Danfoss FC 280 Design guide

ENGINEERING TOMORROW

Design Guide

VLT® Midi Drive FC 280

vlt-drives.danfoss.com

Contents	Design Guide

Contents

1 Introduction	5
1.1 Purpose of the Design Guide	5
1.2 Additional Resources	5
1.3 De€nitions	5
1.4 Document and Software Version	8
1.5 Approvals and Certi€cations	8
1.6 Safety	9
2 Product Overview	10
2.1 Enclosure Size Overview	10
2.2 Electrical Installation	12
2.2.1 Motor Connection	14
2.2.2 AC Mains Connection	15
2.2.3 Control Terminal Types	16
2.2.4 Wiring to Control Terminals	17
2.3 Control Structures	18
2.3.1 Control Modes	18
2.3.2 Control Principle	19
2.3.3 Control Structure in VVC+	19
2.3.4 Internal Current Control in VVC+ Mode	21
2.3.5 Local (Hand On) and Remote (Auto On) Control	21
2.4 Reference Handling	22
2.4.1 Reference Limits	23
2.4.2 Scaling of Preset References and Bus References	24
2.4.3 Scaling of Analog and Pulse References and Feedback	24
2.4.4 Dead Band Around Zero	25
2.5 PID Control	28
2.5.1 Speed PID Control	28
2.5.2 Process PID Control	31
2.5.3 Process Control Relevant Parameters	32
2.5.4 Example of Process PID Control	33
2.5.5 Process Controller Optimization	35
2.5.6 Ziegler Nichols Tuning Method	36
2.6 EMC Emission and Immunity	36
2.6.1 General Aspects of EMC Emission	36
2.6.2 EMC Emission	38
2.6.3 EMC Immunity	40
2.7 Galvanic Isolation	41
2.8 Ground Leakage Current	41

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Contents

VLT® Midi Drive FC 280

2.9 Brake Functions	42
2.9.1 Mechanical Holding Brake	42
2.9.2 Dynamic Braking	43
2.9.3 Brake Resistor Selection	43
2.10 Motor Insulation	44
2.10.1 Sine-wave Filters	44
2.10.2 dU/dt Filters	45
2.11 Smart Logic Controller	45
2.12 Extreme Running Conditions	46
2.12.1 Motor Thermal Protection	46

3 Application Examples	48
3.1 Introduction	48
3.1.1 Encoder Connection	48
3.1.2 Encoder Direction	48
3.1.3 Closed-loop Drive System	48
3.2 Application Examples	49
3.2.1 AMA	49
3.2.2 Speed	49
3.2.3 Start/Stop	50
3.2.4 External Alarm Reset	51
3.2.5 Motor Thermistor	51
3.2.6 SLC	51
4 Safe Torque Off (STO)	52
5 RS485 Installation and Set-up	53
5.1 Introduction	53
5.1.1 Overview	53
5.1.2 Network Connection	53
5.1.3 Hardware Set-up	54
5.1.4 Parameter Settings for Modbus Communication	54
5.1.5 EMC Precautions	54
5.2 FC Protocol	54
5.2.1 Overview	54
5.2.2 FC with Modbus RTU	55
5.3 Network Con€guration	55
5.4 FC Protocol Message Framing Structure	55
5.4.1 Content of a Character (byte)	55
5.4.2 Telegram Structure	55
5.4.3 Telegram Length (LGE)	55

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MG07B302

Contents	Design Guide

5.4.4 Frequency Converter Address (ADR)	56
5.4.5 Data Control Byte (BCC)	56
5.4.6 The Data Field	56
5.4.7 The PKE Field	56
5.4.8 Parameter Number (PNU)	57
5.4.9 Index (IND)	57
5.4.10 Parameter Value (PWE)	57
5.4.11 Data Types Supported by the Frequency Converter	57
5.4.12 Conversion	57
5.4.13 Process Words (PCD)	58
5.5 Examples	58
5.5.1 Writing a Parameter Value	58
5.5.2 Reading a Parameter Value	58
5.6 Modbus RTU	59
5.6.1 Prerequisite Knowledge	59
5.6.2 Overview	59
5.6.3 Frequency Converter with Modbus RTU	59
5.7 Network Con€guration	59
5.8 Modbus RTU Message Framing Structure	60
5.8.1 Introduction	60
5.8.2 Modbus RTU Telegram Structure	60
5.8.3 Start/Stop Field	60
5.8.4 Address Field	60
5.8.5 Function Field	60
5.8.6 Data Field	61
5.8.7 CRC Check Field	61
5.8.8 Coil Register Addressing	61
5.8.9 How to Control the Frequency Converter	63
5.8.10 Function Codes Supported by Modbus RTU	63
5.8.11 Modbus Exception Codes	63
5.9 How to Access Parameters	63
5.9.1 Parameter Handling	63
5.9.2 Storage of Data	64
5.9.3 IND (Index)	64
5.9.4 Text Blocks	64
5.9.5 Conversion Factor	64
5.9.6 Parameter Values	64
5.10 Examples	64
5.10.1 Read Coil Status (01 hex)	64
5.10.2 Force/Write Single Coil (05 hex)	65

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Contents

VLT® Midi Drive FC 280

5.10.3 Force/Write Multiple Coils (0F hex)	65
5.10.4 Read Holding Registers (03 hex)	65
5.10.5 Preset Single Register (06 hex)	66
5.10.6 Preset Multiple Registers (10 hex)	66
5.11 Danfoss FC Control Pro€le	67
5.11.1 Control Word According to FC Pro€le (8-10 Protocol = FC Pro€le)	67
5.11.2 Status Word According to FC Pro€le (STW)	68
5.11.3 Bus Speed Reference Value	70

6 Type Code and Selection	71
6.1 Type Code	71
6.2 Ordering Numbers: Options, Accessories, and Spare Parts	71
6.3 Ordering Numbers: Brake Resistors	73
6.3.1 Ordering Numbers: Brake Resistors 10%	73
6.3.2 Ordering Numbers: Brake Resistors 40%	75
6.4 Ordering Numbers: Sine-wave Filters	76
6.5 Ordering Numbers: dU/dt Filters	77
6.6 Ordering Numbers: External EMC Filters	77
7 Specifications	80
7.1 Electrical Data	80
7.2 Mains Supply	83
7.3 Motor Output and Motor Data	83
7.4 Ambient Conditions	84
7.5 Cable Speci€cations	84
7.6 Control Input/Output and Control Data	85
7.7 Connection Tightening Torques	88
7.8 Fuses and Circuit Breakers	89
7.9 E‚ciency	90
7.10 Acoustic Noise	91
7.11 dU/dt Conditions	91
7.12 Special Conditions	92
7.12.1 Manual Derating	93
7.12.2 Automatic Derating	95
7.13 Enclosure Sizes, Power Ratings, and Dimensions	96
Index	99

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MG07B302

Introduction Design Guide

1 Introduction	1	1

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 provided for input power characteristics, output for motor control, and ambient operating conditions for the frequency converter.

1.3De€nitions

1.3.1Frequency Converter

Coast

The motor shaft is in free mode. No torque on the motor.

IVLT,MAX

Maximum output current.

IVLT,N

Rated output current supplied by the frequency converter.

UVLT,MAX

Also included are:

•Safety features.

•Fault condition monitoring.

•Operational status reporting.

•Serial communication capabilities.

•Programmable options and features.

Design details such as site requirements, cables, fuses, control wiring, the size and weight of units, and other critical information necessary to plan for system integration are also provided.

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

VLT® is a registered trademark.

Maximum output voltage.

1.3.2 Input

Control commands

Start and stop the connected motor with LCP and digital inputs.

Functions are divided into 2 groups.

Functions in group 1 have higher priority than functions in group 2.

Group 1 Precise stop, coast and reset stop, precise stop and coast stop, quick stop, DC braking, stop, and [OFF].

Group 2 Start, pulse start, reversing, start reversing, jog, and freeze output.

Table 1.1 Function Groups

1.2 Additional Resources

Resources available to understand operations and programming of the frequency converter:

•VLT® Midi Drive FC 280 Operating Guide, provides information about the installation, commissioning, application, and maintenance of the frequency converter.

•VLT® Midi Drive FC 280 Programming Guide, provides information on how to program and includes complete parameter descriptions.

Supplementary publications and manuals are available from Danfoss. See drives.danfoss.com/knowledge-center/ technical-documentation/ for listings.

1.3.3 Motor

Motor running

Torque generated on the output shaft and speed from 0 RPM to maximum speed on the motor.

fJOG

Motor frequency when the jog function is activated (via digital terminals or bus).

fM

Motor frequency.

fMAX

Maximum motor frequency.

fMIN

Minimum motor frequency.

fM,N

Rated motor frequency (nameplate data).

IM

Motor current (actual).

IM,N

Nominal motor current (nameplate data).

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Introduction

VLT® Midi Drive FC 280

1 1 nM,N

Nominal motor speed (nameplate data).

ns

Synchronous motor speed.

ns	= 2 ×	Parameter 1 23		× 60	s
		Parameter 1
			39

nslip

Motor slip.

PM,N

Rated motor power (nameplate data in kW or hp).

TM,N

Rated torque (motor).

UM

Instantaneous motor voltage.

UM,N

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 e‚ciency of the frequency converter is de€ned as the ratio between the power output and the power input.

Start-disable command

A start-disable command belonging to the control commands in group 1. See Table 1.1 for more details.

Stop command

A stop command belonging to the control commands in group 1. See Table 1.1 for more details.

1.3.4 References

Analog reference

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

Binary reference

A signal transmitted via the serial communication 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. Selection of 4 preset references via the bus.

Pulse reference

A pulse frequency signal transmitted to the digital inputs (terminal 29 or 33).

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 is 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.

1.3.5 Miscellaneous

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, or 4– 20 mA.

Automatic motor adaptation, AMA

The AMA algorithm determines the electrical parameters for the connected motor at standstill.

Brake resistor

The brake resistor is a module capable of absorbing the brake power generated in regenerative braking. This regenerative brake power increases the DC-link voltage, and a brake chopper ensures that the power is transmitted to the brake resistor.

CT characteristics

Constant torque characteristics used for all applications such as conveyor belts, displacement pumps, and cranes.

Digital inputs

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

Digital outputs

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

DSP

Digital signal processor.

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MG07B302

Introduction	Design Guide

ETR

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

FC standard bus

Includes RS485 bus with FC protocol or MC protocol. See parameter 8-30 Protocol.

Initializing

If initializing is carried out (parameter 14-22 Operation Mode), the frequency converter returns to the default setting.

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 nonperiodic duty.

LCP

The local control panel makes up a complete interface for control and programming of the frequency converter. The LCP is detachable. With the installation kit option, the LCP can be installed up to 3 m (9.8 ft) from the frequency converter in a front panel.

NLCP

The numerical local control panel interface for control and programming of the frequency converter. The display is numerical and the panel is used to show process values. The NLCP has storing and copy functions.

GLCP

The graphic local control panel interface for control and programming of the frequency converter. The display is graphic and the panel is used to show process values. The GLCP has storing and copy functions.

lsb

Least signi€cant bit.

msb

Most signi€cant bit.

MCM

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

On-line/off-line parameters

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

Process PID

The PID control maintains speed, pressure, and temperature by adjusting the output frequency to match the varying load.

PCD

Process control data.

PFC

Power factor correction.

Power cycle

1 1

Switch off the mains until the display (LCP) is dark, then turn power on again.

Power factor

The power factor is the relation between I1 and IRMS.

	= 3		x U x I		1	cos	ϕ1
Power factor			3
				x U x IRMS

For FC 280 frequency converters, cosϕ1 = 1, therefore:

Power factor	=	I	1	x cos		ϕ1	=	I	1
					RMS
				I				IRMS

The power factor indicates to which extent the frequency converter imposes a load on the mains supply.

The lower the power factor, the higher the IRMS for the same kW performance.

IRMS = I21 + I25 + I27 + .. + I2n

In addition, a high power factor indicates that the different harmonic currents are low.

The built-in DC coils (T2/T4) and PFC (S2) produce a high power factor, minimizing the imposed load on the mains supply.

Pulse input/incremental encoder

An external, digital pulse transmitter used for feeding back information on motor speed. The encoder is used in applications where great accuracy in speed control is required.

RCD

Residual current device.

Set-up

Save parameter settings in 4 set-ups. Change among the 4 parameter set-ups and edit 1 set-up while this set-up is inactive.

SFAVM

Acronym describing the switching pattern stator fluxoriented asynchronous vector modulation.

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 smart logic controller evaluates the associated user-de€ned events as true (Parameter group 13-** Smart Logic Control).

STW

Status word.

THD

Total harmonic distortion states the total contribution of harmonic distortion.

Thermistor

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

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Introduction

VLT® Midi Drive FC 280

1 1 Trip

Trip is a state entered in fault situations. Examples of fault situations:

•The frequency converter is subject to an over voltage.

•The frequency converter protects the motor, process, or mechanism.

Restart is prevented until the cause of the fault has disappeared, and the trip state is canceled by activating reset or, in some cases, by being programmed to reset automatically. Do not use trip for personal safety.

Trip lock

Trip lock is a state entered in fault situations when the frequency converter is protecting itself and requiring physical intervention. For example, a short circuit on the output triggers a trip lock. 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 stability, both when the speed reference is changed and in relation to the load torque.

60° AVM

Refer to the switching pattern 60° asynchronous vector modulation.

1.4 Document and Software Version

This manual is regularly reviewed and updated. All suggestions for improvement are welcome. Table 1.2 shows the document version and the corresponding software version.

	Edition	Remarks	Software
			version
	MG07B3	More information for POWERLINK and	1.3
		software update.

Table 1.2 Document and Software Version

1.5 Approvals and Certi€cations

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

1.5.1 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:

•The Low Voltage Directive.

•The EMC Directive.

•The Machinery Directive (for units with an integrated safety function).

The CE mark is intended to eliminate technical barriers to free trade between the EC and EFTA states inside the ECU. The CE mark does not regulate the quality of the product. Technical speci€cations cannot be deduced from the CE mark.

1.5.2 Low Voltage Directive

Frequency converters are classi€ed as electronic components and must be CE labeled in accordance with the Low Voltage Directive. The directive applies to all electrical equipment in the 50–1000 V AC and the 75– 1500 V DC voltage ranges.

The directive mandates that the equipment design must ensure the safety and health of people and livestock, and the preservation of material by ensuring the equipment is properly installed, maintained, and used as intended.

Danfoss CE labels comply with the Low Voltage Directive, and Danfoss provides a declaration of conformity at request.

1.5.3 EMC Directive

Electromagnetic compatibility (EMC) means that electromagnetic interference between pieces of equipment does not hinder their performance. 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.

A frequency converter can be used as standalone device or as part of a more complex installation. Devices in either of these cases must bear the CE mark. Systems must not be CE marked but must comply with the basic protection requirements of the EMC directive.

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MG07B302

Introduction Design Guide

1.5.4 UL Compliance	1	1
UL-listed

Illustration 1.2 UL

Applied standards and compliance for STO

Using STO on terminals 37 and 38 requires ful€llment of all provisions for safety including relevant laws, regulations, and guidelines. The integrated STO function complies with the following standards:

•IEC/EN 61508:2010, SIL2

•IEC/EN 61800-5-2:2007, SIL2

•IEC/EN 62061:2015, SILCL of SIL2

•EN ISO 13849-1:2015, Category 3 PL d

Frequency converters can be subject to regional and/or national export control regulations.

An ECCN number is used to classify all frequency converters that are subject to export control regulations.

The ECCN number is provided in the documents accompanying the frequency converter.

In case of re-export, it is the responsibility of the exporter to ensure compliance with the relevant export control regulations.

1.6 Safety

Frequency converters contain high-voltage components and have the potential for fatal injury if handled improperly. Only quali€ed personnel are allowed to install and operate the equipment. Do not attempt repair work without €rst removing power from the frequency converter and waiting the designated duration of time for stored electrical energy to dissipate.

Refer to the operating instructions shipped with the unit, and available online for:

•Discharge time.

•Detailed safety instructions and warnings.

Strict adherence to safety precautions and notices is mandatory for safe operation of the frequency converter.

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9

Product Overview

VLT® Midi Drive FC 280

2 Product Overview

2 2

2.1 Enclosure Size Overview

Enclosure size depends on power range. For details about dimensions, refer to chapter 7.13 Enclosure Sizes, Power Ratings, and Dimensions.

	Enclosure	K1	K2	K3	K4	K5
	size
		<![if ! IE]> <![endif]>130BA870.10	<![if ! IE]> <![endif]>130BA809.10	<![if ! IE]> <![endif]>130BA810.10	<![if ! IE]> <![endif]>130BA810.10	<![if ! IE]> <![endif]>130BA810.10
	Enclosure	IP20	IP20	IP20	IP20	IP20
	protection1)
	Power
	range
	[kW (hp)]	0.37–2.2 (0.5–3.0)	3.0–5.5 (5.0–7.5)	7.5 (10)	11–15 (15–20)	18.5–22 (25–30)
	3-phase
	380–480 V
	Power
	range
	[kW (hp)]	0.37–1.5 (0.5–2.0)	2.2 (3.0)	3.7 (5.0)	–	–
	3-phase
	200–240 V
	Power
	range
	[kW (hp)]	0.37–1.5 (0.5–2.0)	2.2 (3.0)	–	–	–
	single-
	phase
	200–240 V
	Table 2.1 Enclosure Sizes
	1) IP21 is available for some variants of VLT® Midi Drive FC 280. With IP21 kit options mounted, all power sizes can be IP21.

Enclosure size is used throughout this guide whenever procedures or components differ between frequency converters based on physical size.

Find the enclosure size using the following steps:

1.Obtain the following information from the type code on the nameplate. Refer to Illustration 2.1. 1a Product group and frequency converter series (characters 1–6), for example FC 280. 1b Power rating (characters 7–10), for example PK37.

1c Voltage rating (phases and mains) (characters 11–12), for example T4.

2.Within Table 2.2, €nd the power rating and voltage rating, and look up the enclosure size of FC 280.

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Product Overview

Design Guide

VLT

2

www.danfoss.com

<![if ! IE]> <![endif]>130BF709.10

1

3

Midi Drive

T/C:

FC-

280PK37T4E20H1BXCXXXSXXXXAX

P/N: 134U2184

S/N: 000000G000

0.37kW 0.5HP

IN: 3x380-480V 50/60Hz, 1.2/1.0A

OUT: 3x0-Vin 0-500Hz, 1.2/1.1A

www.tuv.com

IP20

ID 0600000000

MADE IN

Danfoss A/S, 6430 Nordborg, Denmark

DENMARK

Enclosure: See manual

US LISTED 5AF3 E358502 IND.CONT.EQ.

CAUTION / ATTENTION:

See manual for special condition/mains fuse

Voir manual de conditions speciales/fusibles

WARNING / AVERTISSEMENT:

Stored charge, wait 4 min.

Charge résiduelle, attendez 4 min.

1		Product group and frequency converter series
2		Power rating
3		Voltage rating (phases and mains)
Illustration 2.1 Using the Nameplate to Find the Enclosure Size
	Power rating in		Power		Voltage rating in	Phases and mains voltage		Enclosure size	Frequency
		nameplate	[kW (hp)]		nameplate				converter
		PK37	0.37 (0.5)
		PK55	0.55	(0.75)
		PK75	0.75 (1.0)					K1	K1T4
		P1K1	1.1	(1.5)
		P1K5	1.5	(2.0)
		P2K2	2.2	(3.0)
		P3K0	3 (4.0)		T4		3-phase 380–480 V
								K2	K2T4
		P4K0	4 (5.0)
		P5K5	5.5	(7.5)
		P7K5	7.5 (10)					K3	K3T4
		P11K	11	(15)				K4	K4T4
		P15K	15	(20)
		P18K	18.5 (25)					K5	K5T4
		P22K	22	(30)
		PK37	0.37 (0.5)
		PK55	0.55	(0.75)
		PK75	0.75 (1.0)					K1	K1T2
					T2		3-phase 200–240 V
		P1K1	1.1	(1.5)
		P1K5	1.5	(2.0)
		P2K2	2.2	(3.0)				K2	K2T2
		P3K7	3.7	(5.0)				K3	K3T2
		PK37	0.37 (0.5)
		PK55	0.55	(0.75)
		PK75	0.75 (1.0)		S2		Single phase 200–240 V	K1	K1S2
		P1K1	1.1	(1.5)
		P1K5	1.5	(2.0)
		P2K2	2.2	(3.0)				K2	K2S2

Table 2.2 Enclosure Size of FC 280

2 2

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11

Product Overview

VLT® Midi Drive FC 280

2.2 Electrical Installation

2	2	This section describes how to wire the frequency converter.

	RFI
Power	91	(L1/N)
	92 (L2/L)
input	93 (L3)
	95	PE
			Switch mode
			power supply
			10 V DC		24 V DC
			15 mA		100 mA
+10 V DC	50	(+10 V OUT)	+ -	+	-

0−10 V DC	53	(A IN) 2)
0−10 V DC	54	(A IN)
0/4−20 mA

55 (COM digital/analog I/O)

12	(+24 V OUT)
13	(+24 V OUT)						P 5-00
									24 V (NPN)
18	(D IN)								0 V (PNP)
									24 V (NPN)
19	(D IN)								0 V (PNP)

27	(D IN/OUT)		24 V (NPN)
		24 V	0 V (PNP)
		0 V
29	(D IN)		24 V (NPN)
			0 V (PNP)
32	(D IN)		24 V (NPN)
			0 V (PNP)

							24 V (NPN)
33 (D IN)							0 V (PNP)

37(STO1)4)

38(STO2)4)

				(U) 96
				(V) 97
				(W) 98
				(PE) 99
1)			(-DC) 88 5)

(+DC/R+) 89 5)

(R-) 81

Relay 1

03 02

01

			(A OUT) 42
	3)
	<![if ! IE]> <![endif]>2 1	<![if ! IE]> <![endif]>ON	ON = Terminated
			OFF = Open
		5 V
			S801	0 V
	RS485		(N RS485)	69
	interface
			(P RS485)	68
	0 V		(COM RS485) 61

Motor

Brake resistor

250 V AC, 3 A

Analog output 0/4−20 mA

RS485

(PNP) = Source

(NPN) = Sink

Illustration 2.2 Basic Wiring Schematic Drawing

A = Analog, D = Digital

1)Built-in brake chopper is only available on 3-phase units.

2)Terminal 53 can also be used as digital input.

3)Switch S801 (bus terminal) can be used to enable termination on the RS485 port (terminals 68 and 69).

4)Refer to chapter 4 Safe Torque O€ (STO) for the correct STO wiring.

5)The S2 (single-phase 200–240 V) frequency converter does not support load sharing application.

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1
2
3
4
L1
L2
L3
PE
5

			6	<![if ! IE]> <![endif]>130BF228.10
			7		2	2
			8
			9
			10
			11
			12
		90
			13
			14
			15
4		u
			16
		v
	4	w
		PE
			17
			18

1	PLC	10	Mains cable (unshielded)
2	Minimum 16 mm2 (6 AWG) equalizing cable	11	Output contactor, and so on.
3	Control cables	12	Cable insulation stripped
4	Minimum 200 mm (656 ft) between control cables, motor	13	Common ground busbar. Follow local and national
	cables, and mains cables.		requirements for cabinet grounding.
5	Mains supply	14	Brake resistor
6	Bare (unpainted) surface	15	Metal box
7	Star washers	16	Connection to motor
8	Brake cable (shielded)	17	Motor
9	Motor cable (shielded)	18	EMC cable gland

Illustration 2.3 Typical Electrical Connection

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Product Overview

VLT® Midi Drive FC 280

2.2.1 Motor Connection

2 2 WARNING

INDUCED VOLTAGE

Induced voltage from output motor cables that run together can charge equipment capacitors, even when the equipment is turned off and locked out. Failure to run output motor cables separately or use shielded cables could result in death or serious injury.

•Run output motor cables separately.

•Use shielded cables.

•Comply with local and national electrical codes for cable sizes. For maximum cable sizes, see chapter 7.1 Electrical Data.

•Follow motor manufacturer wiring requirements.

•Motor wiring knockouts or access panels are provided at the base of IP21 (NEMA type 1) units.

•Do not wire a starting or pole-changing device (for example Dahlander motor or slip ring induction motor) between the frequency converter and the motor.

			W
		V	98
	U
		97
	96

Illustration 2.4 Motor Connection

<![if ! IE]>

<![endif]>130BD531.10

Procedure

1.Strip a section of the outer cable insulation. Recommended length is 10–15 mm (0.4–0.6 in).

2.Position the stripped cable under the cable clamp to establish mechanical €xation and electrical contact between the cable shield and ground.

The mains, motor, and grounding connection for singlephase and 3-phase frequency converters are shown in

Illustration 2.5, Illustration 2.6, and Illustration 2.7, respectively. Actual con€gurations vary with unit types and optional equipment.

3.Connect the ground cable to the nearest grounding terminal in accordance with the grounding instructions provided in chapter Grounding in the VLT® Midi Drive FC 280 Operating Guide. See Illustration 2.4.

4.Connect the 3-phase motor wiring to terminals 96 (U), 97 (V), and 98 (W), as shown in

Illustration 2.4.

5.Tighten the terminals in accordance with the information provided in chapter 7.7 Connection Tightening Torques.

NOTICE

In motors without phase insulation, paper, or other insulation reinforcement suitable for operation with voltage supply, use a sine-wave filter on the output of the frequency converter.

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Design Guide

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2 2

Illustration 2.5 Mains, Motor, and Grounding Connection for Single-phase Units (K1, K2)

<![if ! IE]>

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Illustration 2.6 Mains, Motor, and Grounding Connection for 3- phase Units (K1, K2, K3)

Illustration 2.7 Mains, Motor, and Grounding Connection for 3- phase Units (K4, K5)

2.2.2 AC Mains Connection

•Size the wiring based on the input current of the frequency converter. For maximum wire sizes, see chapter 7.1 Electrical Data.

•Comply with local and national electrical codes for cable sizes.

Procedure

1.Connect the AC input power cables to terminals N and L for single-phase units (see

Illustration 2.5), or to terminals L1, L2, and L3 for 3-phase units (see Illustration 2.6 and

Illustration 2.7).

2.Depending on the con€guration of the equipment, connect the input power to the mains input terminals or the input disconnect.

3.Ground the cable in accordance with the grounding instructions in chapter Grounding in the VLT® Midi Drive FC 280 Operating Guide.

4.When supplied from an isolated mains source (IT mains or floating delta) or TT/TN-S mains with a grounded leg (grounded delta), ensure that the RFI €lter screw is removed. Removing the RFI screw prevents damage to the DC link and reduces ground capacity currents in accordance with IEC 61800-3 (see Illustration 7.13, the RFI screw locates on the side of the frequency converter).

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Product Overview

VLT® Midi Drive FC 280

2.2.3 Control Terminal Types

2 2 Illustration 2.8 shows the removable frequency converter connectors. Terminal functions and default settings are summarized in Table 2.3 and Table 2.4.

														<![if ! IE]> <![endif]>130BE212.10
	1					2
				3
	Illustration 2.8 Control Terminal Locations
	1										2			<![if ! IE]> <![endif]>130BE214.10
	37	38	12	13	18	19	27	29	32	33	61	68	69
								3
								42	53	54	50	55

Illustration 2.9 Terminal Numbers

See chapter 7.6 Control Input/Output and Control Data for terminal ratings details.

	Terminal	Parameter	Default	Description
			setting
		Digital I/O, pulse I/O, encoder
				24 V DC supply
				voltage. Maximum
	12, 13	–	+24 V DC	output current is
				100 mA for all
				24 V loads.
		Parameter 5-10
	18	Terminal 18	[8] Start
		Digital Input		Digital inputs.
		Parameter 5-11
	19	Terminal 19	[10] Reversing
		Digital Input
		Parameter 5-01
		Terminal 27		Selectable for
		Mode		either digital
		Parameter 5-12		input, digital
	27	Terminal 27		output, or pulse
		Digital Input	DI [2] Coast	output. The
		Parameter 5-30	inverse	default setting is
		Terminal 27	DO [0] No	digital input.
		Digital Output	operation

	Terminal	Parameter	Default	Description
			setting
		Parameter 5-13	[14] Jog	Digital input.
	29	Terminal 29
		Digital Input
		Parameter 5-14	[0] No
	32	Terminal 32		Digital input, 24 V
			operation
		Digital Input		encoder. Terminal
				33 can be used for
		Parameter 5-15	[0] No
				pulse input.
	33	Terminal 33
			operation
		Digital Input
	37, 38	–	STO	Functional safety
				inputs.
		Analog inputs/outputs
				Programmable
				analog output. The
				analog signal is 0–
		Parameter 6-91	[0] No	20 mA or 4–
	42	Terminal 42		20 mA at a
			operation
		Analog Output		maximum of
				500 Ω. Can also
				be con€gured as
				digital outputs.
				10 V DC analog
				supply voltage.
	50	–	+10 V DC	15 mA maximum
				commonly used
				for potentiometer
				or thermistor.
				Analog input. Only
		Parameter		voltage mode is
	53	group 6-1*	–	supported. It can
		Analog input 53		also be used as
				digital input.
		Parameter		Analog input.
				Selectable
	54	group 6-2*	–
				between voltage
		Analog input 54
				or current mode.
				Common for
	55	–	–	digital and analog
				inputs.

Table 2.3 Terminal Descriptions - Digital Inputs/Outputs,

Analog Inputs/Outputs

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Terminal	Parameter		Default	Description
			setting
	Serial communication
				Integrated RC €lter
				for cable shield.
				ONLY for
61	–		–	connecting the
				shield when
				experiencing EMC
				problems.
	Parameter			RS485 interface. A
68 (+)	group 8-3* FC		–
				control card switch
	port settings
				is provided for
	Parameter
				termination
69 (-)	group 8-3* FC		–
				resistance.
	port settings
		Relays
				Form C relay
				output. These
				relays are in
				various locations
				depending on the
01, 02, 03	Parameter 5-40		[1] Control	frequency
	Function Relay		Ready	converter con€gu-
				ration and size.
				Usable for AC or
				DC voltage and
				resistive or
				inductive loads.

Table 2.4 Terminal Descriptions - Serial Communication

2.2.4 Wiring to Control Terminals

Control terminal connectors can be unplugged from the	2	2
frequency converter for ease of installation, as shown in

Illustration 2.8.

For details about STO wiring, refer to chapter 4 Safe Torque O€ (STO).

NOTICE

Keep control cables as short as possible and separate them from high-power cables to minimize interference.

1.Loosen the screws for the terminals.

2.Insert sleeved control cables into the slots.

3.Fasten the screws for the terminals.

4.Ensure that the contact is €rmly established and not loose. Loose control wiring can be the source of equipment faults or less than optimal operation.

See chapter 7.5 Cable Speci‚cations for control terminal cable sizes and chapter 3 Application Examples for typical control cable connections.

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Product Overview

VLT® Midi Drive FC 280

2.3 Control Structures

2 2 A frequency converter recti€es AC voltage from mains into DC voltage. Then the DC voltage is converted into an AC current with a variable amplitude and frequency.

The motor is supplied with variable voltage/current and frequency, enabling in€nitely variable speed control of 3- phased standard AC motors and permanent magnet synchronous motors.

2.3.1 Control Modes

The frequency converter controls either the speed or the torque on the motor shaft. The frequency converter also controls the process for some applications which use process data as reference or feedback, for example, temperature and pressure. Setting parameter 1-00 Con‚guration Mode determines the type of control.

Speed control

There are 2 types of speed control:

•Speed open-loop control, which does not require any feedback from the motor (sensorless).

•Speed closed-loop PID control, which requires a speed feedback to an input. A properly optimized speed closed-loop control has higher accuracy than a speed open-loop control.

Select which input to use as speed PID feedback in parameter 7-00 Speed PID Feedback Source.

Torque control

The torque control function is used in applications where the torque on motor output shaft controls the application as tension control. Select [2] Torque closed loop or [4] Torque open loop in parameter 1-00 Con‚guration Mode. Torque setting is done by setting an analog, digital, or buscontrolled reference. When running torque control, it is recommended to run a full AMA procedure, because correct motor data is important in achieving optimal performance.

•Closed loop in VVC+ mode. This function is used in applications with low to medium dynamic variation of shaft and offers excellent performance in all 4 quadrants and at all motor speeds. The speed feedback signal is mandatory. Ensure that the encoder resolution is at least 1024 PPR, and the shield cable of the encoder is properly grounded, because the accuracy of the speed feedback signal is important. Tune parameter 7-06 Speed PID Lowpass Filter Time to get the best speed feedback signal.

•Open loop in VVC+ mode. The function is used in mechanically robust applications, but the accuracy is limited. Open-loop torque function

works for 2 directions. The torque is calculated from the internal current measurement in the frequency converter.

Speed/torque reference

The reference to these controls can be either a single reference or the sum of various references including relatively scaled references. Reference handling is explained in detail in chapter 2.4 Reference Handling.

Process control

There are 2 types of process control:

•Process closed-loop control, which runs speed open-loop to control the motor internally, is a basic process PID controller.

•Extended PID speed open-loop control, which also runs speed open-loop to control the motor internally, extends the function of the basic process PID controller by adding more functions. For example, feed forward control, clamping, reference/feedback €lter, and gain scaling.

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2.3.2 Control Principle

VLT® Midi Drive FC 280 is a general-purpose frequency converter for variable speed applications. The control principle is	2	2
based on VVC+.

FC 280 frequency converters can handle asynchronous motors and permanent magnet synchronous motors up to 22 kW (30 hp).

The current-sensing principle in FC 280 frequency converters is based on the current measurement by a resistor in the DC link. The ground fault protection and short circuit behavior are handled by the same resistor.

Brake resistor

R+	R-
Load sharing + 82	81
89(+)
L1 91
L2 92
Inrush
L3 93

RFI switch

Load sharing - 88(-)

Illustration 2.10 Control Diagram

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<![endif]>130BD974.10

	U 96
	V 97	M
	W 98

2.3.3 Control Structure in VVC+

P 1-00

P 4-14 Con g. mode Motor speed

high limit (Hz) High

Ref.

+								Low
						P 4-12
S			Process			Motor speed
_						low limit (Hz)

P 7-20 Process feedback 1 source

P 7-22 Process feedback 2 source

		P 4-19		<![if ! IE]> <![endif]>130BD371.10
P 1-00		Max. output freq.
Con g. mode		+f max.
P 3-**		Motor
		controller
Ramp		-f max.
				P 4-19
				Max. output freq.
		P 7-0*		+f max.
+	S	Speed	Motor
_		PID	controller
				-f max.
		P 7-00 Speed PID

feedback source

Illustration 2.11 Control Structure in VVC+ Open-loop Configurations and Closed-loop Configurations

In the con€guration shown in Illustration 2.11, parameter 1-01 Motor Control Principle is set to [1] VVC+ and

parameter 1-00 Con‚guration Mode is set to [0] Speed open loop. The resulting reference from the reference handling system

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				Product Overview	VLT® Midi Drive FC 280
				is received and fed through the ramp limitation and speed limitation before being sent to the motor control. The output of
				the motor control is then limited by the maximum frequency limit.
2		2	If parameter 1-00 Con‚guration Mode is set to [1] Speed closed loop, the resulting reference is passed from the ramp
				limitation and speed limitation into a speed PID control. The speed PID control parameters are in parameter group 7-0*
				Speed PID Ctrl. The resulting reference from the speed PID control is sent to the motor control limited by the frequency limit.

Select [3] Process in parameter 1-00 Con‚guration Mode to use the process PID control for closed-loop control of speed or pressure in the controlled application. The process PID parameters are in parameter groups 7-2* Process Ctrl. Feedb and 7-3* Process PID Ctrl.

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2.3.4Internal Current Control in VVC+ Mode

The frequency converter features an integral current limit		2	2
control. This feature is activated when the motor current,
and thus the torque, is higher than the torque limits set in
parameter 4-16	Torque Limit Motor Mode,
parameter 4-17	Torque Limit Generator Mode, and
parameter 4-18	Current Limit.

When the frequency converter is at the current limit during motor operation or regenerative operation, the frequency converter tries to get below the preset torque limits as quickly as possible without losing control of the motor.

2.3.5Local (Hand On) and Remote (Auto On) Control

Operate the frequency converter manually via the local control panel (graphic LCP or numerical LCP) or remotely via analog/digital inputs or €eldbus.

Start and stop the frequency converter by pressing the [Hand On] and [Reset] keys on the LCP. Set-up is required via the following parameters:

•

•

•

Parameter 0-40 [Hand on] Key on LCP. Parameter 0-44 [O€/Reset] Key on LCP. Parameter 0-42 [Auto on] Key on LCP.

Reset alarms via the [Reset] key or via a digital input, when the terminal is programmed to Reset.

	Hand	O	Auto	Reset
	on		on

Illustration 2.12 GLCP Control Keys

Hand	O	Auto
On	Reset	On

<![if ! IE]>

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<![if ! IE]>

<![endif]>130BB893.10

Illustration 2.13 NLCP Control Keys

Local reference forces the con€guration mode to open loop, independent of the setting in parameter 1-00 Con‚guration Mode.

Local reference is restored when the frequency converter powers down.

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Product Overview VLT® Midi Drive FC 280

2.4 Reference Handling

2 2 Local reference

The local reference is active when the frequency converter is operated with [Hand On] active. Adjust the reference by [▲]/[▼] and [◄/[►].

Remote reference

The reference handling system for calculating the remote reference is shown in Illustration 2.14.

<![if ! IE]> <![endif]>3-18	<![if ! IE]> <![endif]>scaling ref.
<![if ! IE]> <![endif]>P	<![if ! IE]> <![endif]>Relative

<![if ! IE]>

<![endif]>Preset ref.

<![if ! IE]>

<![endif]>P 3-10

<![if ! IE]> <![endif]>P 3-15

<![if ! IE]> <![endif]>Ref.resource 1

<![if ! IE]> <![endif]>P 3-16	<![if ! IE]> <![endif]>resource 2
	<![if ! IE]> <![endif]>Ref.

<![if ! IE]> <![endif]>P 3-17	<![if ! IE]> <![endif]>resource 3
	<![if ! IE]> <![endif]>Ref.

No function

Analog ref.

Pulse ref.

Local bus ref.

DigiPot

P 3-14

Preset relative ref.

(0)

(1)

(2)

(3)

(4)

(5)

(6)

(7)

No function

Analog ref.

Pulse ref.

Local bus ref.

DigiPot

No function

Analog ref.

Pulse ref.

Local bus ref.

DigiPot

No function

Analog ref.

Pulse ref.

Local bus ref.

DigiPot

<![if ! IE]>

<![endif]>130BD374.10

P 3-04

(0)

(1)

D1

P 5-1x(15)

Preset '1'

External '0'

200%

-200%

P 3-00	P 1-00
Ref./feedback range	Con guration mode
P 5-1x(19)/P 5-1x(20)
	Speed
Freeze ref./Freeze output	open/closed loop

	P 5-1x(28)/P 5-1x(29)		-max ref./
			+max ref.
	Input command:		100%
	Catch up/ slow down
			-100%
Y	Relative	Catch up/
X	X+X*Y	slow
	/100	down
			max ref.
		P 3-12	%
	Catchup Slowdown
		value	%
			min ref.
		±100%
		Freeze ref.
		&
		increase/
		decrease
		ref.
		P 5-1x(21)/P 5-1x(22)
		Speed up/ speed down

P 16-02

Ref. in %

		Scale to
		Hz
		Torque		P 16-01
				Remote
		Scale to		ref.
		Nm
		Process
		Scale to
		process
		unit

Illustration 2.14 Remote Reference

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Design Guide

The remote reference is calculated once in every scan interval and initially consists of 2 types of reference inputs:

1.X (the external reference): A sum (see parameter 3-04 Reference Function) of up to 4 externally selected references, comprising any combination (determined by the setting of parameter 3-15 Reference 1 Source,

parameter 3-16 Reference 2 Source, and parameter 3-17 Reference 3 Source) of a €xed

preset reference (parameter 3-10 Preset Reference), variable analog references, variable digital pulse references, and various €eldbus references in any unit the frequency converter is monitoring ([Hz], [RPM], [Nm], and so on).

2.Y (the relative reference): A sum of 1 €xed preset reference (parameter 3-14 Preset Relative Reference) and 1 variable analog reference

(parameter 3-18 Relative Scaling Reference Resource) in [%].

The 2 types of reference inputs are combined in the following formula:

Remote reference=X+X*Y/100%.

If relative reference is not used, set parameter 3-18 Relative Scaling Reference Resource to [0] No function and parameter 3-14 Preset Relative Reference to 0%. The digital inputs on the frequency converter can activate both the catch up/slow down function and the freeze reference function. The functions and parameters are described in the VLT® Midi Drive FC 280 Programming Guide.

The scaling of analog references is described in parameter groups 6-1* Analog Input 53 and 6-2* Analog Input 54, and the scaling of digital pulse references is described in parameter group 5-5* Pulse Input.

Reference limits and ranges are set in parameter group 3-0* Reference Limits.

2.4.1 Reference Limits

Parameter 3-00 Reference Range, parameter 3-02 Minimum						2		2
Reference, and parameter 3-03 Maximum Reference de€ne
the allowed range of the sum of all references. The sum of
all references is clamped when necessary. The relation
between the resulting reference (after clamping) and the
sum of all references are shown in Illustration 2.15 and
Illustration 2.16.
P 3-00 Reference Range= [0] Min-Max				<![if ! IE]> <![endif]>130BA184.10
Resulting reference
P 3-03
			Forward
P 3-02
				Sum of all
				references
-P 3-02
			Reverse
-P 3-03

Illustration 2.15 Sum of All References When Reference Range is Set to 0

P 3-00 Reference Range =[1]-Max-Max

Resulting reference

<![if ! IE]>

<![endif]>130BA185.10

P 3-03

Sum of all references

-P 3-03

Illustration 2.16 Sum of All References When Reference Range is Set to 1

The value of parameter 3-02 Minimum Reference cannot be set to less than 0, unless parameter 1-00 Con‚guration Mode is set to [3] Process. In that case, the following relations between the resulting reference (after clamping) and the sum of all references are as shown in

Illustration 2.17.

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Product Overview

VLT® Midi Drive FC 280

P 3-00 Reference Range= [0] Min to Max

2	2	Resulting reference

	P 3-03
	P 3-02	Sum of all
		references

<![if ! IE]>

<![endif]>130BA186.11

2.4.3Scaling of Analog and Pulse References and Feedback

References and feedback are scaled from analog and pulse inputs in the same way. The only difference is that a reference above or below the speci€ed minimum and maximum endpoints (P1 and P2 in Illustration 2.18) are clamped while feedbacks above or below are not.

Resource output					<![if ! IE]> <![endif]>130BD431.10
[Hz]
High reference/
feedback value 50			P2

Illustration 2.17 Sum of All References When Minimum Reference is Set to a Minus Value

2.4.2Scaling of Preset References and Bus References

Preset references are scaled according to the following rules:

•When parameter 3-00 Reference Range is set to [0] Min–Max, 0% reference equals 0 [unit] where unit can be any unit, for example RPM, m/s, and bar.

100% reference equals the maximum (absolute value of parameter 3-03 Maximum Reference, absolute value of parameter 3-02 Minimum Reference).

•When parameter 3-00 Reference Range is set to [1] -Max–+Max, 0% reference equals 0 [unit], and 100% reference equals maximum reference.

Bus references are scaled according to the following rules:

•When parameter 3-00 Reference Range is set to [0] Min–Max, 0% reference equals minimum reference and 100% reference equals maximum reference.

•When parameter 3-00 Reference Range is set to [1] -Max–+Max, -100% reference equals -maximum reference, and 100% reference equals maximum reference.

	Low reference/	P1
	feedback value				Resource input
								[V]
	0	1		8		10

Terminal X high

Illustration 2.18 Minimum and Maximum Endpoints

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The endpoints P1 and P2 are de€ned in Table 2.5 depending on the choice of input.

								2		2
Input	Analog 53		Analog 54	Analog 54	Pulse input 29	Pulse input 33
	voltage mode		voltage mode	current mode
P1=(Minimum input value, minimum reference value)
Minimum reference value	Parameter 6-14 Te		Parameter 6-24 Te	Parameter 6-24 Ter	Parameter 5-52 Ter	Parameter 5-57 Term. 33
	rminal 53 Low		rminal 54 Low	minal 54 Low Ref./	m. 29 Low Ref./	Low Ref./Feedb. Value
	Ref./Feedb. Value		Ref./Feedb. Value	Feedb. Value	Feedb. Value
Minimum input value	Parameter 6-10 Te		Parameter 6-20 Te	Parameter 6-22 Ter	Parameter 5-50 Ter	Parameter 5-55 Term. 33
	rminal 53 Low		rminal 54 Low	minal 54 Low	m. 29 Low	Low Frequency [Hz]
	Voltage [V]		Voltage [V]	Current [mA]	Frequency [Hz]
P2=(Maximum input value, maximum reference value)
Maximum reference value	Parameter 6-15 Te		Parameter 6-25 Te	Parameter 6-25 Ter	Parameter 5-53 Ter	Parameter 5-58 Term. 33
	rminal 53 High		rminal 54 High	minal 54 High Ref./	m. 29 High Ref./	High Ref./Feedb. Value
	Ref./Feedb. Value		Ref./Feedb. Value	Feedb. Value	Feedb. Value
Maximum input value	Parameter 6-11 Te		Parameter 6-21 Te	Parameter 6-23 Ter	Parameter 5-51 Ter	Parameter 5-56 Term. 33
	rminal 53 High		rminal 54 High	minal 54 High	m. 29 High	High Frequency [Hz]
	Voltage [V]		Voltage [V]	Current [mA]	Frequency [Hz]

Table 2.5 P1 and P2 Endpoints

2.4.4 Dead Band Around Zero

Sometimes, the reference (in rare cases also the feedback) should have a dead band around 0 to ensure that the machine is stopped when the reference is near 0.

To make the dead band active and to set the amount of dead band, do the following:

•Set either the minimum reference value (see Table 2.5 for relevant parameter) or maximum reference value at 0. In other words, either P1 or P2 must be on the X-axis in Illustration 2.19.

•Ensure that both points de€ning the scaling graph are in the same quadrant.

P1 or P2 de€nes the size of the dead band as shown in Illustration 2.19.

	Quadrant 2	Resource output	Quadrant 1
		[Hz] or “No unit”
	High reference/feedback 50		P2
	value		forward

<![if ! IE]>

<![endif]>130BD446.10

	P1		Resource input
Low reference/feedback	0
			20 [mA]
value	1	16
	Terminal	Terminal X high
		low

	-50	reverse
Quadrant 3		Quadrant 4

Illustration 2.19 Size of Dead Band

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			Product Overview	VLT® Midi Drive FC 280
			Case 1: Positive reference with dead band, digital input to trigger reverse, part I
			Illustration 2.20 shows how reference input with limits inside minimum to maximum limits clamps.
2		2		General Reference		General Motor
				parameters:	Limited to: -200%- +200%	parameters:
				Reference Range: Min - Max		Motor speed direction:Both directions
					(-40 Hz- +40 Hz)
				Minimum Reference: 0 Hz (0,0%)		Motor speed Low limit: 0 Hz
				Maximum Reference: 20 Hz (100,0%)		Motor speed high limit: 8 Hz

	Analog input 53		Ext. reference	Reference
	Low reference 0 Hz	+			Limited to:
			Range:	algorithm
	High reference 20 Hz				0%- +100%
	Low voltage 1 V		0.0% (0 Hz)
Ext. Reference					(0 Hz- +20 Hz)
	High voltage 10 V		100.0% (20 Hz)
Absolute
0 Hz 1 V	Ext. source 1
20 Hz 10V				Reference
	Range:
				Range:
	0.0% (0 Hz)		Reference is scaled
				0.0% (0 Hz)
	100.0% (20 Hz)		according to min
				100.0% (20 Hz)
			max reference giving a
			speed.!!!		Dead band

Hz

20

Hz

Scale to

V

speed

20

1

10

V

1

10

Speed

setpoint

Range:

-20

Digital input 19

-20 Hz

Digital input

Low No reversing

+20 Hz

High Reversing

Limits Speed Setpoint

according to min max speed.!!!

	Motor PID
	Motor	Range:	Motor
		-8 Hz
	control
		+8 Hz

Illustration 2.20 Clamping of Reference Input with Limits inside Minimum to Maximum

<![if ! IE]>

<![endif]>130BD454.10

26

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MG07B302

Product Overview	Design Guide

Case 2: Positive reference with dead band, digital input to trigger reverse, part II

Illustration 2.21 shows how reference input with limits outside -maximum to +maximum limits clamps to the input low and

high limits before adding to external reference, and how the external reference is clamped to -maximum to +maximum by 2 2 the reference algorithm.

Ext. Reference

Absolute

0 Hz 1 V

30 Hz 10 V

Digital input

	General Reference		General Motor
	parameters:	Limited to: -200%- +200%	parameters:
	Reference Range: -Max - Max		Motor speed direction: Both directions
		(-40 Hz- +40 Hz)
	Minimum Reference: Don't care		Motor speed Low limit: 0 Hz
	Maximum Reference: 20 Hz (100.0%)		Motor speed high limit: 10 Hz

Analog input 53

Low reference 0 Hz High reference 20 Hz Low voltage 1 V High voltage 10 V

Ext. source 1

Range:

0.0% (0 Hz)

150.0% (30 Hz)

30 Hz

V

1 10

Digital input 19

Low No reversing High Reversing

+

Ext. reference

Reference

Limited to:

Range:

algorithm

-100%- +100%

0.0% (0 Hz)

(-20 Hz- +20 Hz)

150.0% (30 Hz)

Reference

Reference is scaled

Range:

0.0% (0 Hz)

according to

max reference giving a

100.0% (20 Hz)

speed.!!!

Dead band

Scale to

20 Hz

speed

V

1

10

Speed

setpoint

Range:

-20 Hz

-20 Hz

+20 Hz

Limits Speed Setpoint

according to min max speed.!!!

	Motor PID
	Motor	Range:	Motor
		–10 Hz
	control
		+10 Hz

<![if ! IE]>

<![endif]>130BD433.11

Illustration 2.21 Clamping of Reference Input with Limits outside -Maximum to +Maximum

MG07B302

Danfoss A/S © 05/2017 All rights reserved.

27

Product Overview VLT® Midi Drive FC 280

				2.5 PID Control
				2.5.1 Speed PID Control
2		2
				Parameter 1-00 Con€guration Mode	Parameter 1-01 Motor Control Principle
					U/f	VVC+
				[1] Speed closed loop	Not available1)	Active

Table 2.6 Control Configurations, Active Speed Control

1) Not available indicates that the speci‚c mode is not available at all.

Parameter	Description of function
Parameter 7-00 Speed PID Feedback Source	Select from which input the speed PID gets its feedback.
Parameter 7-02 Speed PID Proportional Gain	The higher the value, the quicker the control. However, too high a value may lead to
	oscillations.
Parameter 7-03 Speed PID Integral Time	Eliminates steady state speed error. Lower values mean quicker reaction. However, too low
	a value may lead to oscillations.
Parameter 7-04 Speed PID Di€erentiation Time	Provides a gain proportional to the rate of change of the feedback. A setting of 0 disables
	the differentiator.
Parameter 7-05 Speed PID Di€. Gain Limit	If there are quick changes in reference or feedback in a given application, which means
	that the error changes swiftly, the differentiator may soon become too dominant. This is
	because it reacts to changes in the error. The quicker the error changes, the stronger the
	differentiator gain is. The differentiator gain can thus be limited to allow setting of the
	reasonable differentiation time for slow changes and a suitably quick gain for quick
	changes.
Parameter 7-06 Speed PID Lowpass Filter Time	A low-pass €lter that dampens oscillations on the feedback signal and improves steady
	state performance. However, too long a €lter time deteriorates the dynamic performance of
	the speed PID control.
	Practical settings of parameter 7-06 Speed PID Lowpass Filter Time taken from the number of
	pulses per revolution on from encoder (PPR):
	Encoder PPR	Parameter 7-06 Speed PID Lowpass Filter
		Time
	512	10 ms
	1024	5 ms
	2048	2 ms
	4096	1 ms

Table 2.7 Speed Control Parameters

28

Danfoss A/S © 05/2017 All rights reserved.

MG07B302