Danfoss FC 111 Design guide

Design Guide

VLT® Flow Drive FC 111

vlt-drives.danfoss.com

VLT® Flow Drive FC 111
Design Guide	Contents

Contents

1 Introduction			10
1.1	Purpose of this Design Guide		10
1.2	Additional Resources		10
	1.2.1	Other Resources	10
	1.2.2 MCT 10 Set-up Software Support		10
1.3	Document and Software Version		10
1.4	Regulatory Compliance		10
	1.4.1	Introduction	10
	1.4.2	CE Mark	10

2 Safety		12
2.1	Safety Symbols	12
2.2	Qualified Personnel	12
2.3	Safety Precautions	12

3 Product Overview			14
3.1 Advantages			14
3.1.1 Why Use a Drive for Controlling Fans and Pumps?			14
	3.1.1.1 The Clear Advantage - Energy Savings		14
	3.1.1.2 Example of Energy Savings		15
	3.1.1.3 Comparison of Energy Savings		15
	3.1.1.4 Example with Varying Flow over 1 Year		17
	3.1.1.5	Better Control	18
	3.1.1.6 Star/Delta Starter or Soft Starter not Required		18
	3.1.1.7 Using a Drive Saves Money		18
	3.1.1.8 Traditional Fan System without a Drive		19
	3.1.1.9 Fan System Controlled by Drives		20
3.1.2	Application Examples		20
	3.1.2.1	Variable Air Volume	20
	3.1.2.2	Constant Air Volume	21
	3.1.2.3	Cooling Tower Fan	22
	3.1.2.4	Condenser Pumps	23
	3.1.2.5	Primary Pumps	24
	3.1.2.6	Secondary Pumps	25
3.1.3	Check Valve Monitoring		26
3.1.4	Dry Pump Detection		26
3.1.5 End of Curve Detection			26
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VLT® Flow Drive FC 111
Design Guide				Contents
	3.1.6	Time-based Functions		26
3.2	Control Structures			26
	3.2.1	Introduction		26
	3.2.2 Control Structure Open Loop			27
	3.2.3	PM/EC+ Motor Control		27
	3.2.4 Local (Hand On) and Remote (Auto On) Control			27
	3.2.5 Control Structure Closed Loop			28
	3.2.6	Feedback Conversion		28
	3.2.7	Reference Handling		28
	3.2.8 Tuning the Drive Closed-loop			29
	3.2.9 Adjusting the Manual PI			29
3.3	Ambient Running Conditions			30
	3.3.1	Air Humidity		30
	3.3.2 Acoustic Noise or Vibration			30
		3.3.2.1	Acoustic Noise	30
		3.3.2.2	Vibration and Shock	31
	3.3.3	Aggressive Environments		31
3.4 General Aspects of EMC				31
	3.4.1 Overview of EMC Emissions			31
	3.4.2	Emission Requirements		32
	3.4.3 EMC Emission Test Results			33
	3.4.4	Harmonics Emission		34
		3.4.4.1	Harmonics Emission Requirements	34
		3.4.4.2 Harmonics Test Results (Emission)		35
	3.4.5	Harmonics Emission Requirements		34
	3.4.6 Harmonics Test Results (Emission)			36
	3.4.7	Immunity Requirements		37
3.5	Galvanic Isolation (PELV)			37
3.6	Ground Leakage Current			38
	3.6.1 Using a Residual Current Device (RCD)			40
3.7	Extreme Running Conditions			41
	3.7.1	Introduction		41
	3.7.2 Motor Thermal Protection (ETR)			42
	3.7.3	Thermistor Inputs		42
		3.7.3.1 Example with Digital Input and 10 V Power Supply		43
		3.7.3.2 Example with Analog Input and 10 V Power Supply		43

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Design Guide	Contents

4 Selection and Ordering			45
4.1	Type Code		45
4.2	Options and Accessories		46
	4.2.1 Local Control Panel (LCP)		46
	4.2.2	IP21 Enclosure Kit	46
	4.2.3	Decoupling Plate	48
4.3	Ordering Numbers		49
	4.3.1	Options and Accessories	49
	4.3.2	Harmonic Filters	50
	4.3.3	External RFI Filter	51

5 Mechanical Installation Considerations			53
5.1	Power Ratings, Weights, and Dimensions		53
5.2	Mechanical Installation H1-H8		55
	5.2.1	Side-by-side Installation	55
5.3	Mechanical Installation H13-H14		56
	5.3.1	Tools Needed	56
	5.3.2 Installation and Cooling Requirements		56
	5.3.3	Lifting the Drive	57
	5.3.4 Wall Mounting the Drive		58
	5.3.5	Creating Cable Openings	59
	5.3.6	Back-channel Cooling	59
5.4	Derating		60
	5.4.1 Manual Derating and Automatic Derating		60
	5.4.2 Derating for Low-speed Operation		60
	5.4.3 Derating for Low Air Pressure and High Altitudes		60
	5.4.4 Derating for Ambient Temperature and Switching Frequency		60

6 Electrical Installation Considerations		63
6.1	Safety Instructions	63
6.2	Electrical Wiring	64
6.3	EMC-compliant Electrical Installation	64
6.4	Relays and Terminals	66
	6.4.1 Relays and Terminals on Enclosure Sizes H1–H5	66
	6.4.2 Relays and Terminals on Enclosure Size H6	67
	6.4.3 Relays and Terminals on Enclosure Size H7	67
	6.4.4 Relays and Terminals on Enclosure Size H8	68
	6.4.5 Relays and Terminals on Enclosure Size H13–H14	69
6.5	View of Control Shelf	69
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VLT® Flow Drive FC 111
Design Guide				Contents
6.6	Fastener Tightening Torques			70
6.7	IT Mains			71
6.8	Mains and Motor Connection			72
	6.8.1	Introduction		72
	6.8.2	Connecting to the Ground		72
	6.8.3	Connecting the Motor		73
	6.8.4	Connecting the AC Mains		73
6.9	Fuses and Circuit Breakers			73
	6.9.1	Branch Circuit Protection		73
	6.9.2	Short-circuit Protection		73
	6.9.3	Overcurrent Protection		74
	6.9.4	CE Compliance		74
	6.9.5	Recommendation of Fuses and Circuit Breakers		74
6.10	Control Terminals			75
6.11	Efficiency			76
	6.11.1	Efficiency of the Drive		76
	6.11.2	Efficiency of the Motor		77
	6.11.3	Efficiency of the System		77
6.12	dU/dt Conditions			77
	6.12.1	dU/dt Overview		77
	6.12.2	dU/dt Test Results for H1–H8		77
	6.12.3	High-power Range		80
	6.12.4	dU/dt Test Results for H13–H14		80
7 Programming				81
7.1	Local Control Panel (LCP)			81
7.2	Menus			82
	7.2.1	Status Menu		82
	7.2.2	Quick Menu		82
		7.2.2.1	Quick Menu Introduction	82
		7.2.2.2	Setup Wizard Introduction	83
		7.2.2.3 Setup Wizard for Open-loop Applications		84
		7.2.2.4 Setup Wizard for Closed-loop Applications		89
		7.2.2.5	Motor Setup	94
		7.2.2.6	Changes Made Function	97
		7.2.2.7	Changing Parameter Settings	98
		7.2.2.8 Accessing All Parameters via the Main Menu		98
	7.2.3	Main Menu		98
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Design Guide			Contents
7.3	Quick Transfer of Parameter Settings between Multiple Drives		98
	7.3.1	Transferring Data from the Drive to the LCP	98
	7.3.2	Transferring Data from the LCP to the Drive	98
7.4	Readout and Programming of Indexed Parameters		99
7.5	Initialization to Default Settings		99
	7.5.1	Recommended Initialization	99
	7.5.2	Two-finger Initialization	99
8 RS485 Installation and Set-up			101
8.1	RS485		101
	8.1.1	Overview	101
	8.1.2	Connecting the Drive to the RS485 Network	102
	8.1.3	Hardware Set-up	102
	8.1.4	Parameter Settings for Modbus Communication	103
	8.1.5	EMC Precautions	103
8.2	FC Protocol		104
	8.2.1	Overview	104
	8.2.2	FC with Modbus RTU	104
8.3	Network Configuration		105
8.4	FC Protocol Message Framing Structure		105
	8.4.1	Content of a Character (byte)	105
	8.4.2	Telegram Structure	105
	8.4.3	Telegram Length (LGE)	105
	8.4.4	Drive Address (ADR)	106
	8.4.5	Data Control Byte (BCC)	106
	8.4.6	The Data Field	106
	8.4.7	The PKE Field	107
	8.4.8	Parameter Number (PNU)	108
	8.4.9	Index (IND)	108
	8.4.10	Parameter Value (PWE)	108
	8.4.11	Data Types Supported by the Drive	109
	8.4.12	Conversion	109
	8.4.13	Process Words (PCD)	110
8.5	Examples		110
	8.5.1	Writing a Parameter Value	110
	8.5.2	Reading a Parameter Value	110
8.6	Modbus RTU		111
	8.6.1	Prerequisite Knowledge	111
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VLT® Flow Drive FC 111
Design Guide				Contents
	8.6.2	Modbus RTU Overview		111
	8.6.3	Drive with Modbus RTU		111
8.7	Network Configuration			112
8.8	Modbus RTU Message Framing Structure			112
	8.8.1	Modbus RTU Message Byte Format		112
	8.8.2	Modbus RTU Telegram Structure		113
	8.8.3	Start/Stop Field		113
	8.8.4	Address Field		113
	8.8.5	Function Field		113
	8.8.6	Data Field		113
	8.8.7	CRC Check Field		113
	8.8.8	Coil Register Addressing		114
		8.8.8.1	Introduction	114
		8.8.8.2	Coil Register	114
		8.8.8.3 Drive Control Word (FC Profile)		114
		8.8.8.4 Drive Status Word (FC Profile)		115
		8.8.8.5	Address/Registers	115
	8.8.9	Access via PCD Write/read		116
	8.8.10	How to Control the Drive		117
		8.8.10.1	Introduction	117
		8.8.10.2 Function Codes Supported by Modbus RTU		117
		8.8.10.3	Modbus Exception Codes	118
8.9	How to Access Parameters			118
	8.9.1	Parameter Handling		118
	8.9.2	Storage of Data		118
	8.9.3	IND (Index)		119
	8.9.4	Text Blocks		119
	8.9.5	Conversion Factor		119
	8.9.6	Parameter Values		119
8.10	Examples			119
	8.10.1	Introduction		119
	8.10.2	Read Coil Status (01 hex)		119
	8.10.3	Force/Write Single Coil (05 hex)		120
	8.10.4	Force/Write Multiple Coils (0F hex)		121
	8.10.5	Read Holding Registers (03 hex)		122
	8.10.6	Preset Single Register (06 hex)		122
	8.10.7	Preset Multiple Registers (10 hex)		123
	8.10.8	Read/Write Multiple Registers (17 hex)		124
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VLT® Flow Drive FC 111
Design Guide			Contents
8.11	Danfoss FC Control Profile		125
	8.11.1	Control Word According to FC Profile (8-10 Protocol = FC Profile)	125
	8.11.2	Explanation of Each Control Bit	126
	8.11.3	Status Word According to FC Profile (STW)	128
	8.11.4	Explanation of Each Status Bit	128
	8.11.5	Bus Speed Reference Value	130
9 General Specifications			131
9.1	Mains Supply		131
	9.1.1	3x380–480 V AC	131
9.2	General Technical Data		133
	9.2.1	Protection and Features	133
	9.2.2	Mains Supply	133
	9.2.3	Motor Output (U, V, W)	133
	9.2.4	Cable Length and Cross-section	134
	9.2.5	Digital Inputs	134
	9.2.6	Analog Inputs	134
	9.2.7	Analog Outputs	135
	9.2.8	Digital Output	135
	9.2.9	RS485 Serial Communication	135
	9.2.10	24 V DC Output	135
	9.2.11	Relay Output	135
	9.2.12	10 V DC Output	136
	9.2.13	Ambient Conditions (H1–H8)	136
	9.2.14	Ambient Conditions (H13–H14)	137
10 Appendix			138
10.1	Abbreviations		138
10.2	Definitions		139
	10.2.1	AC Drive	139
	10.2.2	Input	139
	10.2.3	Motor	139
	10.2.4	References	141
	10.2.5	Miscellaneous	141

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VLT® Flow Drive FC 111

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® Flow Drive FC 111 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 Other Resources

Other resources are available to understand advanced drive functions and programming.

•VLT® Flow Drive FC 111 Operating Guide provides basic information on mechanical dimensions, installation, and programming.

•VLT® Flow Drive FC 111 Programming Guide provides information on how to program, and includes complete parameter descriptions.

•Danfoss VLT® Energy Box software. Select PC Software Download at www.danfoss.com.

VLT® Energy Box software allows energy consumption comparisons of HVAC fans and pumps driven by Danfoss drives and alternative methods of flow control. Use this tool to accurately project the costs, savings, and payback of using Danfoss drives on HVAC fans, pumps, and cooling towers.

Supplementary publications and manuals are available from Danfoss website www.danfoss.com.

1.2.2 MCT 10 Set-up Software Support

Download the software from the service and support section on www.danfoss.com.

During the installation process of the software, enter access code 81462700 to activate the VLT® Flow Drive FC 111 functionality. A license key is not required for using the VLT® Flow Drive FC 111 functionality.

The latest software does not always contain the latest updates for drives. Contact the local sales office for the latest drive updates (in the form of *.OSS files).

1.3 Document and Software Version

This guide is regularly reviewed and updated. All suggestions for improvement are welcome. The original language of this manual is English.

Table 1: Document and Software Version

Edition	Remarks	Software version
AJ363928382091, version 0101	First edition.	65.00

1.4 Regulatory Compliance

1.4.1 Introduction

AC drives are designed in compliance with the directives described in this section.

1.4.2 CE Mark

The CE mark (Communauté Européenne) indicates that the product manufacturer conforms to all applicable EU directives. The EU directives applicable to the design and manufacture of drives are listed in the following table.

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Design Guide	Introduction

N O T I C E

The CE mark does not regulate the quality of the product. Technical specifications cannot be deduced from the CE mark.

N O T I C E

Drives with an integrated safety function must comply with the machinery directive.

Table 2: EU Directives Applicable to Drives

EU directive	Version
Low Voltage Directive	2014/35/EU
EMC Directive	2014/30/EU
ErP Directive

Declarations of conformity are available on request.

1.4.2.1 Low Voltage Directive

The aim of the Low Voltage Directive is to protect persons, domestic animals and property against dangers caused by the electrical equipment, when operating electrical equipment that is installed and maintained correctly, in its intended application. The directive applies to all electrical equipment in the 50–1000 V AC and the 75–1500 V DC voltage ranges.

1.4.2.2 EMC Directive

The purpose of the EMC (electromagnetic compatibility) Directive is to reduce electromagnetic interference and enhance immunity of electrical equipment and installations. The basic protection requirement of the EMC Directive states that devices that generate electromagnetic interference (EMI), or whose operation could be affected by EMI, must be designed to limit the generation of electromagnetic interference and shall have a suitable degree of immunity to EMI when properly installed, maintained, and used as intended. Electrical equipment devices used alone or as part of a system must bear the CE mark. Systems do not require the CE mark, but must comply with the basic protection requirements of the EMC Directive.

1.4.2.3 ErP Directive

The ErP Directive is the European Ecodesign Directive for energy-related products. The directive sets ecodesign requirements for energy-related products, including drives, and aims at reducing the energy consumption and environmental impact of products by establishing minimum energy-efficiency standards.

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VLT® Flow Drive FC 111

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 3: Discharge Time

Voltage [V]	Power range [kW (hp)]	Minimum waiting time (minutes)
3x400	0.37–7.5 (0.5–10)	4
3x400	11–90 (15–125)	15
3x400	110–315 (150–450)	20

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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VLT® Flow Drive FC 111

Design Guide	Product Overview

3 Product Overview

3.1 Advantages

3.1.1 Why Use a Drive for Controlling Fans and Pumps?

A drive takes advantage of the fact that centrifugal fans and pumps follow the laws of proportionality for such fans and pumps. For further information, see 3.1.1.2 Example of Energy Savings.

3.1.1.1 The Clear Advantage - Energy Savings

The clear advantage of using a drive for controlling the speed of fans or pumps lies in the electricity savings.

When comparing with alternative control systems and technologies, a drive is the optimum energy control system for controlling fan and pump systems.

<![if ! IE]>

<![endif]>PRESSURE%

120

A

100

80

60 B

40

C

20

SYSTEM CURVE

FAN CURVE

<![if ! IE]>

<![endif]>e30ba780.11

0	20	40	60	80	100	120	140	160	180
				VOLUME%

Illustration 1: Fan Curves (A, B, and C) for Reduced Fan Volumes

	120
													A
	100
																		SYSTEM				CURVE
<![if ! IE]> <![endif]>%	80
<![if ! IE]> <![endif]>PRESSURE	60										B										FAN	CURVE
	40
									C
	20
	0
																		140					180
			20		40		60		80		100			120							160
									Volume %
	120
<![if ! IE]> <![endif]>%	100
	60
<![if ! IE]> <![endif]>POWER
<![if ! IE]> <![endif]>INPUT	80
	40
	20			ENERGY
				CONSUMED
	0
			20		40		60		80		100			120				140			160		180
									Volume %

Illustration 2: Energy Savings with Drive Solution

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VLT® Flow Drive FC 111

Design Guide	Product Overview

When using a drive to reduce fan capacity to 60% - more than 50% energy savings may be obtained in typical applications.

3.1.1.2 Example of Energy Savings

As shown in the following illustration, the flow is controlled by changing the RPM. By reducing the speed by only 20% from the rated speed, the flow is also reduced by 20%. This is because the flow is directly proportional to the RPM. The consumption of electricity, however, is reduced by 50%.

If the system in question only needs to be able to supply a flow that corresponds to 100% a few days in a year, while the average is below 80% of the rated flow for the remainder of the year, the amount of energy saved is even more than 50%.

The following illustration describes the dependence of flow, pressure, and power consumption on RPM.

100%			<![if ! IE]> <![endif]>e75ha208.10
80%
50%	Flow ~n
		Pressure ~n2
25%
12,5%		Power ~n3
			n
	50%	80%	100%

Illustration 3: Laws of Proportionally

Flow :

Q1

=

n1

Q

n

2

2

Pressure :

H1

=

n1 2

H

2

n

2

Power :

P1

=

n1 3

P

n

2

2

Table 4: The Laws of Proportionality

Q = Flow

P = Power

Q1 = Rated flow

P1 = Rated power

Q2 = Reduced flow

P2 = Reduced power

H = Pressure

n = Speed control

H1 = Rated pressure

n1 = Rated speed

H2 = Reduced pressure

n2 = Reduced speed

3.1.1.3 Comparison of Energy Savings

The Danfoss drive solution offers major savings compared with traditional energy saving solutions such as discharge damper solution and inlet guide vanes (IGV) solution. This is because the drive is able to control fan speed according to thermal load on the system, and the drive has a built-in facility that enables the drive to function as a building management system, BMS.

The illustration in 3.1.1.2 Example of Energy Savings shows typical energy savings obtainable with 3 well-known solutions when fan volume is reduced to 60%. As the graph shows, more than 50% energy savings can be achieved in typical applications.

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VLT® Flow Drive FC 111
Design Guide	Product Overview
	<![if ! IE]> <![endif]>e30ba782.10

1

2

3

4

5

Illustration 4: The 3 Common Energy Saving Systems

1Discharge damper

2Less energy savings

3Maximum energy savings

100			Discharge Damper Solution
80						IGV Solution
<![if ! IE]> <![endif]>Inputpower %			<![if ! IE]> <![endif]>consumedEnergy
						<![if ! IE]> <![endif]>consumed
60
40						<![if ! IE]> <![endif]>Energy
20
0
0			60	0		60

Volume %

Illustration 5: Energy Savings

4IGV

5Costlier installation

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VLT Solution

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0 60

Discharge dampers reduce power consumption. Inlet guide vanes offer a 40% reduction, but are expensive to install. The Danfoss drive solution reduces energy consumption with more than 50% and is easy to install. It also reduces noise, mechanical stress, and wear-and-tear, and extends the life span of the entire application.

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VLT® Flow Drive FC 111

Design Guide	Product Overview

3.1.1.4 Example with Varying Flow over 1 Year

This example is calculated based on pump characteristics obtained from a pump datasheet. The result obtained shows energy savings of more than 50% at the given flow distribution over a year. The payback period depends on the price per kWh and the price of drive. In this example, it is less than a year when compared with valves and constant speed.

Energy savings

Pshaft = Pshaft output

[h] t 2000

1500

1000

500

										Q
100			200		300			400
									[m3 /h]

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Illustration 6: Flow Distribution over 1 Year

(mwg) Hs

60

50 B

40

30

20

10

0

(kW) Pshaft

60

50

40

30

20

10

0

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					A	1650rpm
				1350rpm
	C			1050rpm
		750rpm
						400 (m3 /h)
100		200		300

					A1	1650rpm
	B1			1350rpm
C1		1050rpm
	750rpm
100		200		300		400 (m3 /h)

Illustration 7: Energy

Table 5: Result

m3/h	Distribution		Valve regulation		Drive control
	%	Hours	Power	Consumption	Power	Consumption
			A1 - B1	kWh	A1 - C1	kWh
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VLT® Flow Drive FC 111
Design Guide						Product Overview
350	5	438	42.5	18.615	42.5	18.615
300	15	1314	38.5	50.589	29.0	38.106
250	20	1752	35.0	61.320	18.5	32.412
200	20	1752	31.5	55.188	11.5	20.148
150	20	1752	28.0	49.056	6.5	11.388
100	20	1752	23.0	40.296	3.5	6.132
Σ	100	8760	–	275.064	–	26.801

3.1.1.5 Better Control

If a drive is used for controlling the flow or pressure of a system, improved control is obtained.

A drive can vary the speed of the fan or pump, obtaining variable control of flow and pressure. Furthermore, a drive can quickly adapt the speed of the fan or pump to new flow or pressure conditions in the system.

Simple control of process (flow, level, or pressure) utilizing the built-in PI control.

3.1.1.6 Star/Delta Starter or Soft Starter not Required

When larger motors are started, it is necessary in many countries to use equipment that limits the start-up current. In more traditional systems, a star/delta starter or soft starter is widely used. Such motor starters are not required if a drive is used.

As shown in the following illustration, a drive does not consume more than rated current.

	800
	700
	600
<![if ! IE]> <![endif]>curent	500
	400
<![if ! IE]> <![endif]>load	300
<![if ! IE]> <![endif]>% Full
	200
	100						1
	0
	0				12,5		25

Illustration 8: Start-up Current

1VLT® Flow Drive FC 111

2Star/delta starter

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4

3

2

37,5 50Hz

Full load & speed

3	Soft starter
4	Start directly on mains

3.1.1.7 Using a Drive Saves Money

The example in 3.1.1.8 Traditional Fan System without a Drive and 3.1.1.9 Fan System Controlled by Drives shows that a drive replaces other equipment. It is possible to calculate the cost of installing the 2 different systems. In the example, the 2 systems can be established at roughly the same price.

Use the VLT® Energy Box software that is introduced in chapter Additional Resources to calculate the cost savings that can be achieved by using a drive.

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VLT® Flow Drive FC 111

Design Guide	Product Overview

3.1.1.8 Traditional Fan System without a Drive

Cooling section	Heating section	Inlet guide vane	Fan section
			Supply
			air
			Fan	V.A.V
-	+		M
			Sensors	outlets
			PT

Return	Flow		Return	Flow			Control
			Control
	3-Port			3-Port
	valve		Valve	valve			Valve	Mechanical
	Bypass		posi-	Bypass			posi-	linkage
			tion				tion	and vanes
								x6
								IGV
	M	Pump		M	Pump			Motor		Duct
								or
	x6			x6				actuator
										Local	Main
										D.D.C.
											B.M.S
	Starter			Starter				Starter		control
								Control
		Fuses				Fuses
											Temperature
			LV				LV				control
									Pressure		signal
			supply				supply	Power			0/10V
P.F.C							P.F.C		control
								Factor	signal
								Correction	0/10V
	Mains			Mains				Mains

Illustration 9: Traditional Fan System without a Drive

D.D.C.	Direct digital control	Sensor	Pressure
E.M.S.	Energy management system	P
V.A.V.	Variable air volume	Sensor	Temperature
		T

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VLT® Flow Drive FC 111

Design Guide	Product Overview

3.1.1.9 Fan System Controlled by Drives

Cooling section Heating section Fan section

					Supply
				Fan	air
	-		+			V.A.V
				M	Sensors
						outlets
					PT
Return	Flow	Return		Flow

			x3
M	Pump	M	Pump	Duct
x3		x3
				Local	Main
VLT		VLT	VLT	D.D.C.
					B.M.S
			Pressure	control
			control
			0-10V
			or
			0/4-20mA
	Control		Control
			temperature
	temperature
			0-10V
	0-10V
			or
	or
			0/4-20mA
	0/4-20mA
Mains		Mains	Mains

Illustration 10: Fan System Controlled by Drives

D.D.C.	Direct digital control	Sensor	Pressure
E.M.S.	Energy management system	P
V.A.V.	Variable air volume	Sensor	Temperature
		T

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3.1.2 Application Examples

The following sections give typical examples of applications.

3.1.2.1 Variable Air Volume

VAV or variable air volume systems, control both the ventilation and temperature to satisfy the requirements of a building. Central VAV systems are considered to be the most energy efficient method to air condition buildings. By designing central systems instead of distributed systems, a greater efficiency can be obtained.

The efficiency comes from utilizing larger fans and larger chillers which have much higher efficiencies than small motors and distributed air-cooled chillers. Savings are also seen from the decreased maintenance requirements.

The VLT Solution

While dampers and IGVs work to maintain a constant pressure in the ductwork, a drive solution saves much more energy and reduces the complexity of the installation. Instead of creating an artificial pressure drop or causing a decrease in fan efficiency, the drive decreases the speed of the fan to provide the flow and pressure required by the system.

Centrifugal devices such as fans behave according to the centrifugal laws. This means that the fans decrease the pressure and flow they produce as their speed is reduced. Their power consumption is thereby significantly reduced. The PI controller of the drive can be used to eliminate the need for additional controllers.

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VLT® Flow Drive FC 111

Design Guide

Pressure

Cooling coil

Heating coil

Drive

signal

Filter

Supply fan

D1

3

Pressure Flow transmitter

D2

Drive

			Return fan					Flow
					3

D3

Product Overview

VAV boxes

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T

Illustration 11: Variable Air Volume

3.1.2.2 Constant Air Volume

CAV, or constant air volume systems, are central ventilation systems usually used to supply large common zones with the minimum amounts of fresh tempered air. They preceded VAV systems and are therefore found in older multi-zoned commercial buildings as well. These systems preheat amounts of fresh air utilizing air handling units (AHUs) with a heating coil, and many are also used to air condition buildings and have a cooling coil. Fan coil units are frequently used to assist in the heating and cooling requirements in the individual zones.

The VLT Solution

With a drive, significant energy savings can be obtained while maintaining decent control of the building. Temperature sensors or CO2 sensors can be used as feedback signals to drives. Whether controlling temperature, air quality, or both, a CAV system can be controlled to operate based on actual building conditions. As the number of people in the controlled area decreases, the need for fresh air decreases. The CO2 sensor detects lower levels and decreases the supply fans speed. The return fan modulates to maintain a static pressure setpoint or fixed difference between the supply and return airflows.

With temperature control, especially used in air conditioning systems, as the outside temperature varies as well as the number of people in the controlled zone changes, different cooling requirements exist. As the temperature decreases below the setpoint, the supply fan can decrease its speed. The return fan modulates to maintain a static pressure setpoint. By decreasing the air flow, energy used to heat or cool the fresh air is also reduced, adding further savings.

Several features of the Danfoss dedicated drive can be utilized to improve the performance of the CAV system. One concern of controlling a ventilation system is poor air quality. The programmable minimum frequency can be set to maintain a minimum amount of supply air regardless of the feedback or reference signal. The drive also includes a PI controller, which allows monitoring both temperature and air quality. Even if the temperature requirement is fulfilled, the drive maintains enough supply air to satisfy the air quality sensor. The controller is capable of monitoring and comparing 2 feedback signals to control the return fan by maintaining a fixed differential airflow between the supply and return ducts as well.

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VLT® Flow Drive FC 111
Design Guide				Product Overview
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			signal
		Filter
			Supply fan
D1
				Temperature
				transmitter
D2			Pressure
			signal
		Drive	Return fan
D3				Pressure
				transmitter

Illustration 12: Constant Air Volume

3.1.2.3 Cooling Tower Fan

Cooling tower fans cool condenser-water in water-cooled chiller systems. Water-cooled chillers provide the most efficient means of creating chilled water. They are as much as 20% more efficient than air cooled chillers. Depending on climate, cooling towers are often the most energy efficient method of cooling the condenser-water from chillers.

They cool the condenser water by evaporation. The condenser water is sprayed into the cooling tower until the cooling towers fill to increase its surface area. The tower fan blows air through the fill and sprayed water to aid in the evaporation. Evaporation removes energy from the water dropping its temperature. The cooled water collects in the cooling towers basin where it is pumped back into the chillers condenser and the cycle is repeated.

The VLT Solution

With a drive, the cooling towers fans can be controlled to the required speed to maintain the condenser-water temperature. The drives can also be used to turn the fan on and off as needed.

Several features of the Danfoss dedicated drive can be utilized to improve the performance of cooling tower fans applications. As the cooling tower fans drop below a certain speed, the effect the fan has on cooling the water becomes small. Also, when utilizing a gearbox to frequency control the tower fan, a minimum speed of 40–50% is required.

The customer programmable minimum frequency setting is available to maintain this minimum frequency even as the feedback or speed reference calls for lower speeds.

Also as a standard feature, the drive can be programmed to enter a sleep mode and stop the fan until a higher speed is required. Additionally, some cooling tower fans have undesirable frequencies that may cause vibrations. These frequencies can easily be avoided by programming the bypass frequency ranges in the drive.

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VLT® Flow Drive FC 111
Design Guide				Product Overview
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			Drive

Water Inlet

		Temperature
		Sensor
BASIN	Water Outlet	Conderser
		Water pump
		<![if ! IE]> <![endif]>CHILLER

Supply

Illustration 13: Cooling Tower Fan

3.1.2.4 Condenser Pumps

Condenser water pumps are primarily used to circulate water through the condenser section of water cooled chillers and their associated cooling tower. The condenser water absorbs the heat from the chiller's condenser section and releases it into the atmosphere in the cooling tower. These systems are used to provide the most efficient means of creating chilled water, they are as much as 20% more efficient than air cooled chillers.

The VLT Solution

Drives can be added to condenser water pumps instead of balancing the pumps with a throttling valve or trimming the pump impeller.

Using a drive instead of a throttling valve simply saves the energy that would have been absorbed by the valve. This can amount to savings of 15–20% or more. Trimming the pump impeller is irreversible, thus if the conditions change and higher flow is required the impeller must be replaced.

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VLT® Flow Drive FC 111

Design Guide	Product Overview

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	Drive
	Water
	Inlet
	Flow or pressure sensor
	BASIN
	Water	<![if ! IE]> <![endif]>CHILLER
	Outlet
		Throttling
	Condenser	valve
	Water pump
		Supply

Illustration 14: Condenser Pumps

3.1.2.5 Primary Pumps

Primary pumps in a primary/secondary pumping system can be used to maintain a constant flow through devices that encounter operation or control difficulties when exposed to variable flow. The primary/secondary pumping technique decouples the primary production loop from the secondary distribution loop. This allows devices such as chillers to obtain constant design flow and operate properly while allowing the rest of the system to vary in flow.

As the evaporator flow rate decreases in a chiller, the chilled water begins to become overchilled. As this happens, the chiller attempts to decrease its cooling capacity. If the flow rate drops far enough, or too quickly, the chiller cannot shed its load sufficiently and the chiller’s safety trips the chiller requiring a manual reset. This situation is common in large installations especially when 2 or more chillers in parallel are installed if primary/ secondary pumping is not utilized.

The VLT Solution

Depending on the size of the system and the size of the primary loop, the energy consumption of the primary loop can become substantial.

A drive can be added to the primary system to replace the throttling valve and/or trimming of the impellers, leading to reduced operating expenses. 2 control methods are common:

Flow meter

Because the desired flow rate is known and is constant, a flow meter installed at the discharge of each chiller, can be used to control the pump directly. Using the built-in PI controller, the drive always maintains the appropriate flow rate, even compensating for the changing resistance in the primary piping loop as chillers and their pumps are staged on and off.

Local speed determination

The operator simply decreases the output frequency until the design flow rate is achieved.

Using a drive to decrease the pump speed is very similar to trimming the pump impeller, except it does not require any labor, and the pump efficiency remains higher. The balancing contractor simply decreases the speed of the pump until the proper flow rate is achieved and leaves the speed fixed. The pump operates at this speed any time the chiller is staged on. Because the primary loop does not have control valves or other devices that can cause the system curve to change, and the variance due to staging pumps and chillers on and off is usually small, this fixed speed remains appropriate. If the flow rate needs to be increased later in the system’s life, the drive can simply increase the pump speed instead of requiring a new pump impeller.

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VLT® Flow Drive FC 111

Design Guide

Flowmeter				Flowmeter
		F					F

<![if ! IE]> <![endif]>CHILLER

<![if ! IE]> <![endif]>CHILLER

Drive						Drive

Product Overview

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Illustration 15: Primary Pumps

3.1.2.6 Secondary Pumps

Secondary pumps in a primary/secondary chilled water pumping system distribute the chilled water to the loads from the primary production loop. The primary/secondary pumping system is used to hydronically de-couple 1 piping loop from another. In this case, the primary pump is used to maintain a constant flow through the chillers while allowing the secondary pumps to vary in flow, increase control and save energy.

If the primary/secondary concept is not used in the design of a variable volume system when the flow rate drops far enough or too quickly, the chiller cannot shed its load properly. The chiller’s low evaporator temperature safety then trips the chiller requiring a manual reset. This situation is common in large installations especially when 2 or more chillers in parallel are installed.

The VLT Solution

While the primary-secondary system with 2-way valves improves energy savings and eases system control problems, the true energy savings and control potential is realized by adding drives.

With the proper sensor location, the addition of drives allows the pumps to vary their speed to follow the system curve instead of the pump curve. This results in the elimination of wasted energy and eliminates most of the overpressurization that 2-way valves can be subjected to.

As the monitored loads are reached, the 2-way valves close down. This increases the differential pressure measured across the load and the 2-way valve. As this differential pressure starts to rise, the pump is slowed to maintain the control head also called setpoint value. This setpoint value is calculated by summing the pressure drop of the load and the 2-way valve together under design conditions.

N O T I C E

When running multiple pumps in parallel, they must run at the same speed to maximize energy savings, either with individual dedicated drives or 1 drive running multiple pumps in parallel.

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VLT® Flow Drive FC 111

Design Guide	Product Overview

			P	<![if ! IE]> <![endif]>e30bb454.10
		Drive
		3
<![if ! IE]> <![endif]>CHILLER	<![if ! IE]> <![endif]>CHILLER	3
		Drive

Illustration 16: Secondary Pumps

3.1.3 Check Valve Monitoring

In the pump application system, a damaged check valve is hard to detect, which therefore causes low efficiency of the whole system. VLT® Flow Drive FC 111 has the ability to monitor the status of check valves in the system. After enabling the check valve monitoring function via setting the parameter 22-04 Check Valve Monitor to [1] Enabled, once a damaged check valve is detected, the drive trips warning 159, Check Valve Failure.

3.1.4 Dry Pump Detection

In the pump application system, the drive monitors the operation status of the system to detect whether there is water on pump's suction side. If the pump runs at maximum speed and consumes little power, then it can be assumed that there is no water on the pump's suction side. Via setting the parameter 22-26 Dry Pump Function to warning or alarm, once the dry pump condition is detected, the drive trips warning/alarm 93, dry pump.

3.1.5 End of Curve Detection

In the pump application system, the drive monitors the operation status of the system to detect whether the pressure side of pump is subject to a major leakage. If the pump runs at maximum speed for a defined time period, but the pressure is below the set point, then it can be considered to reflect the end of curve situation. Via setting the parameter 22-50 End of Curve Function to warning or alarm, once the end of curve condition is detected, the drive trips warning/alarm 94, end of curve.

3.1.6 Time-based Functions

In some application scenarios, there are requirements to control the motor running for a specific time, in a specific direction and a specific speed within a specific time interval. For example, checking the motor status in fire mode or exercising pumps, fans, and compressors.

For detailed parameter settings, refer to the parameter group 23-** Time-based Functions in the drive's Programming Guide.

3.2 Control Structures

3.2.1 Introduction

There are two control modes for the drive:

•Open loop.

•Closed loop.

Select [0] Open loop or [1] Closed loop in parameter 1-00 Configuration Mode.

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VLT® Flow Drive FC 111

Design Guide	Product Overview

3.2.2 Control Structure Open Loop

Reference
handling								P 4-14
Remote								Motor speed
reference				Remote				high limit [Hz]
Auto mode							Reference
Hand mode				Local
Local								P 4-12
reference
								Motor speed
scaled to								low limit [Hz]
Hz
LCP Hand on,
off and auto
on keys

P 3-4* Ramp 1

P 3-5* Ramp 2

Ramp

100%	<![if ! IE]> <![endif]>e30bb892.11
0%	To motor
	control

100%
-100%				P 4-10
				Motor speed
				direction

Illustration 17: Open-loop Structure

In the configuration shown in the above illustration, parameter 1-00 Configuration Mode is set to [0] Open loop. The resulting reference from the reference handling system or the local reference is received and fed through the ramp limitation and speed limitation before being sent to the motor control. The output from the motor control is then limited by the maximum frequency limit.

3.2.3 PM/EC+ Motor Control

The Danfoss EC+ concept provides the possibility for using high-efficient PM motors (permanent magnet motors) in IEC standard enclosure sizes operated by Danfoss drives.

The commissioning procedure is comparable to the existing one for asynchronous (induction) motors by utilizing the Danfoss VVC+ PM control strategy.

Customer advantages:

•Free choice of motor technology (permanent magnet or induction motor).

•Installation and operation as know on induction motors.

•Manufacturer independent when selecting system components (for example, motors).

•Best system efficiency by selecting best components.

•Possible retrofit of existing installations.

•Power range: 0.37–90 kW (0.5–121 hp) (400 V) for induction motors and 0.37–22 kW (0.5–30 hp) (400 V) for PM motors. Current limitations for PM motors:

•Currently only supported up to 22 kW (30 hp).

•LC filters are not supported with PM motors.

•Kinetic back-up algorithm is not supported with PM motors.

•Support only complete AMA of the stator resistance Rs in the system.

•No stall detection (supported from software version 62.80).

3.2.4 Local (Hand On) and Remote (Auto On) Control

The drive can be operated manually via the local control panel (LCP) or remotely via analog/digital inputs or serial bus. If allowed in parameter 0-40 [Hand on] Key on LCP, parameter 0-44 [Off/Reset] Key on LCP, and parameter 0-42 [Auto on] Key on LCP, it is possible to start and stop the drive via LCP by pressing [Hand On] and [Off/Reset]. Alarms can be reset via the [Off/Reset] key.

Hand	Off	Auto
On	Reset	On

Illustration 18: LCP Keys

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Local reference forces the configuration mode to open loop, independent on the setting of parameter 1-00 Configuration Mode.

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VLT® Flow Drive FC 111

Design Guide	Product Overview

Local reference is restored at power-down.

3.2.5 Control Structure Closed Loop

The internal controller allows the drive to become a part of the controlled system. The drive receives a feedback signal from a sensor in the system. It then compares this feedback to a setpoint reference value and determines the error, if any, between these 2 signals. It then adjusts the speed of the motor to correct this error.

For example, consider a compressor application where the speed of the compressor is to be controlled to ensure a constant suction pressure in an evaporator. The suction pressure value is supplied to the drive as the setpoint reference. A pressure sensor measures the actual suction pressure in the evaporator and supplies the data to the drive as a feedback signal. If the feedback signal is greater than the setpoint reference, the drive speeds up the compressor to reduce the pressure. In a similar way, if the suction pressure is lower than the setpoint reference, the drive automatically slows down the compressor to increase the pressure.

		100%
Reference	+	0%
	S
	_	PI
	*[-1]	100%
Feedback
	7-30 PI	-100%	P 4-10
	Normal/Inverse		Motor speed
	Control		direction

Illustration 19: Control Structure Closed Loop

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Scale to		To motor
speed		control

While the default values for the closed-loop controller of the drive often provide satisfactory performance, the control of the system can often be optimized by adjusting parameters.

3.2.6 Feedback Conversion

In some applications, it may be useful to convert the feedback signal. One example of this is using a pressure signal to provide flow feedback. Since the square root of pressure is proportional to flow, the square root of the pressure signal yields a value proportional to the flow. See the following illustration.

Ref.				<![if ! IE]> <![endif]>e30bb895.10
signal
	Ref.+		PI
	P 20-01	-
Desired	FB conversion
flow			FB	P
			Flow	Flow
	FB			P
	signal
			P

Illustration 20: Feedback Signal Conversion

3.2.7 Reference Handling

Details for open-loop and closed-loop operation.

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VLT® Flow Drive FC 111

Design Guide	Product Overview

Intern resource

Relative scalling reference

Preset relative reference

±100%

Input command:

Preset reference 0 ±100%

preset ref bit0, bit1, bit2

Preset reference 1 ±100%

Preset reference 2 ±100%

Preset reference 3 ±100%

Preset reference 4 ±100%

Preset reference

Preset reference 5 ±100%

Preset reference 6 ±100%

±100%

Preset reference 7 ±100%

Y

Relative

External resource 1

reference

Parameter choise:

+

X

=

No function

X+X*Y/100

Reference resource 1,2,3

±200%

Analog reference

±200 %

Local bus reference

±200 %

Pulse input reference

±200 %

+

External resource 2

No function

±200%

Analog reference

±200 %

Local bus reference

±200 %

Pulse input reference

±200 %

External resource 3

External reference in %

No function

Analog reference

±200 %

Local bus reference

±200 %

Pulse input reference

±200 %

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		Speed open
		loop
Input command:	mode	Scale to
		Hz
freeze reference

			Remote
		maxRefPCT	reference/
			setpoint
	±200%	minRefPct
			Process
		min-max ref
	±100%		control

	Freeze
	reference &
	increase/
	decrease
	reference				Scale to
					process
Input commands:					unit
Speed up/speed down

±200% Feedback handling

Remote reference in %

Illustration 21: Block Diagram Showing Remote Reference

The remote reference consists of:

•Preset references.

•External references (analog inputs and serial communication bus references).

•The preset relative reference.

•Feedback-controlled setpoint.

Up to 8 preset references can be programmed in the drive. The active preset reference can be selected using digital inputs or the serial communications bus. The reference can also be supplied externally, most commonly from an analog input. This external source is selected by 1 of the 3 reference source parameters (parameter 3-15 Reference 1 Source, parameter 3-16 Reference 2 Source, and parameter 3-17 Reference 3 Source). All reference resources and the bus reference are added to produce the total external reference. The external reference, the preset reference, or the sum of the 2 can be selected to be the active reference. Finally, this reference can by be scaled using parameter 3-14 Preset Relative Reference.

The scaled reference is calculated as follows:

Reference = X + X × Y

100

Where X is the external reference, the preset reference or the sum of these and Y is parameter 3-14 Preset Relative Reference in [%]. If Y, parameter 3-14 Preset Relative Reference, is set to 0%, the reference is not affected by the scaling.

3.2.8 Tuning the Drive Closed-loop

Once the drive's closed-loop controller has been set up, test the performance of the controller. Often, its performance may be acceptable using the default values of parameter 20-93 PI Proportional Gain and parameter 20-94 PI Integral Time. However, sometimes it may be helpful to optimize these parameter values to provide faster system response while still controlling speed overshoot.

3.2.9 Adjusting the Manual PI

Procedure

1.Start the motor.

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VLT® Flow Drive FC 111

Design Guide	Product Overview

2.Set parameter 20-93 PI Proportional Gain to 0.3 and increase it until the feedback signal begins to oscillate. If necessary, start and stop the drive or make step changes in the setpoint reference to attempt to cause oscillation.

3.Reduce the PI proportional gain until the feedback signal stabilizes.

4.Reduce the proportional gain by 40–60%.

5.Set parameter 20-94 PI Integral Time to 20 s and reduce it until the feedback signal begins to oscillate. If necessary, start and stop the drive or make step changes in the setpoint reference to attempt to cause oscillation.

6.Increase the PI integral time until the feedback signal stabilizes.

7.Increase the integral time by 15–50%.

3.3Ambient Running Conditions

3.3.1 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).

3.3.2 Acoustic Noise or Vibration

If the motor or the equipment driven by the motor - for example, a fan - makes noise or vibrations at certain frequencies, configure the following parameters or parameter groups to reduce or eliminate the noise or vibrations:

•Parameter group 4-6* Speed Bypass.

•Set parameter 14-03 Overmodulation to [0] Off.

•Switching pattern and switching frequency parameter group 14-0* Inverter Switching.

•Parameter 1-64 Resonance Dampening.

3.3.2.1 Acoustic Noise

The acoustic noise from the drive comes from 3 sources:

•DC-link coils.

•Integral fan.

•RFI filter choke.

Table 6: Typical Values Measured at a Distance of 1 m (3.28 ft) from the Unit

Enclosure size		Level [dBA](1)
H1		43.6
H2		50.2
H3		53.8
H4		64
H5		63.7
H6		71.5
H7		67.5 (75 kW (100 hp) 71.5 dB)
H8		73.5
H13		73
H14		75

1 The values are measured under the background of 35 dBA noise and the fan running with full speed.

30 | Danfoss A/S © 2021.04

AJ363928382091en-000101 / 130R0983