Return Management	15
	3.2.1.6	Data Readouts and Commissioning	15
	3.2.1.7	Undersized Compressor	16
3.2.2	Application Features		16
	3.2.2.1	Automatic Motor Adaptation (AMA)	16
	3.2.2.2	Motor Thermal Protection	16
	3.2.2.3	Built-in PID Controller	17
	3.2.2.4	Automatic Restart	17
	3.2.2.5	Flying Start	17
	3.2.2.6	Frequency Bypass	17
	3.2.2.7	Motor Preheat	17
	3.2.2.8	Programmable Set-ups	18
	3.2.2.9	Smart Logic Control (SLC)	18
	3.2.2.9.1	Comparators	19
	3.2.2.9.2 Logic Rules		19
3.3 VLT® Compressor Drive CDS 803 Protections			19
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Design Guide				Contents
	3.3.1	Mains Input Protection		19
		3.3.1.1 Mains Supply Failure, Momentary Dropouts, and Surges		19
		3.3.1.2 Missing Mains Phase Detection		20
	3.3.2	Output Protection		20
		3.3.2.1	Short-circuit Protection (Phase-to-phase)	20
		3.3.2.2 Ground Fault Protection (Output Phase-to-Ground)		20
		3.3.2.3	Locked Rotor Detection	20
		3.3.2.4 Output Phase Loss Detection		20
		3.3.2.5	Overload Protection	20
	3.3.3	Temperature Protection		21
		3.3.3.1 Minimum and Maximum Temperature Protection		21
		3.3.3.2	Automatic Temperature Derating	21
		3.3.3.3	Temperature-controlled Fans	21
	3.3.4	Internal Protection		21
		3.3.4.1	DC Overvoltage Protection	21
		3.3.4.2	Internal Faults	21
3.4 Ecodesign for Power Drive Systems				21
	3.4.1 Losses in Mains Cabling			23
	3.4.2 Input Filters: Line Reactors and Harmonic Filters			23
	3.4.3	Drive, Input Side		24
	3.4.4	DC Link		24
	3.4.5	Drive, Output Side		25
	3.4.6 Motor Cables and Motor			26
4 Specifications				27
4.1	Electrical Data			27
	4.1.1 Electrical Data 3x200–240 V AC			27
	4.1.2 Electrical Data 3x380–480 V AC			27
4.2 Mains Supply (L1, L2, L3)				28
4.3 Compressor Output (U, V, W)				28
4.4	Control Input/Output			29
	4.4.1 10 V DC Output			29
	4.4.2 24 V DC Output			29
	4.4.3	Analog Inputs		29
	4.4.4	Analog Outputs		29
	4.4.5	Digital Inputs		29
	4.4.6	Digital Outputs		30
	4.4.7 Relay Outputs, Enclosure Sizes H3–H5			30
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Design Guide				Contents
		4.4.8 Relay Outputs, Enclosure Size H6		30
		4.4.9	RS485 Serial Communication	31
	4.5	Ambient Conditions		31
	4.6	Conforming Standards		32
	4.7	Cable Lengths and Cross-sections		32
	4.8	Acoustic Noise		32
	4.9	Mechanical Dimensions		33
		4.9.1	Drive Dimensions	33
		4.9.2	Shipping Dimensions	34
	4.10	dU/dt		34
5	Mechanical Installation Considerations			36
	5.1	Safe Transportation and Storage		36
		5.1.1	Reforming the Capacitors	36
	5.2	Side-by-side Installation		37
	5.3	Operating Environment		37
		5.3.1	Gases	38
		5.3.2	Dust	38
		5.3.3	Air Humidity	39
		5.3.4	Vibration and Shock	39
		5.3.5 Derating for Ambient Temperature and Switching Frequency		39
			5.3.5.1 Derating Curves, 6.0, 7.5, and 10 kW	39
			5.3.5.2 Derating Curves, 18.5–22 kW	40
			5.3.5.3 Derating Curves, 30 kW	40
		5.3.6 Derating for Low Air Pressure and High Altitudes		41
	5.4	IP21/NEMA Type 1 Enclosure Kit		41
	5.5	Acoustic Noise or Vibration		43
	5.6	Recommended Disposal		43
6	Electrical Installation Considerations			45
	6.1	Electrical Installation in General		45
		6.1.1	Fastener Torque Ratings	45
	6.2	Fuses and Circuit Breakers		45
		6.2.1 Recommendation of Fuses and Circuit Breakers		45
	6.3	Electrical Wiring		46
		6.3.1	Wiring Schematic	46
		6.3.2 Terminal Overview of Enclosure Sizes H3–H5		47
		6.3.3 Terminal Overview of Enclosure Size H6		48
		6.3.4 Connecting to Mains and Compressor Terminals		48
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VLT® Compressor Drive CDS 803
Design Guide				Contents
			6.3.4.1 IT Grid Installations	49
		6.3.5	Relay Terminals	49
		6.3.6	Control Terminals	50
	6.4	Setting Up RS485 Serial Communication		51
	6.5	Electromagnetic Compatibility		52
		6.5.1 EMC Emission Test Results		53
		6.5.2	Emission Requirements	53
		6.5.3	Immunity Requirements	54
		6.5.4	EMC Compatibility	56
		6.5.5	EMC-compliant Electrical Installation	57
		6.5.6	EMC-compliant Cables	59
		6.5.7	Shielded Control Cables	60
		6.5.8	RFI Filter Switch	61
	6.6	Harmonics Emission		61
		6.6.1	Harmonics Emission Requirements	62
		6.6.2 Harmonics Test Results (Emission)		62
	6.7	Galvanic Isolation (PELV)		63
	6.8	Ground Leakage Current		63
		6.8.1 Using a Residual Current Device (RCD)		65
7	How to Order			67
	7.1	Drive Configurator		67
	7.2	Type Code Description		67
	7.3	Accessories and Spare Parts		68
8	Appendix			69
	8.1	Abbreviations		69
	8.2	Conventions		69

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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.

Table 1: Manual and Software Version

Edition	Remarks	Software version
AJ330233902305, version 0201	Software update for 18–30 kW (25–40 hp) drives.	6.0–10 kW (8–15 hp): Version 2.0
		18–30 kW (25–40 hp): Version 61.20

1.4 Approvals and Certifications

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

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VLT® Compressor Drive CDS 803
Design Guide	Introduction
Description	Conformity mark

VIT-SEPRO Declaration of Conformity (VIT - All-Union Institute of Transformer Engineering)

Low Voltage Directive/Electromagnetic compatibility (EMC)

Country of use: Ukraine

089

Moroccan Declaration of Conformity (CMIM - Moroccan Conformity Mark)

Low Voltage Directive/Electromagnetic compatibility (EMC)

Country of use: Morocco

Eurasian Economic Union Declaration of Conformity (EAC - Eurasian Conformity Mark) Customs Union Technical Regulations (CU TR)

Low voltage Directive/Electromagnetic compatibility (EMC)/Restriction of Hazardous Substances Directive (RoHS)

Countries of use: Eurasian Economic Union (Russia, Belarus, Kazakhstan, Armenia, and Kirghizstan)

Certification of Compliance UL listed (UL - Underwriters Laboratories)

Safety organization

Countries of use: USA and Canada

Certification of Compliance UL recognized (UL - Underwriters Laboratories)

Safety organization

Countries of use: USA and Canada

N O T I C E

The VLT® Compressor Drive CDS 803 with SXXX in the type code is certified against UL 508C. Example: CDS803P7K5T4E20H4XXCXXXSXXXXAXBXCXXXXDX

The VLT® Compressor Drive CDS 803 with S096 in the type code is certified against UL/EN/IEC 60730-1. Example: CDS803P30KT4E20H2XXXXXXS096XAXBXCXXXXDX

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Design Guide	Safety

2 Safety

2.1 Safety Symbols

The following symbols are used in this manual:

D A N G E R

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).

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.

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Design Guide	Safety

W A R N I N G

DISCHARGE TIME

The drive contains DC-link capacitors, which can remain charged even when the drive is not powered. High voltage can be present even when the warning indicator lights are off.

Failure to wait the specified time after power has been removed before performing service or repair work could result in death or serious injury.

-Stop the motor.

-Disconnect AC mains, permanent magnet type motors, and remote DC-link supplies, including battery back-ups, UPS, and DC-link connections to other drives.

-Wait for the capacitors to discharge fully. The minimum waiting time is specified in the table Discharge time and is also visible on the nameplate on the top of the drive.

-Before performing any service or repair work, use an appropriate voltage measuring device to make sure that the capacitors are fully discharged.

Table 2: Discharge Time

Voltage [V]	Power range [kW (hp)]	Minimum waiting time (minutes)
3x200	6.0–10 (8.0–15)	15
3x400	6.0–7.5 (8.0–10)	4
3x400	10–30 (15–40)	15

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 that the minimum size of the ground conductor complies with the local safety regulations for high touch current equipment.

W A R N I N G

EQUIPMENT HAZARD

Contact with rotating shafts and electrical equipment can result in death or serious injury.

-Ensure that only trained and qualified personnel perform installation, start-up, and maintenance.

-Ensure that electrical work conforms to national and local electrical codes.

-Follow the procedures in this manual.

C A U T I O N

INTERNAL FAILURE HAZARD

An internal failure in the drive can result in serious injury when the drive is not properly closed.

-Ensure that all safety covers are in place and securely fastened before applying power.

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Design Guide	Product Overview

3 Product Overview

3.1 VLT® Compressor Drive CDS 803 Family Overview

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.

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Illustration 1: VLT® Compressor Drive CDS 803 Family

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Design Guide									Product Overview
Table 3: Overview of VLT® Compressor Drive CDS 803 Family
Power [kW]	P6K0		P7K5	P10K	P18K			P22K		P30K
Electrical
Mains voltage [V]	3x200–240		3x200–240	3x200–240	3x380–480			3x380–480		3x380–480
	3x380–480		3x380–480	3x380–480
Typical shaft output [hp]	8.0		10	15	25			30		40
Mechanical
Enclosure size	H4		H4	H5	H5			H5		H6
	H3		H3	H4
IP protection rating(1)	IP20		IP20	IP20	IP20			IP20		IP20
Compliance
RFI filter	H4 RFI filter				H2 RFI filter
	•	EN 55011 A1			•	EN 55011 A2
	•	EN/IEC 61800-3 C2			•	EN/IEC 61800-3 C3
UL rating	UL Listed				UL Recognized
	•	UL 508C			•	UL 60730-1

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.

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Design Guide	Product Overview

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	Start
	speed
		Start-up sequence
		Time
	Speed
	Compressor
	start minimum
	speed

A18, Start failed

Compressor start	Time
maximum time to trip

Illustration 2: Compressor Start-up Sequence

3.2.1.2 Compressor Minimum Speed Detection

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.

Speed

Motor speed low limit

Compressor minimum speed for trip

Minimum speed detection timer start

Illustration 3: Minimum Speed Detection

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VLT® Compressor Drive CDS 803

Design Guide	Product Overview

3.2.1.3 Short-cycle Protection

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.

Speed

Start signal

On

Off

Interval between

Starts expires Warning 96 “Start Delay”

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Time

Time

Illustration 4: Short Cycle Protection, Start Delay

Speed

Start signal

On

Off

Minimum run time expired

Warning 97

“Stop Delay”

Illustration 5: Short Cycle Protection, Stop Delay

3.2.1.4 Anti-reverse Protection

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Time

Time

The anti-reverse protection function prevents the compressor scroll set from running in the wrong direction during stop.

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Design Guide	Product Overview

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Anti-reverse
protection
	Time

Illustration 6: Anti-reverse Protection

3.2.1.5 Oil Return Management

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.

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ORM boost speed
Decrease ORM
timer
ORM Min
speed limit
	Increase ORM
Increase ORM	timer
timer
ORM low speed running time expire	ORM low speed running time starts	Time
ORM timer reset

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.

•Compressor readout of frequency in RPS.

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VLT® Compressor Drive CDS 803
Design Guide	Product Overview
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3.2.1.7 Undersized Compressor

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.

3.2.2.2 Motor Thermal Protection

Motor thermal protection can be provided via:

•Mechanical thermal switch (Klixon type) on a DI.

•Built-in electronic relay (ETR).

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Design Guide	Product Overview

N O T I C E

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.

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2000
1000
600
500
400
300
200										f OUT		= 2 x f M,N (parameter 1-23)
100
										f OUT		= 1 x f M,N
60
50										f OUT		= 0.2 x f M,N
40
30
20												IM
10
											IM,N (parameter 1-24)
	1.0		1.2 1.4 1.6 1.8 2.0

Illustration 8: ETR Characteristics

The X-axis shows the ratio between Imotor and Imotor nominal. The Y-axis shows the time in seconds before the ETR cuts off and trips 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-fre- quency 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.

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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.

Par. 13-51	Par. 13-52
SL Controller Event	SL Controller Action

Running	Coast
Warning	Start timer
Torque limit	Set Do X low
Digital input X 30/2	Select set-up 2
. . .	. . .
Par. 13-43
Logic Rule Operator 2
. . .
. . .
Par. 13-11
Comparator Operator
=
TRUE longer than..
. . .
. . .

Illustration 9: SLC Event and Action

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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:

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Start

event P13-01

	State 1
	13-51.0	State 2
	13-52.0
	Stop	13-51.1
		13-52.1
	event P13-02

Stop

State 4 13-51.3 13-52.3

event P13-02

State 3 13-51.2 13-52.2

Stop

event P13-02

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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.

	Par. 13-11
Par. 13-10	Comparator Operator
Comparator Operand
	=
Par. 13-12	TRUE longer than.
	. . .
Comparator Value
	. . .

Illustration 11: Comparators

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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.

Par. 13-41

Par. 13-43

Par. 13-40

Logic Rule Operator 1

Logic Rule Operator 2

Logic Rule Boolean 1

Par. 13-42

Logic Rule Boolean 2

. . .

. . .

. . .

. . .

Par. 13-44

Logic Rule Boolean 3

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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.

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The drive withstands mains fluctuations such as:

•Transients

•Momentary dropouts

•Short voltage drops

•Surges

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.

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.

3.3.2.2 Ground Fault Protection (Output Phase-to-Ground)

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.

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Output current limit

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 Protection.

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 disabled.

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.

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The CDM contains the drive controller as well as auxiliary devices and input components.

Motor control equipment = CDM or starter

Motor Starter

(Contactor, Softstarter,…)

Complete Drive Module (CDM)

Driven Equipment

Feeding

Auxiliaries

Basic

Mains &

section

Drive

Transmis-

Load-

cabling

Module

(BDM)

sion

Machine

Power Drive System (PDS)

Motor System

Extended Product

Illustration 13: Drive System Design

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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).

Relative torque producing current

100 %

50 %
25 %
0 %
0 %	50 %	90 %

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Relative motor stator frequency

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 calculation. 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 http://ecosmart.danfoss.com.

Refer to Illustration 15 to see the components in the PDS which contribute to losses in the design. Mains cables and the load machine 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.

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	Losses	Losses	Losses	<![if ! IE]> <![endif]>e30bh443.11
Input power	Input filters	Drive input	DC link
Drive output	Output filters	Motor		Output power
Losses	Losses	Losses

Illustration 15: Losses in a Power Drive System

3.4.1 Losses in Mains Cabling

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:

PL,mains = 3 x R x IL12

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.

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 Danfoss.com.

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-

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