Danfoss FC 101 Design guide

ENGINEERING TOMORROW

Design Guide

VLT® HVAC Basic Drive FC 101

vlt-drives.danfoss.com

Contents	Design Guide

Contents

1 Introduction	6
1.1 Purpose of the Design Guide	6
1.2 Document and Software Version	6
1.3 Safety Symbols	6
1.4 Abbreviations	7
1.5 Additional Resources	7
1.6 De€nitions	7
1.7 Power Factor	9
1.8 Regulatory Compliance	10
1.8.1 CE Mark	10
1.8.2 UL Compliance	10
1.8.3 RCM Mark Compliance	10
1.8.4 EAC	11
1.8.5 UkrSEPRO	11
2 Safety	12
2.1 Quali€ed Personnel	12
2.2 Safety Precautions	12
3 Product Overview	14
3.1 Advantages	14
3.1.1 Why use a Frequency Converter for Controlling Fans and Pumps?	14
3.1.2 The Clear Advantage - Energy Savings	14
3.1.3 Example of Energy Savings	14
3.1.4 Comparison of Energy Savings	15
3.1.5 Example with Varying Flow over 1 Year	16
3.1.6 Better Control	16
3.1.7 Star/Delta Starter or Soft Starter not Required	17
3.1.8 Using a Frequency Converter Saves Money	17
3.1.9 Without a Frequency Converter	18
3.1.10 With a Frequency Converter	19
3.1.11 Application Examples	19
3.1.12 Variable Air Volume	19
3.1.13 The VLT Solution	20
3.1.14 Constant Air Volume	21
3.1.15 The VLT Solution	21
3.1.16 Cooling Tower Fan	22
3.1.17 The VLT Solution	22
3.1.18 Condenser Pumps	23
3.1.19 The VLT Solution	23

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

1

Contents

VLT® HVAC Basic Drive FC 101

3.1.20 Primary Pumps	24
3.1.21 The VLT Solution	24
3.1.22 Secondary Pumps	26
3.1.23 The VLT Solution	26
3.2 Control Structures	27
3.2.1 Control Structure Open Loop	27
3.2.2 PM/EC+ Motor Control	27
3.2.3 Local (Hand On) and Remote (Auto On) Control	27
3.2.4 Control Structure Closed Loop	28
3.2.5 Feedback Conversion	28
3.2.6 Reference Handling	29
3.2.7 Tuning the Drive Closed-loop Controller	30
3.2.8 Manual PI Adjustment	30
3.3 Ambient Running Conditions	30
3.4 General Aspects of EMC	36
3.4.1 Overview of EMC Emissions	36
3.4.2 Emission Requirements	38
3.4.3 EMC Emission Test Results	39
3.4.4 Overview of Harmonics Emission	41
3.4.5 Harmonics Emission Requirements	41
3.4.6 Harmonics Test Results (Emission)	41
3.4.7 Immunity Requirements	43
3.5 Galvanic Isolation (PELV)	43
3.6 Earth Leakage Current	44
3.7 Extreme Running Conditions	44
3.7.1 Motor Thermal Protection (ETR)	44
3.7.2 Thermistor Inputs	45

4 Selection and Ordering	47
4.1 Type Code	47
4.2 Options and Accessories	48
4.2.1 Local Control Panel (LCP)	48
4.2.2 Mounting of LCP in Panel Front	48
4.2.3 IP21/NEMA Type 1 Enclosure Kit	49
4.2.4 Decoupling Plate	51
4.3 Ordering Numbers	51
4.3.1 Options and Accessories	51
4.3.2 Harmonic Filters	52
4.3.3 External RFI Filter	54
5 Installation	55

2

Danfoss A/S © 04/2018 All rights reserved.

MG18C802

Contents	Design Guide

5.1 Electrical Installation	55
5.1.1 Mains and Motor Connection	57
5.1.2 EMC-compliant Electrical Installation	62
5.1.3 Control Terminals	64

6 Programming	65
6.1 Introduction	65
6.2 Local Control Panel (LCP)	65
6.3 Menus	66
6.3.1 Status Menu	66
6.3.2 Quick Menu	66
6.3.3 Main Menu	80
6.4 Quick Transfer of Parameter Settings between Multiple Frequency Converters	80
6.5 Readout and Programming of Indexed Parameters	81
6.6 Initialization to Default Settings	81
7 RS485 Installation and Set-up	82
7.1 RS485	82
7.1.1 Overview	82
7.1.2 Network Connection	82
7.1.3 Frequency Converter Hardware Set-up	82
7.1.4 Parameter Settings for Modbus Communication	83
7.1.5 EMC Precautions	83
7.2 FC Protocol	84
7.2.1 Overview	84
7.2.2 FC with Modbus RTU	84
7.3 Parameter Settings to Enable the Protocol	84
7.4 FC Protocol Message Framing Structure	84
7.4.1 Content of a Character (Byte)	84
7.4.2 Telegram Structure	84
7.4.3 Telegram Length (LGE)	85
7.4.4 Frequency Converter Address (ADR)	85
7.4.5 Data Control Byte (BCC)	85
7.4.6 The Data Field	85
7.4.7 The PKE Field	85
7.4.8 Parameter Number (PNU)	86
7.4.9 Index (IND)	86
7.4.10 Parameter Value (PWE)	86
7.4.11 Data Types Supported by the Frequency Converter	87
7.4.12 Conversion	87
7.4.13 Process Words (PCD)	87

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

3

Contents

VLT® HVAC Basic Drive FC 101

7.5 Examples	87
7.5.1 Writing a Parameter Value	87
7.5.2 Reading a Parameter Value	88
7.6 Modbus RTU Overview	88
7.6.1 Introduction	88
7.6.2 Overview	88
7.6.3 Frequency Converter with Modbus RTU	89
7.7 Network Con€guration	89
7.8 Modbus RTU Message Framing Structure	89
7.8.1 Introduction	89
7.8.2 Modbus RTU Telegram Structure	89
7.8.3 Start/Stop Field	90
7.8.4 Address Field	90
7.8.5 Function Field	90
7.8.6 Data Field	90
7.8.7 CRC Check Field	90
7.8.8 Coil Register Addressing	90
7.8.9 Access via PCD write/read	92
7.8.10 How to Control the Frequency Converter	93
7.8.11 Function Codes Supported by Modbus RTU	93
7.8.12 Modbus Exception Codes	93
7.9 How to Access Parameters	94
7.9.1 Parameter Handling	94
7.9.2 Storage of Data	94
7.9.3 IND (Index)	94
7.9.4 Text Blocks	94
7.9.5 Conversion Factor	94
7.9.6 Parameter Values	94
7.10 Examples	94
7.10.1 Read Coil Status (01 hex)	94
7.10.2 Force/Write Single Coil (05 hex)	95
7.10.3 Force/Write Multiple Coils (0F hex)	95
7.10.4 Read Holding Registers (03 hex)	96
7.10.5 Preset Single Register (06 hex)	96
7.10.6 Preset Multiple Registers (10 hex)	97
7.10.7 Read/Write Multiple Registers (17 hex)	97
7.11 Danfoss FC Control Pro€le	98
7.11.1 Control Word According to FC Pro€le (8-10 Protocol = FC Pro€le)	98
7.11.2 Status Word According to FC Pro€le (STW)	99
7.11.3 Bus Speed Reference Value	101

4

Danfoss A/S © 04/2018 All rights reserved.

MG18C802

Contents	Design Guide

8 General Speci€cations	102
8.1 Mechanical Dimensions	102
8.1.1 Side-by-side Installation	102
8.1.2 Frequency Converter Dimensions	103
8.1.3 Shipping Dimensions	105
8.1.4 Field Mounting	106
8.2 Mains Supply Speci€cations	107
8.2.1 3x200–240 V AC	107
8.2.2 3x380–480 V AC	108
8.2.3 3x525–600 V AC	112
8.3 Fuses and Circuit Breakers	113
8.4 General Technical Data	115
8.4.1 Mains Supply (L1, L2, L3)	115
8.4.2 Motor Output (U, V, W)	115
8.4.3 Cable Length and Cross-section	116
8.4.4 Digital Inputs	116
8.4.5 Analog Inputs	116
8.4.6 Analog Output	116
8.4.7 Digital Output	117
8.4.8 Control Card, RS485 Serial Communication	117
8.4.9 Control Card, 24 V DC Output	117
8.4.10 Relay Output	117
8.4.11 Control Card, 10 V DC Output	118
8.4.12 Ambient Conditions	118
8.5 dU/Dt	119
Index	122

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

5

Introduction VLT® HVAC Basic Drive FC 101

1	1	1 Introduction

1.1 Purpose of the Design Guide

This design guide is intended for project and systems engineers, design consultants, and application and product specialists. Technical information is provided to understand the capabilities of the frequency converter for integration into motor control and monitoring systems. Details concerning operation, requirements, and recommendations for system integration are described. Information is proved for input power characteristics, output for motor control, and ambient operating conditions for the frequency converter.

Also included are:

•Safety features.

•Fault condition monitoring.

•Operational status reporting.

•Serial communication capabilities.

•Programmable options and features.

Also provided are design details such as:

•Site requirements.

•Cables.

•Fuses.

•Control wiring.

•Unit sizes and weights.

•Other critical information necessary to plan for system integration.

Reviewing the detailed product information in the design stage enables developing a well-conceived system with optimal functionality and efficiency.

VLT® is a registered trademark.

1.2 Document and Software Version

This manual is regularly reviewed and updated. All suggestions for improvement are welcome.

with regards to backwards compatibility for H1–H5 and I2– I4 enclosure sizes. Refer to Table 1.2 for the limitations.

	Software	Old control card	New control card
		(production week	(production week
	compatibility
		33 2017 or before)	34 2017 or after)
	Old software
	(OSS-€le version 3.xx	Yes	No
	and below)
	New software
	(OSS-€le version 4.xx	No	Yes
	or higher)
	Hardware	Old control card	New control card
		(production week	(production week
	compatibility
		33 2017 or before)	34 2017 or after)
	Old power card	Yes (only software	Yes (MUST update
	(production week 33	version 3.xx or	software to version
	2017 or before)	below)	4.xx or higher)
		Yes (MUST update
	New power card	software to version	Yes (only software
	(production week 34	3.xx or below, the	version 4.xx or
	2017 or after)	fan continuously	higher)
		runs at full speed)

Table 1.2 Software and Hardware Compatibility

1.3 Safety Symbols

The following symbols are used in this guide:

WARNING

Indicates a potentially hazardous situation that could result in death or serious injury.

CAUTION

Indicates a potentially hazardous situation that could result in minor or moderate injury. It can also be used to alert against unsafe practices.

Edition	Remarks	Software version
MG18C8xx	Update to new SW & HW version.	4.2x

Table 1.1 Document and Software Version

From software version 4.0x and later (production week 33 2017 and after), the variable speed heat sink cooling fan function is implemented in the frequency converter for power sizes 22 kW (30 hp) 400 V IP20 and below, and 18.5 kW (25 hp) 400 V IP54 and below. This function requires software and hardware updates and introduces restrictions

NOTICE

Indicates important information, including situations that can result in damage to equipment or property.

6

Danfoss A/S © 04/2018 All rights reserved.

MG18C802

Introduction		Design Guide
1.4	Abbreviations			VLT® Energy Box software allows energy			1	1
				consumption comparisons of HVAC fans and
°C		Degrees Celsius		pumps driven by Danfoss frequency converters
°F		Degrees Fahrenheit		and alternative methods of flow control. Use this
A		Ampere/AMP		tool to accurately project the costs, savings, and
				payback of using Danfoss frequency converters
AC		Alternating current
				on HVAC fans, pumps, and cooling towers.
AMA		Automatic motor adaptation
AWG		American wire gauge		Danfoss technical literature is available in electronic form
DC		Direct current		on the documentation CD that is shipped with the
EMC		Electro magnetic compatibility		product, or in print from your local Danfoss sales office.
ETR		Electronic thermal relay
FC		Frequency converter		MCT 10 Set-up Software support
fM,N		Nominal motor frequency		Download the software from www.danfoss.com/en/service-
kg		Kilogram		and-support/downloads/dds/vlt-motion-control-tool-mct-10/.
Hz		Hertz		During the installation process of the software, enter
IINV		Rated inverter output current		access code 81463800 to activate the FC 101 functionality.
ILIM		Current limit		A license key is not required for using the FC 101
IM,N		Nominal motor current		functionality.
IVLT,MAX		The maximum output current		The latest software does not always contain the latest
IVLT,N		The rated output current supplied by the
				updates for frequency converters. Contact the local sales
		frequency converter
				office for the latest frequency converter updates (in the
kHz		Kilohertz
				form of *.upd €les), or download the frequency converter
LCP		Local control panel		updates from www.danfoss.com/en/service-and-support/
m		Meter		downloads/dds/vlt-motion-control-tool-mct-10/#Overview.
mA		Milliampere		1.6 De€nitions
MCT		Motion control tool
mH		Millihenry inductance		Frequency converter
min		Minute		IVLT, MAX
ms		Millisecond		The maximum output current.
nF		Nanofarad		IVLT,N
Nm		Newton meters
				The rated output current supplied by the frequency
ns		Synchronous motor speed
				converter.
PM,N		Nominal motor power
				UVLT, MAX
PCB		Printed circuit board
				The maximum output voltage.
PELV		Protective extra low voltage
				Input
Regen		Regenerative terminals
				The connected motor can start and stop via LCP and
RPM		Revolutions per minute
				digital inputs. Functions are divided into 2 groups, as
s		Second
				described in Table 1.4. Functions in group 1 have higher
TLIM		Torque limit
				priority than functions in group 2.
UM,N		Nominal motor voltage
V		Volts
				Group 1	Reset, coast stop, reset and coast stop, quick
Table 1.3 Abbreviations					stop, DC brake, stop, and [Off].
				Group 2	Start, pulse start, reversing, start reversing, jog,
1.5	Additional Resources				and freeze output.
				Table 1.4 Control Commands
•	VLT® HVAC Basic Drive FC 101 Quick Guide provides

	basic information on mechanical dimensions,	Motor
	installation, and programming.
		fJOG

•VLT® HVAC Basic Drive FC 101 Programming Guide The motor frequency when the jog function is activated

provides information on how to program, and includes complete parameter descriptions.

•Danfoss VLT® Energy Box software. Select PC Software Download at www.danfoss.com/en/ service-and-support/downloads/dds/vlt-energy-box/.

(via digital terminals).

fM

The motor frequency.

fMAX

The maximum motor frequency.

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

7

Introduction

VLT® HVAC Basic Drive FC 101

1 1 fMIN

The minimum motor frequency.

fM,N

The rated motor frequency (nameplate data).

IM

The motor current.

IM,N

The rated motor current (nameplate data).

nM,N

The nominal motor speed (nameplate data).

PM,N

The rated motor power (nameplate data).

UM

The instantaneous motor voltage.

UM,N

The rated motor voltage (nameplate data).

Break-away torque

Torque			<![if ! IE]> <![endif]>175ZA078.10
		Pull-out

RPM

Illustration 1.1 Break-away Torque

ηVLT

The efficiency of the frequency converter is de€ned as the ratio between the power output and the power input.

Start-disable command

A stop command belonging to the group 1 control commands, see Table 1.4.

Stop command

See Table 1.4.

Analog reference

A signal transmitted to the analog inputs 53 or 54. It can be voltage or current.

•Current input: 0–20 mA and 4–20 mA

•Voltage input: 0–10 V DC

Bus reference

A signal transmitted to the serial communication port (FC port).

Preset reference

A de€ned preset reference to be set from -100% to +100% of the reference range. Selection of 8 preset references via the digital terminals.

RefMAX

Determines the relationship between the reference input at 100% full scale value (typically 10 V, 20 mA) and the resulting reference. The maximum reference value set in parameter 3-03 Maximum Reference.

RefMIN

Determines the relationship between the reference input at 0% value (typically 0 V, 0 mA, 4 mA) and the resulting reference. The minimum reference value is set in

parameter 3-02 Minimum Reference.

Analog inputs

The analog inputs are used for controlling various functions of the frequency converter.

There are 2 types of analog inputs:

•Current input: 0–20 mA and 4–20 mA

•Voltage input: 0–10 V DC

Analog outputs

The analog outputs can supply a signal of 0–20 mA, 4– 20 mA, or a digital signal.

Automatic motor adaptation, AMA

The AMA algorithm determines the electrical parameters for the connected motor at standstill and compensates for the resistance based on the length of the motor cable.

Digital inputs

The digital inputs can be used for controlling various functions of the frequency converter.

Digital outputs

The frequency converter provides 2 solid-state outputs that can supply a 24 V DC (maximum 40 mA) signal.

Relay outputs

The frequency converter provides 2 programmable relay outputs.

ETR

Electronic thermal relay is a thermal load calculation based on present load and time. Its purpose is to estimate the motor temperature and prevent overheating of the motor.

Initializing

If initializing is carried out (parameter 14-22 Operation Mode), the programmable parameters of the frequency converter return to their default settings.

Parameter 14-22 Operation Mode does not initialize communication parameters, fault log, or €re mode log.

Intermittent duty cycle

An intermittent duty rating refers to a sequence of duty cycles. Each cycle consists of an on-load and an off-load period. The operation can be either periodic duty or noneperiodic duty.

8

Danfoss A/S © 04/2018 All rights reserved.

MG18C802

Introduction	Design Guide

LCP

The local control panel (LCP) makes up a complete interface for control and programming of the frequency converter. The control panel is detachable on IP20 units and €xed on IP54 units. It can be installed up to 3 m (9.8 ft) from the frequency converter, that is, in a front panel with the installation kit option.

Lsb

Least signi€cant bit.

MCM

Short for mille circular mil, an American measuring unit for cable cross-section. 1 MCM = 0.5067 mm2.

Msb

Most signi€cant bit.

On-line/Oƒ-line parameters

Changes to on-line parameters are activated immediately after the data value is changed. Press [OK] to activate offline parameters.

PI controller

The PI controller maintains the desired speed, pressure, temperature, and so on, by adjusting the output frequency to match the varying load.

RCD

Residual current device.

Set-up

Parameter settings in 2 set-ups can be saved. Change between the 2 parameter set-ups and edit 1 set-up, while another set-up is active.

Slip compensation

The frequency converter compensates for the motor slip by giving the frequency a supplement that follows the measured motor load keeping the motor speed almost constant.

Smart logic control (SLC)

The SLC is a sequence of user-de€ned actions executed when the associated user-de€ned events are evaluated as true by the SLC.

Thermistor

A temperature-dependent resistor placed where the temperature is to be monitored (frequency converter or motor).

Trip

1 1

A state entered in fault situations, for example, if the frequency converter is subject to an overtemperature or when the frequency converter is protecting the motor, process, or mechanism. Restart is prevented until the cause of the fault does not exist and the trip state is canceled by activating reset or, sometimes, by being programmed to reset automatically. Do not use trip for personal safety.

Trip lock

A state entered in fault situations when the frequency converter is protecting itself and requiring physical intervention, for example, if the frequency converter is subject to a short circuit on the output. A locked trip can only be canceled by cutting off mains, removing the cause of the fault, and reconnecting the frequency converter. Restart is prevented until the trip state is canceled by activating reset or, sometimes, by being programmed to reset automatically. Do not use trip lock for personal safety.

VT characteristics

Variable torque characteristics used for pumps and fans.

VVC+

If compared with standard voltage/frequency ratio control, voltage vector control (VVC+) improves the dynamics and the stability, both when the speed reference is changed and in relation to the load torque.

1.7 Power Factor

The power factor indicates to which extent the frequency converter imposes a load on the mains supply. The power factor is the ratio between I1 and IRMS, where I1 is the fundamental current, and IRMS is the total RMS current including harmonic currents. The lower the power factor, the higher the IRMS for the same kW performance.

3 ×

U

I

I

ϕ

U

×

1 × cos

The power factor for 3-phase control:

Power factor =

3 ×

×

RMS

Power factor

I

cos

I

since cos

=

1

I

ϕ1 =

IRMS

ϕ1 = 1

I

I

× RMS

In

1

2

I

2

I

2

RMS

2

high-power factor indicates that the different harmonic

A

=

1 +

5

+

7

+ . . +

currents are low.

The frequency converters built-in DC coils produce a highpower factor, which minimizes the imposed load on the mains supply.

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

9

Introduction

VLT® HVAC Basic Drive FC 101

1 1 1.8 Regulatory Compliance

Frequency converters are designed in compliance with the directives described in this section.

1.8.1 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 frequency converters are listed in Table 1.5.

NOTICE

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

CE mark, but must comply with the basic protection requirements of the EMC directive.

1.8.1.3 ErP Directive

The ErP directive is the European Ecodesign Directive for energy-related products. The directive sets ecodesign requirements for energy-related products, including frequency converters. The directive aims at increasing energy efficiency and the level of protection of the environment, while increasing the security of the energy supply. Environmental impact of energy-related products includes energy consumption throughout the entire product life cycle.

1.8.2 UL Compliance

UL-listed

NOTICE

Frequency converters with an integrated safety function must comply with the machinery directive.

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

Table 1.5 EU Directives Applicable to Frequency Converters

Declarations of conformity are available on request.

1.8.1.1 Low Voltage Directive

The low voltage directive applies to all electrical equipment in the 50–1000 V AC and the 75–1600 V DC voltage ranges.

The aim of the directive is to ensure personal safety and avoid property damage, when operating electrical equipment that is installed and maintained correctly in its intended application.

1.8.1.2 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 2014/30/EU 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

Illustration 1.2 UL

NOTICE

IP54 units are not certi€ed for UL.

The frequency converter complies with UL 508C thermal memory retention requirements. For more information, refer to the section Motor Thermal Protection in the product-speci€c design guide.

1.8.3 RCM Mark Compliance

Illustration 1.3 RCM Mark

The RCM Mark label indicates compliance with the applicable technical standards for Electromagnetic Compatibility (EMC). An RCM Mark label is required for placing electrical and electronic devices on the market in Australia and New Zealand. The RCM Mark regulatory arrangements only deal with conducted and radiated emission. For frequency converters, the emission limits speci€ed in EN/IEC 61800-3 apply. A declaration of conformity can be provided on request.

10

Danfoss A/S © 04/2018 All rights reserved.

MG18C802

Introduction													Design Guide
1.8.4 EAC															1	1

Illustration 1.4 EAC Mark

The EurAsian Conformity (EAC) mark indicates that the product conforms to all requirements and technical regulations applicable to the product per the EurAsian Customs Union, which is composed of the member states of the EurAsian Economic Union.

The EAC logo must be both on the product label and on the packaging label. All products used within the EAC area, must be bought at Danfoss inside the EAC area.

1.8.5 UkrSEPRO

089

Illustration 1.5 UkrSEPRO

UKrSEPRO certi€cate ensures quality and safety of both products and services, in addition to manufacturing stability according to Ukrainian regulatory standards. The UkrSepro certi€cate is a required document to clear customs for any products coming into and out of the territory of Ukraine.

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

11

Safety

VLT® HVAC Basic Drive FC 101

2 Safety

2 2

2.1 Quali€ed Personnel

Correct and reliable transport, storage, installation, operation, and maintenance are required for the troublefree and safe operation of the frequency converter. Only quali€ed personnel are allowed to install or operate this equipment.

Quali€ed personnel are de€ned as trained staff, who are authorized to install, commission, and maintain equipment, systems, and circuits in accordance with pertinent laws and regulations. Also, the personnel must be familiar with the instructions and safety measures described in this guide.

2.2 Safety Precautions

WARNING

HIGH VOLTAGE

Frequency converters contain high voltage when connected to AC mains input, DC supply, or load sharing. Failure to perform installation, start-up, and maintenance by quali€ed personnel can result in death or serious injury.

•Only quali€ed personnel must perform installation, start-up, and maintenance.

•Before performing any service or repair work, use an appropriate voltage measuring device to make sure that there is no remaining voltage on the frequency converter.

WARNING

UNINTENDED START

When the drive is connected to AC mains, DC supply, or load sharing, the motor can start at any time. Unintended start during programming, service, or repair work can result in death, serious injury, or property damage. The motor can start with an external switch, a €eldbus command, an input reference signal from the LCP or LOP, via remote operation using MCT 10 Set-up Software, or after a cleared fault condition.

To prevent unintended motor start:

•Press [Oƒ/Reset] on the LCP before programming parameters.

•Disconnect the drive from the mains.

•Completely wire and assemble the drive, motor, and any driven equipment before connecting the drive to AC mains, DC supply, or load sharing.

WARNING

DISCHARGE TIME

The frequency converter contains DC-link capacitors, which can remain charged even when the frequency converter is not powered. High voltage can be present even when the warning LED indicator lights are oƒ. Failure to wait the speci€ed time after power has been removed before performing service or repair work can result in death or serious injury.

•Stop the motor.

•Disconnect AC mains and remote DC-link power supplies, including battery back-ups, UPS, and DC-link connections to other frequency converters.

•Disconnect or lock PM motor.

•Wait for the capacitors to discharge fully. The minimum duration of waiting time is speci€ed in Table 2.1.

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

Voltage [V]	Power range [kW (hp)]	Minimum waiting time
		(minutes)
3x200	0.25–3.7 (0.33–5)	4
3x200	5.5–11 (7–15)	15
3x400	0.37–7.5 (0.5–10)	4
3x400	11–90 (15–125)	15
3x600	2.2–7.5 (3–10)	4
3x600	11–90 (15–125)	15

Table 2.1 Discharge Time

WARNING

LEAKAGE CURRENT HAZARD

Leakage currents exceed 3.5 mA. Failure to ground the frequency converter properly can result in death or serious injury.

•Ensure the correct grounding of the equipment by a certi€ed electrical installer.

12

Danfoss A/S © 04/2018 All rights reserved.

MG18C802

Safety Design Guide

WARNING

EQUIPMENT HAZARD	2 2
Contact with rotating shafts and electrical equipment

can result in death or serious injury.

•Ensure that only trained and quali€ed personnel perform installation, start-up, and maintenance.

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

•Follow the procedures in this manual.

CAUTION

INTERNAL FAILURE HAZARD

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

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

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

13

Product Overview

VLT® HVAC Basic Drive FC 101

		3 Product Overview
		3.1 Advantages
3	3	3.1.1 Why use a Frequency Converter for
					Controlling Fans and Pumps?
		A frequency converter takes advantage of the fact that
		centrifugal fans and pumps follow the laws of propor-
		tionality for such fans and pumps. For further information,
		see chapter 3.1.3 Example of Energy Savings.
		3.1.2 The Clear Advantage - Energy Savings
		The clear advantage of using a frequency converter for
		controlling the speed of fans or pumps lies in the
		electricity savings.
		When comparing with alternative control systems and
		technologies, a frequency converter is the optimum energy
		control system for controlling fan and pump systems.
			120																						<![if ! IE]> <![endif]>130BA780.11
														A
			100
<![if ! IE]> <![endif]>%																				SYSTEM CURVE
			80
		<![if ! IE]> <![endif]>PRESSURE											B								FAN CURVE
			60
			40
											C
			20
			0
					20		40		60		80		100			120				140		160	180
											VOLUME %

Illustration 3.1 Fan Curves (A, B, and C) for Reduced Fan

Volumes

	120																						<![if ! IE]> <![endif]>130BA781.11
													A
	100
																	SYSTEM CURVE
	80
<![if ! IE]> <![endif]>%											B								FAN CURVE
<![if ! IE]> <![endif]>PRESSURE	60
	40
									C
	20
	0
																	140		160
			20		40		60		80		100			120							180
									Volume %
	120
<![if ! IE]> <![endif]>%	100
	80
<![if ! IE]> <![endif]>POWER	60
<![if ! IE]> <![endif]>INPUT	40
	20			ENERGY
				CONSUMED
	0
			20		40		60		80		100			120			140		160		180
									Volume %

Illustration 3.2 Energy Savings with Frequency Converter Solution

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

3.1.3 Example of Energy Savings

As shown in Illustration 3.3, 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%.

14

Danfoss A/S © 04/2018 All rights reserved.

MG18C802

Product Overview

Design Guide

Illustration 3.3 describes the dependence of flow, pressure, and power consumption on RPM.

100%			<![if ! IE]> <![endif]>175HA208.10
80%
50%	Flow ~n
		Pressure~n 2
25%
12,5%		Power ~n3
			n
	50%	80%	100%

Illustration 3.3 Laws of Proportionally

		Q			n
Flow :		Q1	=		n1
		2		H	2	n	2
Pressure :				H1	=	n1
		P		2	n	2
Power	:	P1			n1	3
				2 =	2
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

Table 3.1 The Laws of Proportionality

3.1.4 Comparison of Energy Savings

The Danfoss frequency converter 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 frequency converter is able to control fan speed according to thermal load on the system, and the frequency converter has a built-in facility that enables the frequency converter to function as a building management system, BMS.

Illustration 3.3 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.

<![if ! IE]>

<![endif]>130BA782.10

Discharge	3	3
damper
	Less energy savings

Maximum energy savings

IGV

Costlier installation

Illustration 3.4 The 3 Common Energy Saving Systems

	100		Discharge Damper Solution						<![if ! IE]> <![endif]>130BA779.12
<![if ! IE]> <![endif]>%	80				IGV Solution
	60
			<![if ! IE]> <![endif]>Energyconsumed
<![if ! IE]> <![endif]>Inputpower
					<![if ! IE]> <![endif]>consumedEnergy			<![if ! IE]> <![endif]>consumed
	40							VLT Solution
	20
								<![if ! IE]> <![endif]>Energy
	0
	0		60	0	60		0	60

Volume %

Illustration 3.5 Energy Savings

Discharge dampers reduce power consumption. Inlet guide vanes offer a 40% reduction, but are expensive to install. The Danfoss frequency converter 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.

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

15

Product Overview

VLT® HVAC Basic Drive FC 101

3.1.5Example with Varying Flow over 1 Year

This example is calculated based on pump characteristics obtained from a pump datasheet.

3 3 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 frequency converter. In this example, it is less than a year when compared with valves and constant speed.

Energy savings

Pshaft = Pshaft output

[h] t								<![if ! IE]> <![endif]>175HA210.11
2000
1500

1000

500

						Q
100	200	300	400
					[m3 /h]

Illustration 3.6 Flow Distribution over 1 Year

(mwg)	Hs		<![if ! IE]> <![endif]>175HA209.11
60
50
		B

40

30

A 1650rpm

20

1350rpm

10								C				1050rpm
									750rpm
		0			100				200				300				400			(m3 /h)
(kW)			Pshaft
60
50
																A1
40																1650rpm
30
20								B1					1350rpm
10						C1				1050rpm
								750rpm
		0			100				200				300				400			(m3 /h)
Illustration 3.7 Energy
m3/			Distri-					Valve regulation						Frequency converter
h			bution													control
		%		Hours				Power		Consump-						Power	Consump-
												tion							tion
								A1 - B1				kWh				A1 - C1			kWh
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

Table 3.2 Result

3.1.6 Better Control

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

A frequency converter can vary the speed of the fan or pump, obtaining variable control of flow and pressure. Furthermore, a frequency converter 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.

16

Danfoss A/S © 04/2018 All rights reserved.

MG18C802

Product Overview

Design Guide

3.1.7Star/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 frequency converter is used.

As illustrated in Illustration 3.8, a frequency converter does not consume more than rated current.

	800														<![if ! IE]> <![endif]>175HA227.10
	700
	600										4
<![if ! IE]> <![endif]>current	500
	400
<![if ! IE]> <![endif]>-load	300										3
<![if ! IE]> <![endif]>% Full
	200
											2
	100							1
	0
	0				12,5			25			37,5			50Hz

Full load & speed

1VLT® HVAC Basic Drive FC 101

2Star/delta starter

3Soft starter

4Start directly on mains

Illustration 3.8 Start-up Current

3.1.8Using a Frequency Converter Saves Money

The example in chapter 3.1.9 Without a Frequency Converter shows that a frequency converter replaces other

equipment. It is possible to calculate the cost of installing 3 3 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 1.5 Additional Resources to calculate the cost savings that can be achieved by using a frequency converter.

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

17

Product Overview

VLT® HVAC Basic Drive FC 101

3.1.9 Without a Frequency Converter

Cooling section

Heating section

Inlet guide vane

Fan section

-

+

M

Supply

<![if ! IE]> <![endif]>175HA205.12

3

3

Fan

air

V.A.V

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

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

Illustration 3.9 Traditional Fan System

18

Danfoss A/S © 04/2018 All rights reserved.

MG18C802

Product Overview	Design Guide

3.1.10 With a Frequency Converter

Cooling section		Heating section			Fan section			<![if ! IE]> <![endif]>175HA206.11
						Supply
					Fan	air			3	3
							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

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

Illustration 3.10 Fan System Controlled by Frequency Converters

3.1.11 Application Examples

The following sections give typical examples of applications within HVAC.

3.1.12 Variable Air Volume

VAV or variable air volume systems, control both the ventilation and temperature to ful€ll 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.

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

19

Product Overview

VLT® HVAC Basic Drive FC 101

3.1.13 The VLT Solution

While dampers and IGVs work to maintain a constant pressure in the ductwork, a frequency converter solution saves much more energy and reduces the complexity of

3 3 the installation. Instead of creating an arti€cial pressure drop or causing a decrease in fan efficiency, the frequency converter 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 signi€cantly reduced. The PI controller of the VLT® HVAC Basic Drive FC 101 can be used to eliminate the need for additional controllers.

			Pressure
Cooling coil	Heating coil	Frequency	signal
	Filter	converter			VAV boxes
			Supply fan
D1			3		T
					Pressure
				Flow	transmitter
D2
		Frequency
		converter	Return fan
				Flow
			3
D3

Illustration 3.11 Variable Air Volume

<![if ! IE]>

<![endif]>130BB455.10

20

Danfoss A/S © 04/2018 All rights reserved.

MG18C802

Product Overview	Design Guide

3.1.14 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.

3.1.15 The VLT Solution

With a frequency converter, signi€cant energy savings can be obtained while maintaining decent control of the building. Temperature sensors or CO2 sensors can be used as feedback signals to frequency converters. 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 €xed 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 3 3 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 HVAC dedicated frequency converter 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 frequency converter also includes a PI controller, which allows monitoring both temperature and air quality. Even if the temperature requirement is ful€lled, the frequency converter 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 €xed differential airflow between the supply and return ducts as well.

Cooling coil	Heating coil		Temperature	<![if ! IE]> <![endif]>130BB451.10
		Frequency	signal
		converter
		Filter
			Supply fan
D1
				Temperature
				transmitter
D2			Pressure
			signal
		Frequency
		converter	Return fan
D3				Pressure
				transmitter

Illustration 3.12 Constant Air Volume

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

21

Product Overview

VLT® HVAC Basic Drive FC 101

3.1.16 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

3 3 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 €ll to increase its surface area. The tower fan blows air through the €ll 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.

Several features of the Danfoss HVAC dedicated frequency converter 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 frequency converter 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 frequency converter.

3.1.17 The VLT Solution

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

<![if ! IE]>

<![endif]>130BB453.10

Frequency converter

Water Inlet

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

Supply

Illustration 3.13 Cooling Tower Fan

22

Danfoss A/S © 04/2018 All rights reserved.

MG18C802

Product Overview	Design Guide

3.1.18 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.

Using a frequency converter 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.	3	3

3.1.19 The VLT Solution

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

	Frequency	<![if ! IE]> <![endif]>130BB452.10
	converter
	Water
	Inlet
	Flow or pressure sensor
	BASIN
	Water	<![if ! IE]> <![endif]>CHILLER
	Outlet
		Throttling
	Condenser	valve
	Water pump
		Supply

Illustration 3.14 Condenser Pumps

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

23

Product Overview VLT® HVAC Basic Drive FC 101

3.1.20 Primary Pumps 3.1.21 The VLT Solution

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

3 3 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.

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 frequency converter 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 frequency converter 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 frequency converter 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 €xed. 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 €xed speed remains appropriate. If the flow rate needs to be increased later in the system’s life, the frequency converter can simply increase the pump speed instead of requiring a new pump impeller.

24

Danfoss A/S © 04/2018 All rights reserved.

MG18C802

Product Overview

Design Guide

Flowmeter	Flowmeter
F	F

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

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

Frequency Frequency converter converter

Illustration 3.15 Primary Pumps

<![if ! IE]>

<![endif]>130BB456.10

3 3

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

25

Product Overview

VLT® HVAC Basic Drive FC 101

3.1.22 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

3 3 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.

3.1.23 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 frequency converters.

With the proper sensor location, the addition of frequency converters 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.

NOTICE

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

				P	<![if ! IE]> <![endif]>130BB454.10
			Frequency
			converter
			3
<![if ! IE]> <![endif]>CHILLER	<![if ! IE]> <![endif]>CHILLER	Frequency	3
		converter

Illustration 3.16 Secondary Pumps

26

Danfoss A/S © 04/2018 All rights reserved.

MG18C802

Product Overview	Design Guide

3.2 Control Structures

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

3.2.1 Control Structure Open Loop

Reference handling Remote reference

Auto mode

Hand mode

Local reference scaled to Hz

LCP Hand on, o and auto on keys

P 4-14 Motor speed

high limit [Hz]

Remote

Reference

Local

P 4-12 Motor speed low limit [Hz]

P 3-4* Ramp 1

P 3-5* Ramp 2

Ramp

100%	<![if ! IE]> <![endif]>130BB892.10
0%	To motor
	control

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

Illustration 3.17 Open-loop Structure

In the con€guration shown in Illustration 3.17,

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.

3.2.2 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 frequency converters.

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 retro€t of existing installations.

•Power range: 45 kW (60 hp) (200 V), 0.37–90 kW (0.5–121 hp) (400 V), 90 kW (121 hp) (600 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 €lters 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 2.80).

3.2.3Local (Hand On) and Remote (Auto On) Control

The frequency converter 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 frequency converter via LCP by pressing [Hand On] and [Off/Reset]. Alarms can be reset via the [Off/Reset] key.

Hand	O	Auto	<![if ! IE]> <![endif]>130BB893.10
On	Reset	On

Illustration 3.18 LCP Keys

3 3

MG18C802

Danfoss A/S © 04/2018 All rights reserved.

27

Product Overview

VLT® HVAC Basic Drive FC 101

Local reference forces the con€guration mode to openloop, independent on the setting of

parameter 1-00 Configuration Mode.

Local reference is restored at power-down.

3 3 3.2.4 Control Structure Closed Loop

The internal controller allows the frequency converter to become a part of the controlled system. The frequency converter 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.

Reference	+	S
	_	PI

*[-1]

Feedback

7-30 PI

Normal/Inverse

Control

Illustration 3.19 Control Structure Closed-loop

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

For example, consider a pump application where the speed of a pump is to be controlled to ensure a constant static pressure in a pipe. The static pressure value is supplied to the frequency converter as the setpoint reference. A static pressure sensor measures the actual static pressure in the pipe and supplies this data to the frequency converter as a feedback signal. If the feedback signal is greater than the setpoint reference, the frequency converter slows the pump down to reduce the pressure. In a similar way, if the pipe pressure is lower than the setpoint reference, the frequency converter automatically speeds the pump up to increase the pressure provided by the pump.

100%

0%

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

<![if ! IE]>

<![endif]>130BB894.11

Scale to		To motor
speed		control

3.2.5 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

Illustration 3.20.

Ref.					<![if ! IE]> <![endif]>130BB895.10
signal
	Ref.+			PI
	P 20-01	-
Desired
	FB conversion
ow			FB		P
				Flow	Flow
	FB				P
	signal
			P

Illustration 3.20 Feedback Signal Conversion

28

Danfoss A/S © 04/2018 All rights reserved.

MG18C802