Danfoss VLT Brake Resistor MCE 101 Design Manual

MAKING MODERN LIVING POSSIBLE

Design Guide

VLT® Brake Resistor MCE 101

VLT® Frequency Converters • FC 51 • FC 102 • FC 202 • FC 301 FC 302 • FC 360 • FCD 302 • VLT® 2800

www.danfoss.com/drives

Contents Design Guide

Contents

1 Introduction

1.1 How to Read this Design Guide

1.2 Conformity

1.3 Safety Precautions

1.4 Disposal

2 Product Overview

2.1 Description of the Brake System

2.2 Horizontal or Vertical Load

2.3 Aluminium-housed Brake Resistors

2.3.1 Aluminium-housed Flat-pack Brake Resistors 6

2.3.2 Aluminium-housed Compact Brake Resistor 6

2.4 Steel Grid Brake Resistors

3 Installation

3.1 Mechanical Installation

3.1.1 Aluminium-housed Compact Brake Resistors and Flat-pack Brake Resistors 7

3.1.2 Steel Grid Brake Resistors 10

4 4 4 4 4

5 5 5 6

6

7 7

3.1.3 Accessories 11

3.2 Electrical Installation

3.2.1 EMC Precautions 12

3.2.2 Cable Connection 12

3.2.3 Brake Cable 13

3.3 Protective Functions

3.3.1 Overtemperature Protection 13

3.3.2 Brake Resistor and Brake IGBT 14

4 System Integration

4.1 Brake Resistor Calculation

4.1.1 Brake Set-up 15

4.1.2 Calculation of Brake Resistor Resistance 15

4.1.3 Calculation of Braking Power 16

4.1.4 Calculation of the Brake Resistor Peak Power 17

4.1.5 Calculation of the Brake Resistor Average Power 17

4.1.6 Braking of Inertia 17

12

13

15 15

5 Programming

5.1 Parameters for VLT® Micro Drive FC 51

5.2 Parameters for VLT® HVAC Drive FC 102 and VLT® AQUA Drive FC 202

18

Contents Design Guide

5.3 Parameters for VLT® AutomationDrive FC 301/FC 302 and ® Decentral Drive FCD 302

21

5.4 Parameters for VLT® AutomationDrive FC 360

5.5 Parameters for VLT® 2800

6 Application Examples

6.1 Conveyor Belt

6.2 Centrifuge

6.3 Continuous Braking

7 Special Conditions

7.1 Alternative Braking Methods

7.1.1 DC Injection Braking 30

7.1.2 AC-braking 30

7.1.3 Mechanical Holding Brake 30

7.1.4 DC Braking 31

8 Selection Guide

8.1 Selection Flow Chart

8.2 Selection Tables for Recommended Brake Resistors

24

25

27 27 29 29

30 30

32 32 33

8.2.1 Abbreviations used in the Brake Resistor Tables 33

8.2.2 VLT® Micro Drive FC 51 33

8.2.3 VLT® HVAC Drive FC 102 35

8.2.4 VLT® AQUA Drive FC 202 41

8.2.5 VLT® AutomationDrive FC 301 48

8.2.6 VLT® AutomationDrive FC 302 51

8.2.7 VLT® AutomationDrive FC 360 57

8.2.8 VLT® Decentral Drive FCD 302 59

8.2.9 VLT® 2800 60

8.3 Selection Tables for Alternative Brake Resistors

8.3.1 Abbreviations used in the Brake Resistor Tables 62

8.3.2 VLT® HVAC Drive FC 102, T2 62

8.3.3 VLT® HVAC Drive FC 102, T4 62

8.3.4 VLT® AQUA Drive FC 202, T2 63

8.3.5 VLT® AQUA Drive FC 202, T4 63

8.3.6 VLT® AutomationDrive FC 301, T2 64

62

8.3.7 VLT® AutomationDrive FC 302, T2 64

8.3.8 VLT® AutomationDrive FC 301, T4 65

8.3.9 VLT® AutomationDrive FC 302, T5 65

9 Specifications

66

Contents Design Guide

9.1 Ambient Conditions

9.2 General Electrical Specifications

9.3 Electrical Data: MCE 101 Product Types 9xx

9.4 Mechanical Data: MCE 101 Product Types 9xx

9.5 Electrical Data: Product Types BWD and BWG

9.6 Mechanical Data: Product Types BWD and BWG

9.7 Mechanical Drawings

9.7.1 Figure 1 - 914CBT-HxxxDHT 83

9.7.2 Figure 2 - 914CBT-HxxxCHT 87

9.7.3 Figure 3 - 914CBT-HxxxBHT 90

9.7.4 Figure 4 - 914CBR-VxxxDT 93

9.7.5 Figure 5 - 914CBR-VxxxCT 96

9.7.6 Figure 6 - 914CBR-VxxxBT 98

9.7.7 Figure 7 - 914CCHxxxCT 101

9.7.8 Figure 8 - 917CM13 103

9.7.9 Figure 9 - 917CM15 105

9.7.10 Figure 10 - 917CM17 107

66 66 67 74 81 82 83

9.7.11 Figure 11 - 917CM25 109

9.7.12 Figure 12 - 917CM27 111

9.7.13 Figure 13 - 917CM37 113

9.7.14 Figure 14 - 917CMD27 115

9.7.15 Figure 15 - 917CMD37 117

9.7.16 Figure 16 - 929CBT-VxxxGHT 119

9.7.17 Figure 17 - 929CBT-VxxxBGHT 122

9.7.18 Figure 18 - 930CBT-VxxxGHT 125

9.7.19 Figure 19 - 930CBT- VxxxBGHT 128

9.7.20 Figure 20 - BWD250xxx 131

9.7.21 Figure 21 - BWD500xxx 132

9.7.22 Figure 22 - BWD600xxx 133

9.7.23 Figure 23 - BWG250xxx 135

9.7.24 Figure 24 - BWG500xxx 136

9.8 Mechanical Drawings: Accessories

9.8.1 Mounting Brackets: L Profile 137

9.8.2 Mounting Brackets: Footprint 139

137

Index

142

Introduction Design Guide

1

1 Introduction

1.1 How to Read this Design Guide

Danfoss VLT® Brake Resistors MCE 101 are optimised for:

VLT® Micro Drive FC 51

•

VLT® HVAC Drive FC 102

•

VLT® AQUA Drive FC 202

•

VLT® AutomationDrive FC 300

•

VLT® AutomationDrive FC 360

•

VLT® Decentral Drive FCD 302

•

VLT® 2800

•

General versions for horizontal and vertical applications are available.

The Design Guide provides the information required to select and plan installation of the right brake resistor for an application:

Selection of the correct brake resistor

•

Pre-installation considerations

•

Programming.

•

As an alternative to using a brake resistor, other braking methods can be applied depending on the braking profile of the application, see chapter 7 Special Conditions.

1.2

Conformity

Table 1.1 Approval

1) See Table 9.2 and Table 9.4 for UL conformity.

What is CE Conformity and Labelling

The purpose of CE labelling is to avoid technical trade obstacles within EFTA and the EU. The EU has introduced the CE label as a simple way of showing whether a product complies with the relevant EU directives. The CE label says nothing about the specifications or quality of the product. Brake resistors are regulated by the following EU directive:

The low-voltage directive (2006/95/EC)

Brake resistors must be CE labelled in accordance with the low-voltage directive of December 12, 2006. The directive applies to all electrical equipment and appliances used in the 50-1000 V AC and the 75-1500 V DC voltage ranges. Danfoss CE-labels in accordance with the directive and issues a declaration of conformity upon request.

1.3

Safety Precautions

1)

Additional technical literature is also available online at

www.danfoss.com/BusinessAreas/DrivesSolutions/Documentations/Technical+Documentation.

WARNING

When in use, the brake resistor surface temperature rises. DO NOT touch the brake resistor during operation.

WARNING

Never work on a brake resistor in operation.

NOTICE

Never attempt to repair a defective brake resistor.

1.4 Disposal

Equipment containing electrical components may not be disposed of together with domestic waste. It must be separately collected with electrical and electronic waste according to local and currently valid legislation.

150/160%

175UA067.10

100%

150/160%

175UA068.10

Product Overview Design Guide

2 Product Overview

2.1 Description of the Brake System

2.2

Horizontal or Vertical Load

2 2

When the speed reference of a frequency converter is reduced, the motor acts as a generator and the frequency converter brakes. When a motor acts as a generator, it supplies energy to the frequency converter which is collected in the DC link. The function of the brake resistor is to provide a load on the DC link during braking, thereby ensuring that the braking power is absorbed by the brake resistor.

If a brake resistor is not used, the DC-link voltage of the frequency converter continues to increase, until disconnecting for protection. The advantage of using a brake resistor is that it enables braking of a heavy load quickly, e.g. on a conveyor belt.

The brake resistors in this series are all external components. Therefore, the brake resistor does not form an integral part of the frequency converter. The external brake resistor provides the following advantages:

The resistor time cycle can be selected as

•

required. The heat developed during braking can be

•

conveyed beyond the panel cabinet to allow the energy to be used.

The electronic components do not overheat, even

•

when the brake resistor is overloaded.

The brake resistor series is suitable for Danfoss frequency converters

VLT® Micro Drive FC 51

•

VLT® HVAC Drive FC 102

•

VLT® AQUA Drive FC 202

•

VLT® AutomationDrive FC 300

•

VLT® AutomationDrive FC 360

•

VLT® Decentral Drive FCD 302

•

VLT® 2800

•

.

2.2.1 How to Select

The Danfoss brake resistor range consists of 2 groups:

Brake resistors for horizontal loads (conveyors,

•

trolleys, gantry cranes, etc.), see Illustration 2.1; Brake resistors for vertical loads (cranes, hoists,

•

elevators), see Illustration 2.2.

Illustration 2.1 Horizontal Loads

Illustration 2.2 Vertical Loads

The brake resistor range is intended to cover the general braking requirements for horizontal and vertical brake applications. To select the best brake resistor for an application, refer to chapter 8.1 Selection Flow Chart. The flow chart links to further information, either selection tables or calculations of inertia or duty cycle.

To cater for both the horizontal and vertical ranges, 3 types of brake resistors are available:

Aluminium-housed flat-pack brake resistors

•

Aluminium-housed compact brake resistors

•

Steel grid brake resistors

•

130BD245.12

1

130BD646.10

130BD228.10

130BD217.10

130BD586.10

Product Overview Design Guide

2.3 Aluminium-housed Brake Resistors

2.3.1 Aluminium-housed Flat-pack Brake

22

Resistors

The flat-pack brake resistor is an anodized aluminiumhoused resistor suitable for wall mounting or on a footprint or an L-profile bracket. The L-profile bracket is used for rear mounting. The brake resistor is designed for high pulse loads of up to 40 times the nominal load and is therefore suitable for both vertical and horizontal applications. The enclosure protection is IP54 or IP65.

Illustration 2.5 CBR-V-DT IP21

Illustration 2.3 Flat-pack IP54

Aluminium-housed Compact Brake

2.3.2 Resistor

The compact brake resistor is housed in aluminium profiles with pre-mounted brackets for wall mounting. It is designed for high pulse loads of up to 60 times the nominal load and is therefore used for both horizontal and vertical loads. The enclosure protection class is either IP21, IP54 or IP65. The brake resistor IP classes IP21 and IP65 are equipped with a connection box containing cable glands and cable connection to the resistor and the temperature switch. IP54 versions have fixed unscreened cables.

Illustration 2.6 CBR-V-BT IP65

2.4 Steel Grid Brake Resistors

The steel grid brake resistor is steel grid housed and consists of multiple elements. This brake resistor is suitable for pulse loads between 10 and 20 times the nominal load, suitable for frequent braking applications such as cranes, hoists and elevators. It is supplied in an IP20 enclosure with cable glands and has a built-in temperature switch.

Illustration 2.4 CBR-V-CT IP54

Illustration 2.7 Steel Grid House IP20

130BD900.10

200 mm

Installation Design Guide

3 Installation

3.1 Mechanical Installation

The brake resistors are cooled by natural convection, and the specified minimum clearances must be observed to ensure efficient ventilation. The ventilation must be efficient enough to dispatch the regenerative power in the brake resistor.

NOTICE

When installing the brake resistor, ensure all precautions are in place to avoid the risk of overloading. Overloading can lead to a fire hazard due to the heat generated in the brake resistor. The brake resistor is very hot during or after braking. The brake resistor must be located in a secure environment to avoid fire risk.

Mount the brake resistor free of any combustible

•

materials at a well ventilated location. The MCE 101 brake resistors product type 9xx

•

contain a built-in temperature switch (for overtemperature protection purposes. See chapter 3.3 Protective Functions).

Vertical Mounting, IP54

For minimum clearances for vertical mounting for all aluminium-housed compact and flat-pack brake resistors, see Illustration 3.1 and Illustration 3.2.

3 3

Aluminium-housed Compact Brake

3.1.1 Resistors and Flat-pack Brake Resistors

The aluminium-housed compact and flat-pack brake resistors are designed for vertical mounting for optimum cooling performance. However, horizontal mounting is possible for both flat-pack and compact brake resistors. Derating with 20% is required when mounting the compact brake resistors horizontally. No derating for flatpacks are required. The enclosure protection of the IP21 types is reduced to IP20 when mounted horizontally.

NOTICE

All resistors are cooled by natural convection. To ensure sufficient airflow and cooling, follow minimum clearance in Illustration 3.1 to Illustration 3.8.

Illustration 3.1 Vertical Mounting, IP54 Versions with Fixed Cables

130BD901.10

200 mm

500 mm

200 mm

200 mm200 mm

130BD902.10

130BD903.10

500 mm

130BD904.10

200 mm

Installation Design Guide

For minimum clearances for horizontal mounting for all aluminium-housed compact and flat-pack brake resistors, IP54 versions (versions with fixed cables), see Illustration 3.4 (side view).

33

Illustration 3.4 Horizontal mounting, IP54 Versions with Fixed Cables

Vertical mounting, IP21 and IP65

For minimum clearances for vertical mounting for all aluminium-housed compact brake resistors, see Illustration 3.5 and Illustration 3.6.

Illustration 3.2 Vertical Mounting, IP54 Versions with Fixed Cables

Horizontal mounting, IP54

For minimum clearances for horizontal mounting for all aluminium-housed compact and flat-pack brake resistors, see Illustration 3.3 (top view).

Illustration 3.3 Horizontal mounting, IP54 Versions with Fixed Cables

Illustration 3.5 Vertical Mounting, IP21 and IP65 Versions with Connection Box

200 mm

500 mm

100 mm

130BD905.10

200 mm

100 mm

200 mm

130BD906.10

130BD907.10

500 mm

130BD227.11

Installation

Design Guide

Horizontal mounting, IP21 and IP65

For minimum clearances for horizontal mounting for all aluminium housed compact brake resistors, see Illustration 3.8 (side view).

3 3

Illustration 3.8 Horizontal Mounting, IP21 and IP65 Versions with Connection Box

Orientation, compact and flat-pack brake resistors

Illustration 3.6 Vertical Mounting, IP21 and IP65 Versions with Connection Box

Horizontal mounting, IP21 and IP65

For minimum clearances for horizontal mounting for all aluminium-housed compact brake resistors, see Illustration 3.7 (top view).

Illustration 3.7 Horizontal Mounting, IP21 and IP65 Versions with Connection Box

Illustration 3.9 Orientation of Compact and Flat-pack Brake Resistors

Derating with 20% is required when mounting the compact brake resistors horizontally. The enclosure protection of the IP21 types is reduced to IP20 when mounted horizontally.

130BD708.12

150 mm

500 mm

175Uxxxx

130BD884.10

175Uxxxx

130BD709.11

Installation Design Guide

3.1.2 Steel Grid Brake Resistors

The steel grid brake resistors are designed for horizontal mounting only.

33

NOTICE

All resistors are cooled by natural convection. To ensure sufficient airflow and cooling, follow minimum clearances in Illustration 3.10 and Table 3.3.

Illustration 3.10 Minimum Clearances of all Steel Grid Brake Resistors - Top View

Illustration 3.12 Orientation of Steel Grid Brake Resistors

Illustration 3.11 Minimum Clearances of all Steel Grid Brake Resistors - Side View

1

2

3

130BD595.10

130BD838.10

Installation

Design Guide

3.1.3 Accessories

Footprint brackets

The footprint bracket is an accessory used for mounting flat-pack brake resistors.

Use the footprint bracket to mount the brake resistor at the rear of the frequency converter. Once mounted, the combined brake resistor and frequency converter occupy the same space in the cabinet as the frequency converter alone.

For mechanical dimensions for footprint brackets, see chapter 9.8.2 Mounting Brackets: Footprint.

L profile brackets

The L profile bracket is an accessory used for mounting flat-pack brake resistors. The L profile brackets support both horizontally and vertically mounting on a fixed surface optimising the required footprint.

3 3

1 Frequency converter 2 Footprint mounting bracket 3 Flat-pack brake resistor

Illustration 3.13 Flat-pack Brake Resistor mounted at Rear of Frequency Converter

Part number Compatible brake resistor Compatible frequency

175U0085

175U0087

175U0086

175U0088

Table 3.1 Selection Table

1x100 W flat-pack 1x200 W flat-pack 2x100 W flat-pack 2x200 W flat-pack 2x100 W flat-pack 2x200 W flat-pack 1x100 W flat-pack 1x200 W flat-pack

converter enclosure size

A2

A3

Illustration 3.14 L Profile Bracket

Part number Compatible brake resistor

175U0009 1x200 W flat-pack

175U0011

Table 3.2

1) Order 2x175U0011 for 300 W flat-pack brake resistors.

1)

1x100 W flat-pack 1x300 W flat-pack

For mechanical dimensions for L profile brackets, see

chapter 9.8.1 Mounting Brackets: L Profile

Fieldbus cable

Min. 200 mm

90° crossing

Brake resistor

130BD507.11

130BB154.12

Installation Design Guide

3.2 Electrical Installation

Cable Connection

3.2.2

3.2.1 EMC Precautions

The following EMC precautions are recommended to achieve interference-free operation of fieldbus cable(s) and

33

digital and analog inputs and outputs.

NOTICE

To comply with EMC emission specifications, screened/ armoured cables are recommended.

NOTICE

Observe relevant national and local regulations, for example regarding protective earth connection. Keep the fieldbus cable(s) away from motor and brake resistor cables to avoid coupling of high frequency noise from one cable to another. Normally, a distance of 200 mm (8 inches) is sufficient, but keeping the greatest possible distance between the cables is recommended, especially where cables run in parallel over long distances. When crossing is unavoidable, the fieldbus cable(s) must cross motor and brake resistor cables at an angle of 90°, see Illustration 3.15.

Cables General: All cabling must comply with national and local regulations on cable cross-sections and ambient temperature.

See Table 3.3 for recommended temperature ratings for all cables and conductors connected to the brake resistor as ground connection, thermal switch and brake power.

IP class Recommended cables

IP20 IP21 IP54 IP65

Table 3.3 Cable Temperature Ratings

1) For ground connection

How to connect more than one resistor

Star parallel connection to ensure load is shared evenly between 2 or more resistors.

≥80 °C ≥80 °C ≥90 °C ≥90 °C

1)

Illustration 3.15 Cable Routing

Illustration 3.16 Connection of Several Brake Resistors

81

82

99

91 92 93 95

96 97 98 99

12

18

L1 L2 L3 PE

U V W PE

VLT

MCE 101

Brake resistor

T1

T2

RB1

RB2

L1 L2 L3 PE

F1

PE

R-

R+

PE

+24V

D-in

M

3~

130BD553.11

Installation

Design Guide

Brake resistors with fixed cables

To reduce the electrical noise from the wires between the brake resistor and the frequency converter, twist the wires. For enhanced EMC performance a metal screen can be used.

Illustration 3.17 Twisted Cables

Brake Cable

3.2.3

Max. length: 20 m shielded cable.

Automatic restart after enabling of the temperature switch:

Select coast inverse for the selected digital input.

Prevent automatic restart:

Select latched start for the selected digital input.

NOTICE

Coast does not terminate the brake function.

Example 1

3 3

Ensure the connection cable to the brake resistor is shielded. Connect the shielding to the conductive back plate of the frequency converter and to the brake resistor metal cabinet, using cable clamps.

3.3

Protective Functions

3.3.1 Overtemperature Protection

The Danfoss brake resistor MCE 101 is equipped with a galvanic isolated temperature switch (PELV) that is closed under normal operating conditions and open if the brake resistor is overheated.

NOTICE

Use the temperature switch as overtemperature protection feature to prevent damage of the brake resistor caused by overtemperature. To prevent damage to the brake resistor, perform an immediate stop or a ramp down.

There are several ways the temperature switch can be used:

The temperature switch as digital input to frequency converter Example 1

1. Connect terminal T1 of the brake resistor to the frequency converter terminal 12 or 13.

2. Connect terminal T2 of the brake resistor to a digital input e.g. terminal 18.

Illustration 3.18 Temperature Switch in Brake Resistor

NOTICE

The temperature switch as input to the frequency converter cannot be considered a primary safety function. In case of a malfunction in the brake IGBT, the frequency converter and brake resistor are only protected by disconnecting the mains supply to the frequency converter. The temperature switch must be connected disabling the mains supply to the frequency converter by a contactor preventing dangerous overtemperatures.

91 92 93 95

96 97 98 99

M

3~

12

27

L1 L2 L3 PE

VLT

MCE 101

Brake resistor

T1

T2

RB1

RB2

99

PE

81

R -

82R+

PE

L1 L2 L3

N

PE

F1

S1 K1

F2

S2

K1

U V W PE

130BD554.11

Installation Design Guide

The temperature switch disabling the mains supply to

3.3.2

Brake Resistor and Brake IGBT

VLT by a contactor Example 2

1. Connect the brake resistor built-in thermal switch as controlling an input contactor. In this example, the thermal switch within the brake resistor is

33

connected in series with the thermal switch within the motor.

2. Connect start and stop push buttons in series with the thermal switches.

3. Connect to a contactor in the mains supply in front of the frequency converter.

Thermal overheating in brake resistor or motor disables the mains supply to the frequency converter.

Example 2

Brake resistor power monitor

In addition, the brake power monitor function makes it possible to read out the momentary power and the mean power for a selected time period. The brake can also monitor the power energising and make sure it does not exceed a limit selected in parameter 2-12 Brake Power Limit (kW). In 2-13 Brake Power Monitoring, select the function to carry out when the power transmitted to the brake resistor exceeds the limit set in parameter 2-12 Brake Power Limit (kW).

NOTICE

Monitoring the brake power does not fulfil a safety function. The brake resistor circuit is not ground leakage protected.

The brake is protected against short-circuiting of the brake resistor, and the brake transistor is monitored to ensure that short-circuiting of the transistor is detected. Use a relay or digital output to protect the brake resistor against overloading in the event of a fault in the frequency converter, see chapter 3.3.1 Overtemperature Protection.

Illustration 3.19 Temperature Switch in both Motor and Brake Resistor disabling Mains Supply by an Input Contactor

Thermo relay disabling the brake resistor Example 3

Calculate the brake current (I

thermo relay

) setting of the

temperature switch as follows:

P

I

thermo relay

brake resistor max

=

R

br

Rbr is the current brake resistor value calculated in chapter 4.1.2 Calculation of Brake Resistor Resistance.

Look up the brake current setting of the thermo relay for Danfoss brake resistors in chapter 8 Selection Guide.

Overvoltage control (OVC) can be selected as an alternative brake function in parameter 2-17 Over-voltage Control. If the DC-link voltage increases, this function is active for all units. The function ensures that a trip can be avoided. This is done by increasing the output frequency to limit the voltage from the DC link. It is a useful function, e.g. if the ramp-down time is too short since tripping of the frequency converter is avoided. In this situation the rampdown time is extended.

P

peak,mec.

175ZA096.14

VLT

U

DC

I

termo

P

peak

P

avg

R

br

P

b, max

P

motor

η

INV

= 0.98

η

motor

= 0.9

System Integration

4 System Integration

Design Guide

4.1 Brake Resistor Calculation

To ensure the optimal selection of brake resistor for a given application, its inertia and braking profile calculations are required. This chapter explains the calculations required to obtain values for optimal selection of brake resistor for a given application.

4.1.1 Brake Set-up

The following sections use expressions and abbreviations related to the brake set-up in Illustration 4.1.

Udc is the voltage, where the brake is activated. The FCseries brake function is settled depending on the mains supply.

DC-link Voltage (Udc), FC 51

Size [V] Brake active

[V]

FC 51 1x200-240 390 410 410 FC 51 3x200-240 390 410 410 FC 51 3x380-480,

1.5-4.0 kW FC 51 3x380-480,

5.5-15 kW FC 51 3x380-480,

18.5-22 kW

Table 4.1 DC-link Voltage (Udc), FC 51

1) Adjustable with 2-14 Brake Voltage Reduce

770 800 800

705-770

770 800 800

1)

Warning before cut out [V]

800 800

Cut out (trip) [V]

DC-link Voltage (Udc), FC 102

Brake

Size [V]

FC 102 3x200-240 390 405 410 FC 102 3x380-480 778 810 820 FC 102 3x525-600 FC 102 3x525-600 FC 102 3x525-690 1099 1109 1130

1)

2)

active

[V DC]

943 965 975

1099 1109 1130

High

voltage

warning

[V DC]

Over

voltage

alarm

[V DC]

4 4

Table 4.2 DC-link Voltage (Udc), FC 102

1) Enclosure types A, B, C

2) Enclosure types D, E, F

Illustration 4.1 Brake Set-up

Calculation of Brake Resistor

4.1.2 Resistance

To prevent the frequency converter from cutting out for protection when the motor brakes, select resistor values on the basis of the peak braking power and the intermediate circuit voltage:

2

Udc

R

=

br

P

peak

Ω

The brake resistor performance depends on the DC-link voltage (Udc).

DC-link Voltage (Udc), FC 202

Brake

Size [V]

FC 202 3x200-240 390 405 410 FC 202 3x380-480 778 810 820 FC 202 3x525-600 FC 202 3x525-600 FC 202 3x525-690 1099 1109 1130

Table 4.3 DC-link Voltage (Udc), FC 202

1) Enclosure types A, B, C

2) Enclosure types D, E, F

1)

2)

active

[V DC]

943 965 975

1099 1109 1130

High

voltage

warning

[V DC]

Over

voltage

alarm

[V DC]

P [W]

P

peak

P

avg

T

p

T

b

t [s]

175ZA094.13

System Integration Design Guide

DC-link Voltage (Udc), FC 301/FC 302

Use the brake resistance R

, to ensure that the frequency

rec

converter is able to brake at the highest braking torque

High

voltage

warning

[V DC]

Size [V]

FC 301 3x200-240 FC 301 3x200-240

Brake active

[V DC]

1)

2)

365 405 410 390 405 410

FC 302 3x200-240 390 405 410

44

FC 301 3x380-480 FC 301 3x380-480 FC 302 3x380-500 FC 302 3x380-500 FC 302 3x525-600 FC 302 3x525-600

1)

2)

3)

4)

3)

4)

728 810 820 778 810 820 810 840 855 810 828 855 943 965 975

1099 1109 1130

FC 302 3x525-690 1099 1109 1130

Table 4.4 DC-link Voltage (Udc), FC 301/FC 302

1) Enclosure type A

2) Enclosure types B, C

3) Enclosure types A, B, C

4) Enclosure types D, E, F

DC-link Voltage (Udc), FC 360

1)

High

voltage

warning

[V DC]

800 800

Size [V]

FC 360 3x380-480,

0.37-22 kW FC 360 3x380-480, 30-75 kW

Brake active

[V DC]

700-770

N/A

2)

Over

voltage

alarm

[V DC]

Over

voltage

alarm

[V DC]

(M

) (e.g. 160%). The formula is written as:

br(%)

2

U

x 100

R

Ω =

η η

rec

motor

VLT

P

motor

is typically at 0.90

is typically at 0.98

x

dc

M

x η

br

%

VLT

x η

motor

When a higher brake resistor resistance is selected, 160%/ 150%/110% braking torque cannot be obtained, and there is a risk that the frequency converter cuts out of DC-Link overvoltage for protection.

For braking at lower torque, for example 80% torque, it is possible to install a brake resistor with lower power rating. Calculate size using the formula for calculating R

Calculation of Braking Power

4.1.3

rec

.

When calculating the braking power, ensure that the brake resistor is scaled for the average power as well as the peak power.

The average power is determined by the process

•

period time, i.e. the length of the braking time in relation to the process period time.

The peak power is determined by the braking

•

torque, which means that as braking progresses, the brake resistor must be able to dissipate the energy input.

Illustration 4.2 shows the relation between the average

Table 4.5 DC-link Voltage (Udc), FC 360

1) Adjustable with 2-14 Brake voltage reduce

2) No built-in brake option

power and the peak power.

DC-link Voltage (Udc), FCD 302

High

voltage

warning

[V DC]

Size [V]

Brake active

[V DC]

FCD 302 3x380-480 778 810 820

Table 4.6 DC-link Voltage (Udc), FCD 302

DC-link Voltage (Udc), VLT 2800

Brake

Size [V]

active

[V DC]

VLT 2800 3x200-240 385 400 410 VLT 2800 3x380-480 770 800 820

Table 4.7 DC-link Voltage (Udc), VLT 2800

High

voltage

warning

[V DC]

Over

voltage

alarm

[V DC]

Over

voltage

alarm

[V DC]

T

p

T

b

Process period time in s Braking time in s

Illustration 4.2 Relation between Average Power and Peak Power

ω Start

ω Stop

∆t

∆ω/∆t

175ZA863.11

System Integration

Design Guide

4.1.4 Calculation of the Brake Resistor Peak Power

P the motor shaft. Calculate P

P

P when the motor brakes.

P the efficiencies of the motor and the frequency converter.

Calculate P

P

When the brake resistor recommended by Danfoss is selected (R chapter 8 Selection Guide, the brake resistor is certain to provide a braking torque of 160%/150%/110% on the motor shaft.

is the peak power by which the motor brakes on

peak, mec

as follows:

peak, mec

=

P

×

M

peak, mec

is the braking power dissipated to the brake resistor

peak

is lower than P

peak

=

peak

motor

peak,mec

as follows:

peak

P

×

M

motor

) on the basis of the tables in

rec

BR %

×

W

BR %

since the power is reduced by

η

×

η

W

VLT

motor

Danfoss offers brake resistors with a duty-cycle of max. 10% and 40%. If a 10% duty-cycle is applied, the brake resistors are able to absorb P

for 10% of the period

peak

time. The remaining 90% of the period time is used on deflecting excess heat.

Calculate the average power with 10% duty-cycle as follows:

P

=

P

avg

peak

× 10 %

W

Calculate the average power with 40% duty-cycle as follows:

P

=

P

avg

peak

× 40 %

W

The calculations apply to intermittent braking using a period time of 30 s.

NOTICE

Exceeding the specified intermittent braking period time may result in overheating the resistor.

4 4

Calculation of the Brake Resistor

4.1.5 Average Power

The average power is determined by the length of the braking time in relation to the process period time.

When the kinetic energy (Eb) transferred to the resistor in each braking sequence is known (see chapter 6.1 Conveyor Belt and chapter 6.2 Centrifuge), calculate the average power of the brake resistor as follows:

E

avg

b

=

W

T

p

T

× 100

b

%

T

p

Tp = process period time in s Tb = braking time in s

P

Tp = period time in s, see Illustration 4.2.

When the kinetic energy transferred to the resistor in each braking sequence is not known, calculate the average power on the basis of the process period time and the braking time.

Calculate the duty-cycle for the braking sequence as follows:

Duty cycle =

where

4.1.6 Braking of Inertia

When braking high inertia values on the motor shaft, base the brake resistor values on the inertia, Δω, Δt, see Illustration 4.3.

Illustration 4.3 Braking of High Inertia

Δt is determined by the ramp-down time.

NOTICE

The ramp-down time goes from the rated motor frequency to 0 Hz.

P

can be calculated as:

peak

P

=

η

×

η

×

ω

VLT

η

×

n

start

VLT

P

peak

=

motor

η

motor

×

j is the motor shaft inertia.

start

×

× j ×

j

×

2 ×

Δω

60

Δt

Δn

π

2

×

Δt

Programming Design Guide

5 Programming

For descriptions of all available parameters, see the product specific Programming Guide, www.danfoss.com/

BusinessAreas/DrivesSolutions/Documentations/VLT+Technical +Documentation.htm.

5.1

Parameters for VLT® Micro Drive FC 51

2-10 Brake Function

55

Option: Function:

NOTICE

Resistor brake is only functional in frequency converters with integrated dynamic brake. An external resistor must be connected.

Resistor Brake

The resistor brake limits voltage in the intermediate circuit when the motor acts as generator. Without brake resistor, the frequency converter eventually trips. The resistor brake consumes surplus energy resulting from motor braking. A frequency converter with brake, stops a motor faster than without a brake, which is used in many applications. Requires connection of external brake resistor. An alternative to the resistor brake is the AC brake.

AC Brake

The AC brake consumes surplus energy by creating power loss in the motor. It is important to keep in mind that an increase in power loss causes motor temperature to rise.

* Off No brake function.

[0] [1] Resistor

Brake

[2] AC Brake AC brake is active.

Resistor brake is active.

5.2

Parameters for VLT® HVAC Drive FC 102 and VLT® AQUA Drive FC 202

2-02 DC Braking Time

Range: Function:

10 s* [0 - 60 s] Set the duration of the DC braking current set

in 2-01 DC Brake Current, once activated.

2-03 DC Brake Cut In Speed [RPM]

Range: Function:

Size related*

[ 0 - 0 RPM]

Set the DC brake cut-in speed to activate the DC braking current set in 2-01 DC Brake Current, upon a stop command.

When 1-10 Motor Construction is set to [1] PM non-salient SPM this value is limited to 0 RPM (OFF)

NOTICE

Parameter 2-03 DC Brake Cut In Speed [RPM] does not have effect when 1-10 Motor Construction=[1] PM, nonsalient SPM.

2-04 DC Brake Cut In Speed [Hz]

Range: Function:

Size related* [ 0 - 1000.0

Hz]

Set the DC brake cut-in speed for activation of the DC braking current set in 2-01 DC Brake Current, upon a stop command.

NOTICE

Parameter 2-04 DC Brake Cut In Speed [Hz] has no effect

when 1-10 Motor Construction[1] PM, non-salient SPM.

2-11 Brake Resistor (Ohm)

Range: Function:

5 Ω* [5-5000 Ω] Set brake resistor value.

2-14 Brake Voltage Reduce

Range: Function:

0 V* [ 0 - 0 V]

Programming Design Guide

2-10 Brake Function

Option: Function:

Available selections depend on 1-10 Motor Construction:

[0] Asynchron:

[0] Off

•

[1] Resistor brake

•

[2] AC brake

•

[1] PM non-salient:

[0] Off

•

[1] Resistor brake

•

[0] Off No brake resistor installed.

[1] Resistor

brake

[2] AC brake AC Brake only works in Compressor Torque mode

Brake resistor incorporated in the system, for dissipation of surplus brake energy as heat. Connecting a brake resistor allows a higher DClink voltage during braking (generating operation). The resistor brake function is only active in frequency converters with an integral dynamic brake.

in 1-03 Torque Characteristics.

2-11 Brake Resistor (ohm)

Range: Function:

Size related*

[ 5.00 -

65535.00 Ohm]

Set the brake resistor value in Ω. This value is used for monitoring the power to the brake resistor in 2-13 Brake Power Monitoring. This parameter is only active in frequency converters with an integral dynamic brake. Use this parameter for values without decimals. For a selection with 2 decimals, use parameter 30-81 Brake Resistor (ohm).

2-12 Brake Power Limit (kW)

Range: Function:

Size related*

[ 0.001 -

2000.000 kW]

Parameter 2-12 Brake Power Limit (kW) is the expected average power dissipated in the brake resistor over the time period selected within 2-13 Brake Power Monitoring. It is used as the monitoring limit for 16-33 Brake Energy /2 min and thereby specifies when a warning/alarm is to be given. To calculate parameter 2-12 Brake Power Limit (kW), the following formula can be used.

2

U

V×tbrs

P

br,avg

P

br,avg

the brake resistor, Rbr is the resistance of the brake resistor. tbr is the active breaking time within the 120 s period, Tbr.

br

W

=

RbrΩ×Tbrs

is the average power dissipated in

2-12 Brake Power Limit (kW)

Range: Function:

Ubr is the DC voltage where the brake resistor is active.

NOTICE

If values are unknown, or if Tbr is different from 120 s, the practical approach is to run the brake application, readout 16-33 Brake Energy /2 min and then enter this +20% in 2-12 Brake Power Limit (kW).

2-13 Brake Power Monitoring

Option: Function:

This parameter is only active in frequency converters with an integral dynamic brake. This parameter enables monitoring of the power to the brake resistor. The power is calculated on the basis of the resistance (parameter 2-11 Brake Resistor (ohm)), the DC-link voltage, and the resistor duty time. The time periode can be selected in this parameter. The functions are as follows:

Off:

•

Brake power monitoring disabled. Default setting.

Warning (time period):

•

Activates a warning on the display when the power transmitted over the selected time period exceeds 100% of the monitoring limit (parameter 2-12 Brake Power Limit (kW)). The warning disappears when the transmitted power falls below 80% of the monitoring limit.

Trip (time period);

•

Trips frequency converter and displays an alarm when the calculated power exceeds 100% of the monitoring limit.

Warning & trip (time period):

•

Activates both of the above, including warning, trip and alarm.

* Disabled Brake power monitoring disabled.

[0] [1] Warning 120s Warning based on 120 s time periode. [2] Trip 120s Trip based on 120 s time periode. [3] Warning &

trip 120s [4] Warning 30s Warning based on 30 s time periode. [5] Trip 30s Trip based on 30s time periode

Warning and trip based on 120 s time periode.

5 5

Programming Design Guide

2-13 Brake Power Monitoring

Option: Function:

[6] Warning &

trip 30s [7] Warning 60s Warning based on 60 s time periode. [8] Trip 60s Trip based on 60 s time periode. [9] Warning &

trip 60s [10] Warning 300s Warning based on 300 s time periode. [11] Trip 300s Trip based on 300 s time periode. [12] Warning &

55

trip 300s [13] Warning 600s Warning based on 600s time periode. [14] Trip 600s Trip based on 600 s time periode. [15] Warning &

trip 600s

Warning and trip based on 30 s time periode.

Warning and trip based on 60 s time periode.

Warning and trip based on 300 s time periode.

Warning and trip based on 600 s time periode.

If power monitoring is disabled or Warning is selected, the brake function remains active, even if the monitoring limit is exceeded. This may lead to thermal overload of the resistor. It is also possible to generate a warning via a relay/digital outputs. The measuring accuracy of the power monitoring depends on the accuracy of the resistance of

2-15 Brake Check

Option: Function:

[2] Trip Monitors for a short-circuit or disconnection of

the brake resistor, or a short-circuit of the brake IGBT. If a fault occurs, the frequency converter cuts out while displaying an alarm (trip locked).

[3] Stop and

trip

[4] AC brake Monitors for a short-circuit or disconnection of

Monitors for a short-circuit or disconnection of the brake resistor, or a short-circuit of the brake IGBT. If a fault occurs, the frequency converter ramps down to coast and then trips. A trip lock alarm is displayed.

the brake resistor, or a short-circuit of the brake IGBT. If a fault occurs, the frequency converter performs a controlled ramp-down.

NOTICE

Remove a warning arising in connection with [0] Off or [1] Warning by cycling the mains supply. The fault must

be corrected first. For [0] Off or [1] Warning, the frequency converter keeps running even if a fault is located.

the resistor (better than ±20%).

2-15 Brake Check

Option: Function:

Select type of test and monitoring function to check the connection to the brake resistor, or whether a brake resistor is present, and then display a warning or an alarm in the event of a fault. The brake resistor disconnection function is tested during power-up. However, the brake IGBT test is performed when there is no braking. A warning or trip disconnects the brake function. The testing sequence is as follows:

1. The DC-link ripple amplitude is measured for 300 ms without braking.

2. The DC-link ripple amplitude is measured for 300 ms with the brake turned on.

3. If the DC-link ripple amplitude while braking is lower than the DC-link ripple amplitude before braking +1%. Brake check failed, return a warning or alarm.

4. If the DC-link ripple amplitude while braking is higher than the DC-link ripple amplitude before braking +1%. Brake check OK.

Off Monitors brake resistor and brake IGBT for a

[0]

*

[1] Warning Monitors brake resistor and brake IGBT for a

short-circuit during operation. If a short-circuit occurs, a warning appears.

short-circuit, and runs a test for brake resistor disconnection during power-up.

2-16 AC brake Max. Current

Range: Function:

100 %* [ 0 - 1000.0%]Enter the maximum permissible current

when using AC brake to avoid overheating of motor windings. The AC brake function is available in Flux mode only.

NOTICE

Parameter 2-16 AC brake Max. Current has no effect when 1-10 Motor Construction=[1] PM, non-salient SPM.

2-17 Over-voltage Control

Option: Function:

[0] Disabled No OVC required.

[2] * Enabled Activates OVC.

NOTICE

Parameter 2-17 Over-voltage Control has no effect when 1-10 Motor Construction[1] PM, non-salient SPM.

NOTICE

The ramp time is automatically adjusted to avoid tripping of the frequency converter.

Programming Design Guide

16-32 Brake Energy /s

Range: Function:

0 kW* [0 - 10000 kW] View the brake power transmitted to an

external brake resistor, stated as an instantaneous value.

16-33 Brake Energy /2 min

Range: Function:

0 kW* [0 - 10000

kW]

View the brake power transmitted to an external brake resistor. The mean power is calculated on an average level based on the selected time period within 2-13 Brake Power Monitoring.

30-81 Brake Resistor (ohm)

Range: Function:

Size related*

[ 0.01 -

65535.00 Ohm]

Set the brake resistor value in Ω with 2 decimals. This value is used for monitoring the power to the brake resistor in 2-13 Brake Power Monitoring.

5.3

Parameters for VLT® AutomationDrive FC 301/FC 302 and ® Decentral Drive

FCD 302

2-02 DC Braking Time

Range: Function:

10 s* [0 - 60 s] Set the duration of the DC braking current set

in 2-01 DC Brake Current, once activated.

2-03 DC Brake Cut In Speed [RPM]

Range: Function:

Size related* [ 0 - 60000

RPM]

2-04 DC Brake Cut In Speed [Hz]

Range: Function:

Size related* [ 0 - 1000.0

Hz]

Set the DC brake cut-in speed for activation of the DC braking current set in 2-01 DC Brake Current, upon a stop command.

5 5

NOTICE

Parameter 2-04 DC Brake Cut In Speed [Hz] has no effect

when 1-10 Motor Construction[1] PM, non-salient SPM.

2-10 Brake Function

Option: Function:

[0] Off No brake resistor is installed.

[1] Resistor

brake

[2] AC brake Is selected to improve braking without using a

A brake resistor is incorporated in the system, for dissipation of surplus brake energy as heat. Connecting a brake resistor allows a higher DClink voltage during braking (generating operation). The resistor brake function is only active in frequency converters with an integral dynamic brake.

brake resistor. This parameter controls an overmagnetisation of the motor when running with a generatoric load. This function can improve the OVC-function. Increasing the electrical losses in the motor allows the OVC function to increase the braking torque without exceeding the over voltage limit.

NOTICE

The AC brake is not as efficient as dynamic braking with resistor. AC brake is for VVC+ mode in both open and closed loop.

Programming

Design Guide

2-11 Brake Resistor (ohm)

Range: Function:

Size related*

55

2-12 Brake Power Limit (kW)

[ 5.00 -

65535.00 Ohm]

Set the brake resistor value in Ω. This value is used for monitoring the power to the brake resistor in 2-13 Brake Power Monitoring. This parameter is only active in frequency converters with an integral dynamic brake. Use this parameter for values without decimals. For a selection with 2 decimals, use parameter 30-81 Brake Resistor (ohm).

Range: Function:

Size related*

[ 0.001 -

2000.000 kW]

Parameter 2-12 Brake Power Limit (kW) is the expected average power dissipated in the brake resistor over the time period selected within 2-13 Brake Power Monitoring. It is used as the monitoring limit for 16-33 Brake Energy /2 min and thereby specifies when a warning/alarm is to be given. To calculate parameter 2-12 Brake Power Limit (kW), the following formula can be used.

2

U

V×tbrs

P

br,avg

P

br,avg

the brake resistor, Rbr is the resistance of the brake resistor. tbr is the active breaking time within the 120 s period, Tbr. Ubr is the DC voltage where the brake resistor is active.

br

W

=

RbrΩ×Tbrs

is the average power dissipated in

NOTICE

If values are unknown, or if Tbr is different from 120 s, the practical approach is to run the brake application, readout 16-33 Brake Energy /2 min and then enter this +20% in 2-12 Brake Power Limit (kW).

2-13 Brake Power Monitoring

Option: Function:

This parameter is only active in frequency converters with an integral dynamic brake. This parameter enables monitoring of the power to the brake resistor. The power is calculated on the basis of the resistance (parameter 2-11 Brake Resistor (ohm)), the DC-link voltage, and the resistor duty time. The time periode can be selected in this parameter. The functions are as follows:

2-13 Brake Power Monitoring

Option: Function:

Off:

•

Brake power monitoring disabled. Default setting.

Warning (time period):

•

Activates a warning on the display when the power transmitted over the selected time period exceeds 100% of the monitoring limit (parameter 2-12 Brake Power Limit (kW)). The warning disappears when the transmitted power falls below 80% of the monitoring limit.

Trip (time period);

•

Trips frequency converter and displays an alarm when the calculated power exceeds 100% of the monitoring limit.

Warning & trip (time period):

•

Activates both of the above, including warning, trip and alarm.

[0] * Disabled Brake power monitoring disabled. [1] Warning 120s Warning based on 120 s time periode. [2] Trip 120s Trip based on 120 s time periode. [3] Warning &

trip 120s [4] Warning 30s Warning based on 30 s time periode. [5] Trip 30s Trip based on 30s time periode [6] Warning &

trip 30s [7] Warning 60s Warning based on 60 s time periode. [8] Trip 60s Trip based on 60 s time periode. [9] Warning &

trip 60s [10] Warning 300s Warning based on 300 s time periode. [11] Trip 300s Trip based on 300 s time periode. [12] Warning &

trip 300s [13] Warning 600s Warning based on 600s time periode. [14] Trip 600s Trip based on 600 s time periode. [15] Warning &

trip 600s

Warning and trip based on 120 s time periode.

Warning and trip based on 30 s time periode.

Warning and trip based on 60 s time periode.

Warning and trip based on 300 s time periode.

Warning and trip based on 600 s time periode.

If power monitoring is disabled or Warning is selected, the brake function remains active, even if the monitoring limit is exceeded. This may lead to thermal overload of the resistor. It is also possible to generate a warning via a relay/digital outputs. The measuring accuracy of the power monitoring depends on the accuracy of the resistance of the resistor (better than ±20%).

Programming Design Guide

2-15 Brake Check

Option: Function:

Parameter 2-15 Brake Check is only active in frequency converters with an integral dynamic brake.

Select type of test and monitoring function to check the connection to the brake resistor, or whether a brake resistor is present, and then display a warning or an alarm in the event of a fault.

NOTICE

The brake resistor disconnection function is tested during power-up. However, the brake IGBT test is performed when there is no braking. A warning or trip disconnects the brake function.

The testing sequence is as follows:

1. The DC-link ripple amplitude is measured for 300 ms without braking.

2. The DC-link ripple amplitude is measured for 300 ms with the brake turned on.

3. If the DC-link ripple amplitude while braking is lower than the DC-link ripple amplitude before braking + 1%: Brake

check has failed by returning a warning or alarm.

4. If the DC-link ripple amplitude while braking is higher than the DC-link ripple amplitude before braking + 1%: Brake

check is OK.

Off Monitors brake resistor and brake IGBT for a

[0]

*

[1] Warning Monitors brake resistor and brake IGBT for a

[2] Trip Monitors for a short-circuit or disconnection of

[3] Stop and

trip

[4] AC brake Monitors for a short-circuit or disconnection of

short-circuit during operation. If a short-circuit occurs, warning 25 appears.

short-circuit, and runs a test for brake resistor disconnection during power-up.

the brake resistor, or a short-circuit of the brake IGBT. If a fault occurs, the frequency converter cuts out while displaying an alarm (trip locked).

Monitors for a short-circuit or disconnection of the brake resistor, or a short-circuit of the brake IGBT. If a fault occurs, the frequency converter ramps down to coast and then trips. A trip lock alarm is displayed (e.g. warning 25, 27 or 28).

the brake resistor, or a short-circuit of the brake IGBT. If a fault occurs, the frequency converter performs a controlled ramp-down. This option is available for FC 302 only.

2-15 Brake Check

Option: Function:

[5] Trip Lock

NOTICE

Remove a warning arising in connection with [0] Off or [1] Warning by cycling the mains supply. The fault must

be corrected first. For [0] Off or [1] Warning, the frequency converter keeps running even if a fault is located.

2-16 AC brake Max. Current

Range: Function:

100 %* [ 0 - 1000.0 %] Enter the maximum permissible current

when using AC brake to avoid overheating of motor windings.

NOTICE

Parameter 2-16 AC brake Max. Current has no effect when 1-10 Motor Construction[1] PM, non salient SPM.

2-17 Over-voltage Control

Option: Function:

Overvoltage control (OVC) reduces the risk of the frequency converter tripping due to an overvoltage on the DC-link caused by generative power from the load.

[0] * Disabled No OVC required.

[1] Enabled (not

at stop)

[2] Enabled Activates OVC.

Activates OVC except when using a stop signal to stop the frequency converter.

NOTICE

Do not enable OVC in hoisting applications.

2-18 Brake Check Condition

Range: Function:

[0] * At Power Up Brake check is performed at power

up.

[1] After Coast Situations Brake check is performed after coast

situations.

16-32 Brake Energy /s

Range: Function:

0 kW* [0 - 10000 kW] View the brake power transmitted to an

external brake resistor, stated as an instantaneous value.

5 5

Programming Design Guide

16-33 Brake Energy /2 min

Range: Function:

0 kW* [0 - 10000

kW]

View the brake power transmitted to an external brake resistor. The mean power is calculated on an average level based on the selected time period within 2-13 Brake Power Monitoring.

30-81 Brake Resistor (ohm)

Range: Function:

Size

55

related*

[ 0.01 -

65535.00 Ohm]

Set the brake resistor value in Ω. This value is used for monitoring the power to the brake resistor in 2-13 Brake Power Monitoring. This parameter is only active in frequency converters with an integral dynamic brake.

5.4

Parameters for VLT® AutomationDrive FC 360

2-10 Brake Function

Option: Function:

[0]*Off No brake resistor is installed.

[1] Resistor

brake

[2] AC brake Improves braking without using a brake resistor.

A brake resistor is incorporated in the system for dissipation of surplus brake energy as heat. Connecting a brake resistor allows a higher DClink voltage during braking (generating operation). The brake resistor function is only active in frequency converters with an integral dynamic brake.

This parameter controls an overmagnetisation of the motor when running with a generatoric load. This function can improve the OVC-function. Increasing the electrical losses in the motor allows the OVC-function to increase braking torque without exceeding the voltage limit.

NOTICE

The AC brake is not as efficient as dynamic braking with resistor. AC brake is for VVC+ mode in both open and closed loop.

2-11 Brake Resistor (ohm)

Range: Function:

Size related*

[ 0 65535 Ohm]

Set the brake resistor value in Ω. This value is used for monitoring the power to the brake resistor. Parameter 2-11 Brake Resistor (ohm) is only active in frequency converters with an integral dynamic brake. Use this parameter for values without decimals.

2-12 Brake Power Limit (kW)

Range: Function:

Size related*

[0.001

- 2000 kW]

Parameter 2-12 Brake Power Limit (kW) is the expected average power dissipated in the brake resistor over a period of 120 s. It is used as the monitoring limit for 16-33 Brake Energy /2 min and thereby specifies when a warning/alarm is to be given. To calculate parameter 2-12 Brake Power Limit (kW), the following formula can be used.

P

W

=

br,avg

P

is the average power dissipated in the

br,avg

brake resistor, Rbr is the resistance of the

2

U

V×tbrs

br

RbrΩ×Tbrs

Programming Design Guide

2-12 Brake Power Limit (kW)

Range: Function:

brake resistor. tbr is the active breaking time within the 120 s period, Tbr. Ubr is the DC voltage where the brake resistor is active. This depends on the unit as follows: T4 units: 778 V

NOTICE

If Rbr is not known or if Tbr is different from 120 s, the practical approach is to run the brake application, readout 16-33 Brake Energy /2 min and then enter this + 20% in 2-12 Brake Power Limit (kW).

2-16 AC Brake, Max current

Range: Function:

100 %* [0 - 160%]Enter the maximum permissible current

when using AC brake to avoid overheating of motor windings.

NOTICE

Parameter 2-16 AC Brake, Max current has no effect when 1-10 Motor Construction is set to [1] PM, nonsalient SPM.

2-17 Over-voltage Control

Option: Function:

Overvoltage control (OVC) reduces the risk of the frequency converter tripping due to an overvoltage on the DC-link caused by generative power from the load.

[0] * Disabled No OVC required.

[1] Enabled

(not at stop)

[2] Enabled Activates OVC

Activates OVC except when using a stop signal to stop the frequency converter.

WARNING

Do NOT enable OVC in hoisting applications.

5.5

Parameters for VLT® 2800

126 DC brake time

Range: Function:

10 sec* [0 - 60 sec.] The DC brake time is set at which

parameter 132 DC brake voltage is to be active.

127 DC brake cut-in frequency

Range: Function:

0.00 OFF* [0.0 (OFF) par. 202]

Set the DC brake cut-in frequency at which the DC brake is to be activated in connection with a stop command.

132 DC brake voltage

Range: Function:

0%* [0 - 100% of

max. DC brake voltage]

Set the DC brake voltage to be activated at stop when the DC brake frequency set in parameter 127 DC brake cut-in frequency is reached, or if DC braking inverse is active via a digital input or via serial communication. Subsequently, the DC brake voltage is active for the time set in parameter 126 DC brake time.

400 Brake function

Option: Function:

[0] Off [1] Resistor

brake

[4] AC brake

[5] Load

sharing

Select [1] Resistor brake if the frequency converter has an integral brake transistor, and a brake resistor is connected to terminals 81, 82. A higher DC-link voltage is permitted during braking (generated operation) when a brake resistor is connected. Select [4] AC brake to improve braking without using brake resistors. Note that [4] AC brake is not as effective as [1] Resistor brake.

NOTICE

Disconnected and reconnect mains voltage to activate a change of selection.

5 5

Programming Design Guide

456 Brake Voltage Reduce

Range: Function:

0*0* [0-25 V if 200 V

device] [0-50 V if 400 V device]

Set the voltage by which the level for resistor braking is reduced. It is only active when [1] Resistor is selected in parameter 400 Brake function.

NOTICE

The greater the reduction value, the faster the reaction to a generator overload. Should only be used if there are problems with overvoltage in the DC-link voltage.

55

Application Examples Design Guide

6 Application Examples

6.1 Conveyor Belt

Illustration 6.1 shows the relation between the braking power and the acceleration/braking of a conveyor belt. Note:

The motor power during braking is negative,

•

since the torque on the motor shaft is negative. The motor power is time-dependent.

•

The braking power (the power to be dissipated to the brake resistor) corresponds almost exactly to the negative motor power plus losses in the motor and the frequency converter.

Kinetic energy (E) in conveyor belt + motor:

E

= 0. 5 × m ×

where

m = mass with linear movement [kg] v = speed of mass with linear movement [m/s]

j = inertia of motor and gear box [kgm2] ω = motor speed [rad/s]

2

v

+ 0 .5 × j × ω

2

Ws

Insert:

n

× 2π

ω

=

60

The result is:

E

= 0 .5×

b

2

m v

+ 0 .0055 ×

2

j

×

n

− 0 .052 × n ×

M

×

η

Ws

f

M

6 6

n

ω

= motor speed =

× 2π

60

rad /

s

This formula is also expressed as follows:

E

= 0. 50 × m ×

2

v

+ 0 .0055 × j ×

n2Ws

However, not all of the energy is dissipated in the brake resistor. The friction of the conveyor belt and the power loss of the motor also contribute to the braking function. So, the formula for energy dissipation (Eb) to the brake resistor is as follows:

E

= 0 .5×

b

m v

2

+ 0 .5

jω

2

− 0 .5 ×

Mfω

×

η

M

Ws

where

Mf = Friction torque [Nm]

ŋM = Motor efficiency

P

average

Time [s]

Length [m]

175ZA397.14

Acceleration

Braking

P

braking, avg.

P

[W]

Motor power

P

[W]

Brake power

M

[Nm]

Torque

V

[m/s]

Speed

VLT®

M

V

[m/s]

Speed

m v

T

p

m

ϖ

[m/s]

T

p

Application Examples

Design Guide

66

Illustration 6.1 Conveyor Belt: Relation between Braking Power and Acceleration/Deceleration

Danfoss VLT Brake Resistor MCE 101 Design Manual

Specifications and Main Features

Frequently Asked Questions

User Manual