ENGINEERING TOMORROW
Design Guide
VLT® HVAC Basic Drive FC 101
vlt-drives.danfoss.com
Contents |
Design Guide |
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Contents
1 Introduction |
6 |
1.1 Purpose of the Design Guide |
6 |
1.2 Document and Software Version |
6 |
1.3 Safety Symbols |
6 |
1.4 Abbreviations |
7 |
1.5 Additional Resources |
7 |
1.6 De€nitions |
7 |
1.7 Power Factor |
9 |
1.8 Regulatory Compliance |
10 |
1.8.1 CE Mark |
10 |
1.8.2 UL Compliance |
10 |
1.8.3 RCM Mark Compliance |
10 |
1.8.4 EAC |
11 |
1.8.5 UkrSEPRO |
11 |
2 Safety |
12 |
2.1 Quali€ed Personnel |
12 |
2.2 Safety Precautions |
12 |
3 Product Overview |
14 |
3.1 Advantages |
14 |
3.1.1 Why use a Frequency Converter for Controlling Fans and Pumps? |
14 |
3.1.2 The Clear Advantage - Energy Savings |
14 |
3.1.3 Example of Energy Savings |
14 |
3.1.4 Comparison of Energy Savings |
15 |
3.1.5 Example with Varying Flow over 1 Year |
16 |
3.1.6 Better Control |
16 |
3.1.7 Star/Delta Starter or Soft Starter not Required |
17 |
3.1.8 Using a Frequency Converter Saves Money |
17 |
3.1.9 Without a Frequency Converter |
18 |
3.1.10 With a Frequency Converter |
19 |
3.1.11 Application Examples |
19 |
3.1.12 Variable Air Volume |
19 |
3.1.13 The VLT Solution |
20 |
3.1.14 Constant Air Volume |
21 |
3.1.15 The VLT Solution |
21 |
3.1.16 Cooling Tower Fan |
22 |
3.1.17 The VLT Solution |
22 |
3.1.18 Condenser Pumps |
23 |
3.1.19 The VLT Solution |
23 |
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
1 |
Contents |
VLT® HVAC Basic Drive FC 101 |
3.1.20 Primary Pumps |
24 |
3.1.21 The VLT Solution |
24 |
3.1.22 Secondary Pumps |
26 |
3.1.23 The VLT Solution |
26 |
3.2 Control Structures |
27 |
3.2.1 Control Structure Open Loop |
27 |
3.2.2 PM/EC+ Motor Control |
27 |
3.2.3 Local (Hand On) and Remote (Auto On) Control |
27 |
3.2.4 Control Structure Closed Loop |
28 |
3.2.5 Feedback Conversion |
28 |
3.2.6 Reference Handling |
29 |
3.2.7 Tuning the Drive Closed-loop Controller |
30 |
3.2.8 Manual PI Adjustment |
30 |
3.3 Ambient Running Conditions |
30 |
3.4 General Aspects of EMC |
36 |
3.4.1 Overview of EMC Emissions |
36 |
3.4.2 Emission Requirements |
38 |
3.4.3 EMC Emission Test Results |
39 |
3.4.4 Overview of Harmonics Emission |
41 |
3.4.5 Harmonics Emission Requirements |
41 |
3.4.6 Harmonics Test Results (Emission) |
41 |
3.4.7 Immunity Requirements |
43 |
3.5 Galvanic Isolation (PELV) |
43 |
3.6 Earth Leakage Current |
44 |
3.7 Extreme Running Conditions |
44 |
3.7.1 Motor Thermal Protection (ETR) |
44 |
3.7.2 Thermistor Inputs |
45 |
4 Selection and Ordering |
47 |
4.1 Type Code |
47 |
4.2 Options and Accessories |
48 |
4.2.1 Local Control Panel (LCP) |
48 |
4.2.2 Mounting of LCP in Panel Front |
48 |
4.2.3 IP21/NEMA Type 1 Enclosure Kit |
49 |
4.2.4 Decoupling Plate |
51 |
4.3 Ordering Numbers |
51 |
4.3.1 Options and Accessories |
51 |
4.3.2 Harmonic Filters |
52 |
4.3.3 External RFI Filter |
54 |
5 Installation |
55 |
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Danfoss A/S © 04/2018 All rights reserved. |
MG18C802 |
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Design Guide |
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5.1 Electrical Installation |
55 |
5.1.1 Mains and Motor Connection |
57 |
5.1.2 EMC-compliant Electrical Installation |
62 |
5.1.3 Control Terminals |
64 |
6 Programming |
65 |
6.1 Introduction |
65 |
6.2 Local Control Panel (LCP) |
65 |
6.3 Menus |
66 |
6.3.1 Status Menu |
66 |
6.3.2 Quick Menu |
66 |
6.3.3 Main Menu |
80 |
6.4 Quick Transfer of Parameter Settings between Multiple Frequency Converters |
80 |
6.5 Readout and Programming of Indexed Parameters |
81 |
6.6 Initialization to Default Settings |
81 |
7 RS485 Installation and Set-up |
82 |
7.1 RS485 |
82 |
7.1.1 Overview |
82 |
7.1.2 Network Connection |
82 |
7.1.3 Frequency Converter Hardware Set-up |
82 |
7.1.4 Parameter Settings for Modbus Communication |
83 |
7.1.5 EMC Precautions |
83 |
7.2 FC Protocol |
84 |
7.2.1 Overview |
84 |
7.2.2 FC with Modbus RTU |
84 |
7.3 Parameter Settings to Enable the Protocol |
84 |
7.4 FC Protocol Message Framing Structure |
84 |
7.4.1 Content of a Character (Byte) |
84 |
7.4.2 Telegram Structure |
84 |
7.4.3 Telegram Length (LGE) |
85 |
7.4.4 Frequency Converter Address (ADR) |
85 |
7.4.5 Data Control Byte (BCC) |
85 |
7.4.6 The Data Field |
85 |
7.4.7 The PKE Field |
85 |
7.4.8 Parameter Number (PNU) |
86 |
7.4.9 Index (IND) |
86 |
7.4.10 Parameter Value (PWE) |
86 |
7.4.11 Data Types Supported by the Frequency Converter |
87 |
7.4.12 Conversion |
87 |
7.4.13 Process Words (PCD) |
87 |
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
3 |
Contents |
VLT® HVAC Basic Drive FC 101 |
7.5 Examples |
87 |
7.5.1 Writing a Parameter Value |
87 |
7.5.2 Reading a Parameter Value |
88 |
7.6 Modbus RTU Overview |
88 |
7.6.1 Introduction |
88 |
7.6.2 Overview |
88 |
7.6.3 Frequency Converter with Modbus RTU |
89 |
7.7 Network Con€guration |
89 |
7.8 Modbus RTU Message Framing Structure |
89 |
7.8.1 Introduction |
89 |
7.8.2 Modbus RTU Telegram Structure |
89 |
7.8.3 Start/Stop Field |
90 |
7.8.4 Address Field |
90 |
7.8.5 Function Field |
90 |
7.8.6 Data Field |
90 |
7.8.7 CRC Check Field |
90 |
7.8.8 Coil Register Addressing |
90 |
7.8.9 Access via PCD write/read |
92 |
7.8.10 How to Control the Frequency Converter |
93 |
7.8.11 Function Codes Supported by Modbus RTU |
93 |
7.8.12 Modbus Exception Codes |
93 |
7.9 How to Access Parameters |
94 |
7.9.1 Parameter Handling |
94 |
7.9.2 Storage of Data |
94 |
7.9.3 IND (Index) |
94 |
7.9.4 Text Blocks |
94 |
7.9.5 Conversion Factor |
94 |
7.9.6 Parameter Values |
94 |
7.10 Examples |
94 |
7.10.1 Read Coil Status (01 hex) |
94 |
7.10.2 Force/Write Single Coil (05 hex) |
95 |
7.10.3 Force/Write Multiple Coils (0F hex) |
95 |
7.10.4 Read Holding Registers (03 hex) |
96 |
7.10.5 Preset Single Register (06 hex) |
96 |
7.10.6 Preset Multiple Registers (10 hex) |
97 |
7.10.7 Read/Write Multiple Registers (17 hex) |
97 |
7.11 Danfoss FC Control Pro€le |
98 |
7.11.1 Control Word According to FC Pro€le (8-10 Protocol = FC Pro€le) |
98 |
7.11.2 Status Word According to FC Pro€le (STW) |
99 |
7.11.3 Bus Speed Reference Value |
101 |
4 |
Danfoss A/S © 04/2018 All rights reserved. |
MG18C802 |
Contents |
Design Guide |
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8 General Speci€cations |
102 |
8.1 Mechanical Dimensions |
102 |
8.1.1 Side-by-side Installation |
102 |
8.1.2 Frequency Converter Dimensions |
103 |
8.1.3 Shipping Dimensions |
105 |
8.1.4 Field Mounting |
106 |
8.2 Mains Supply Speci€cations |
107 |
8.2.1 3x200–240 V AC |
107 |
8.2.2 3x380–480 V AC |
108 |
8.2.3 3x525–600 V AC |
112 |
8.3 Fuses and Circuit Breakers |
113 |
8.4 General Technical Data |
115 |
8.4.1 Mains Supply (L1, L2, L3) |
115 |
8.4.2 Motor Output (U, V, W) |
115 |
8.4.3 Cable Length and Cross-section |
116 |
8.4.4 Digital Inputs |
116 |
8.4.5 Analog Inputs |
116 |
8.4.6 Analog Output |
116 |
8.4.7 Digital Output |
117 |
8.4.8 Control Card, RS485 Serial Communication |
117 |
8.4.9 Control Card, 24 V DC Output |
117 |
8.4.10 Relay Output |
117 |
8.4.11 Control Card, 10 V DC Output |
118 |
8.4.12 Ambient Conditions |
118 |
8.5 dU/Dt |
119 |
Index |
122 |
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
5 |
Introduction VLT® HVAC Basic Drive FC 101
1 |
1 |
1 Introduction |
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1.1 Purpose of the Design Guide
This design guide is intended for project and systems engineers, design consultants, and application and product specialists. Technical information is provided to understand the capabilities of the frequency converter for integration into motor control and monitoring systems. Details concerning operation, requirements, and recommendations for system integration are described. Information is proved for input power characteristics, output for motor control, and ambient operating conditions for the frequency converter.
Also included are:
•Safety features.
•Fault condition monitoring.
•Operational status reporting.
•Serial communication capabilities.
•Programmable options and features.
Also provided are design details such as:
•Site requirements.
•Cables.
•Fuses.
•Control wiring.
•Unit sizes and weights.
•Other critical information necessary to plan for system integration.
Reviewing the detailed product information in the design stage enables developing a well-conceived system with optimal functionality and efficiency.
VLT® is a registered trademark.
1.2 Document and Software Version
This manual is regularly reviewed and updated. All suggestions for improvement are welcome.
with regards to backwards compatibility for H1–H5 and I2– I4 enclosure sizes. Refer to Table 1.2 for the limitations.
Software |
Old control card |
New control card |
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compatibility |
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33 2017 or before) |
34 2017 or after) |
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Old software |
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(OSS-€le version 3.xx |
Yes |
No |
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and below) |
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New software |
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(OSS-€le version 4.xx |
No |
Yes |
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or higher) |
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Hardware |
Old control card |
New control card |
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(production week |
(production week |
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compatibility |
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33 2017 or before) |
34 2017 or after) |
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Old power card |
Yes (only software |
Yes (MUST update |
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(production week 33 |
version 3.xx or |
software to version |
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2017 or before) |
below) |
4.xx or higher) |
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Yes (MUST update |
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New power card |
software to version |
Yes (only software |
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(production week 34 |
3.xx or below, the |
version 4.xx or |
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2017 or after) |
fan continuously |
higher) |
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runs at full speed) |
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Table 1.2 Software and Hardware Compatibility
1.3 Safety Symbols
The following symbols are used in this guide:
WARNING
Indicates a potentially hazardous situation that could result in death or serious injury.
CAUTION
Indicates a potentially hazardous situation that could result in minor or moderate injury. It can also be used to alert against unsafe practices.
Edition |
Remarks |
Software version |
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MG18C8xx |
Update to new SW & HW version. |
4.2x |
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Table 1.1 Document and Software Version
From software version 4.0x and later (production week 33 2017 and after), the variable speed heat sink cooling fan function is implemented in the frequency converter for power sizes 22 kW (30 hp) 400 V IP20 and below, and 18.5 kW (25 hp) 400 V IP54 and below. This function requires software and hardware updates and introduces restrictions
NOTICE
Indicates important information, including situations that can result in damage to equipment or property.
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MG18C802 |
Introduction |
Design Guide |
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1.4 |
Abbreviations |
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VLT® Energy Box software allows energy |
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consumption comparisons of HVAC fans and |
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°C |
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Degrees Celsius |
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pumps driven by Danfoss frequency converters |
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°F |
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Degrees Fahrenheit |
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and alternative methods of flow control. Use this |
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A |
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Ampere/AMP |
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tool to accurately project the costs, savings, and |
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payback of using Danfoss frequency converters |
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AC |
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Alternating current |
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on HVAC fans, pumps, and cooling towers. |
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AMA |
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Automatic motor adaptation |
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AWG |
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American wire gauge |
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Danfoss technical literature is available in electronic form |
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DC |
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Direct current |
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on the documentation CD that is shipped with the |
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EMC |
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Electro magnetic compatibility |
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product, or in print from your local Danfoss sales office. |
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ETR |
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Electronic thermal relay |
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FC |
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Frequency converter |
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MCT 10 Set-up Software support |
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fM,N |
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Nominal motor frequency |
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Download the software from www.danfoss.com/en/service- |
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kg |
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Kilogram |
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and-support/downloads/dds/vlt-motion-control-tool-mct-10/. |
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Hz |
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Hertz |
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During the installation process of the software, enter |
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IINV |
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Rated inverter output current |
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access code 81463800 to activate the FC 101 functionality. |
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ILIM |
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Current limit |
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A license key is not required for using the FC 101 |
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IM,N |
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Nominal motor current |
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functionality. |
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IVLT,MAX |
The maximum output current |
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The latest software does not always contain the latest |
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IVLT,N |
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The rated output current supplied by the |
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updates for frequency converters. Contact the local sales |
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frequency converter |
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office for the latest frequency converter updates (in the |
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kHz |
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Kilohertz |
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form of *.upd €les), or download the frequency converter |
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LCP |
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Local control panel |
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updates from www.danfoss.com/en/service-and-support/ |
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m |
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Meter |
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downloads/dds/vlt-motion-control-tool-mct-10/#Overview. |
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mA |
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Milliampere |
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1.6 De€nitions |
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MCT |
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Motion control tool |
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mH |
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Millihenry inductance |
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Frequency converter |
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min |
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Minute |
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IVLT, MAX |
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ms |
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Millisecond |
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The maximum output current. |
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nF |
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Nanofarad |
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IVLT,N |
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Nm |
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Newton meters |
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The rated output current supplied by the frequency |
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ns |
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Synchronous motor speed |
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converter. |
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PM,N |
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Nominal motor power |
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UVLT, MAX |
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PCB |
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Printed circuit board |
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The maximum output voltage. |
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PELV |
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Protective extra low voltage |
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Input |
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Regen |
Regenerative terminals |
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The connected motor can start and stop via LCP and |
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RPM |
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Revolutions per minute |
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digital inputs. Functions are divided into 2 groups, as |
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Second |
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described in Table 1.4. Functions in group 1 have higher |
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TLIM |
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Torque limit |
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priority than functions in group 2. |
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UM,N |
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Nominal motor voltage |
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V |
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Volts |
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Group 1 |
Reset, coast stop, reset and coast stop, quick |
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Table 1.3 Abbreviations |
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stop, DC brake, stop, and [Off]. |
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Group 2 |
Start, pulse start, reversing, start reversing, jog, |
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1.5 |
Additional Resources |
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and freeze output. |
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Table 1.4 Control Commands |
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• |
VLT® HVAC Basic Drive FC 101 Quick Guide provides |
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basic information on mechanical dimensions, |
Motor |
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installation, and programming. |
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fJOG |
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•VLT® HVAC Basic Drive FC 101 Programming Guide The motor frequency when the jog function is activated
provides information on how to program, and includes complete parameter descriptions.
•Danfoss VLT® Energy Box software. Select PC Software Download at www.danfoss.com/en/ service-and-support/downloads/dds/vlt-energy-box/.
(via digital terminals).
fM
The motor frequency.
fMAX
The maximum motor frequency.
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
7 |
Introduction |
VLT® HVAC Basic Drive FC 101 |
1 1 fMIN
The minimum motor frequency.
fM,N
The rated motor frequency (nameplate data).
IM
The motor current.
IM,N
The rated motor current (nameplate data).
nM,N
The nominal motor speed (nameplate data).
PM,N
The rated motor power (nameplate data).
UM
The instantaneous motor voltage.
UM,N
The rated motor voltage (nameplate data).
Break-away torque
Torque |
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Pull-out |
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RPM
Illustration 1.1 Break-away Torque
ηVLT
The efficiency of the frequency converter is de€ned as the ratio between the power output and the power input.
Start-disable command
A stop command belonging to the group 1 control commands, see Table 1.4.
Stop command
See Table 1.4.
Analog reference
A signal transmitted to the analog inputs 53 or 54. It can be voltage or current.
•Current input: 0–20 mA and 4–20 mA
•Voltage input: 0–10 V DC
Bus reference
A signal transmitted to the serial communication port (FC port).
Preset reference
A de€ned preset reference to be set from -100% to +100% of the reference range. Selection of 8 preset references via the digital terminals.
RefMAX
Determines the relationship between the reference input at 100% full scale value (typically 10 V, 20 mA) and the resulting reference. The maximum reference value set in parameter 3-03 Maximum Reference.
RefMIN
Determines the relationship between the reference input at 0% value (typically 0 V, 0 mA, 4 mA) and the resulting reference. The minimum reference value is set in
parameter 3-02 Minimum Reference.
Analog inputs
The analog inputs are used for controlling various functions of the frequency converter.
There are 2 types of analog inputs:
•Current input: 0–20 mA and 4–20 mA
•Voltage input: 0–10 V DC
Analog outputs
The analog outputs can supply a signal of 0–20 mA, 4– 20 mA, or a digital signal.
Automatic motor adaptation, AMA
The AMA algorithm determines the electrical parameters for the connected motor at standstill and compensates for the resistance based on the length of the motor cable.
Digital inputs
The digital inputs can be used for controlling various functions of the frequency converter.
Digital outputs
The frequency converter provides 2 solid-state outputs that can supply a 24 V DC (maximum 40 mA) signal.
Relay outputs
The frequency converter provides 2 programmable relay outputs.
ETR
Electronic thermal relay is a thermal load calculation based on present load and time. Its purpose is to estimate the motor temperature and prevent overheating of the motor.
Initializing
If initializing is carried out (parameter 14-22 Operation Mode), the programmable parameters of the frequency converter return to their default settings.
Parameter 14-22 Operation Mode does not initialize communication parameters, fault log, or €re mode log.
Intermittent duty cycle
An intermittent duty rating refers to a sequence of duty cycles. Each cycle consists of an on-load and an off-load period. The operation can be either periodic duty or noneperiodic duty.
8 |
Danfoss A/S © 04/2018 All rights reserved. |
MG18C802 |
Introduction |
Design Guide |
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LCP
The local control panel (LCP) makes up a complete interface for control and programming of the frequency converter. The control panel is detachable on IP20 units and €xed on IP54 units. It can be installed up to 3 m (9.8 ft) from the frequency converter, that is, in a front panel with the installation kit option.
Lsb
Least signi€cant bit.
MCM
Short for mille circular mil, an American measuring unit for cable cross-section. 1 MCM = 0.5067 mm2.
Msb
Most signi€cant bit.
On-line/Oƒ-line parameters
Changes to on-line parameters are activated immediately after the data value is changed. Press [OK] to activate offline parameters.
PI controller
The PI controller maintains the desired speed, pressure, temperature, and so on, by adjusting the output frequency to match the varying load.
RCD
Residual current device.
Set-up
Parameter settings in 2 set-ups can be saved. Change between the 2 parameter set-ups and edit 1 set-up, while another set-up is active.
Slip compensation
The frequency converter compensates for the motor slip by giving the frequency a supplement that follows the measured motor load keeping the motor speed almost constant.
Smart logic control (SLC)
The SLC is a sequence of user-de€ned actions executed when the associated user-de€ned events are evaluated as true by the SLC.
Thermistor
A temperature-dependent resistor placed where the temperature is to be monitored (frequency converter or motor).
Trip |
1 1 |
A state entered in fault situations, for example, if the frequency converter is subject to an overtemperature or when the frequency converter is protecting the motor, process, or mechanism. Restart is prevented until the cause of the fault does not exist and the trip state is canceled by activating reset or, sometimes, by being programmed to reset automatically. Do not use trip for personal safety.
Trip lock
A state entered in fault situations when the frequency converter is protecting itself and requiring physical intervention, for example, if the frequency converter is subject to a short circuit on the output. A locked trip can only be canceled by cutting off mains, removing the cause of the fault, and reconnecting the frequency converter. Restart is prevented until the trip state is canceled by activating reset or, sometimes, by being programmed to reset automatically. Do not use trip lock for personal safety.
VT characteristics
Variable torque characteristics used for pumps and fans.
VVC+
If compared with standard voltage/frequency ratio control, voltage vector control (VVC+) improves the dynamics and the stability, both when the speed reference is changed and in relation to the load torque.
1.7 Power Factor
The power factor indicates to which extent the frequency converter imposes a load on the mains supply. The power factor is the ratio between I1 and IRMS, where I1 is the fundamental current, and IRMS is the total RMS current including harmonic currents. The lower the power factor, the higher the IRMS for the same kW performance.
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currents are low.
The frequency converters built-in DC coils produce a highpower factor, which minimizes the imposed load on the mains supply.
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
9 |
Introduction |
VLT® HVAC Basic Drive FC 101 |
1 1 1.8 Regulatory Compliance
Frequency converters are designed in compliance with the directives described in this section.
1.8.1 CE Mark
The CE mark (Communauté Européenne) indicates that the product manufacturer conforms to all applicable EU directives. The EU directives applicable to the design and manufacture of frequency converters are listed in Table 1.5.
NOTICE
The CE mark does not regulate the quality of the product. Technical speci€cations cannot be deduced from the CE mark.
CE mark, but must comply with the basic protection requirements of the EMC directive.
1.8.1.3 ErP Directive
The ErP directive is the European Ecodesign Directive for energy-related products. The directive sets ecodesign requirements for energy-related products, including frequency converters. The directive aims at increasing energy efficiency and the level of protection of the environment, while increasing the security of the energy supply. Environmental impact of energy-related products includes energy consumption throughout the entire product life cycle.
1.8.2 UL Compliance
UL-listed
NOTICE
Frequency converters with an integrated safety function must comply with the machinery directive.
EU directive |
Version |
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Low Voltage Directive |
2014/35/EU |
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EMC Directive |
2014/30/EU |
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Table 1.5 EU Directives Applicable to Frequency Converters
Declarations of conformity are available on request.
1.8.1.1 Low Voltage Directive
The low voltage directive applies to all electrical equipment in the 50–1000 V AC and the 75–1600 V DC voltage ranges.
The aim of the directive is to ensure personal safety and avoid property damage, when operating electrical equipment that is installed and maintained correctly in its intended application.
1.8.1.2 EMC Directive
The purpose of the EMC (electromagnetic compatibility) directive is to reduce electromagnetic interference and enhance immunity of electrical equipment and installations. The basic protection requirement of the EMC Directive 2014/30/EU states that devices that generate electromagnetic interference (EMI), or whose operation could be affected by EMI, must be designed to limit the generation of electromagnetic interference and shall have a suitable degree of immunity to EMI when properly installed, maintained, and used as intended.
Electrical equipment devices used alone or as part of a system must bear the CE mark. Systems do not require the
Illustration 1.2 UL
NOTICE
IP54 units are not certi€ed for UL.
The frequency converter complies with UL 508C thermal memory retention requirements. For more information, refer to the section Motor Thermal Protection in the product-speci€c design guide.
1.8.3 RCM Mark Compliance
Illustration 1.3 RCM Mark
The RCM Mark label indicates compliance with the applicable technical standards for Electromagnetic Compatibility (EMC). An RCM Mark label is required for placing electrical and electronic devices on the market in Australia and New Zealand. The RCM Mark regulatory arrangements only deal with conducted and radiated emission. For frequency converters, the emission limits speci€ed in EN/IEC 61800-3 apply. A declaration of conformity can be provided on request.
10 |
Danfoss A/S © 04/2018 All rights reserved. |
MG18C802 |
Introduction |
Design Guide |
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1.8.4 EAC |
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Illustration 1.4 EAC Mark
The EurAsian Conformity (EAC) mark indicates that the product conforms to all requirements and technical regulations applicable to the product per the EurAsian Customs Union, which is composed of the member states of the EurAsian Economic Union.
The EAC logo must be both on the product label and on the packaging label. All products used within the EAC area, must be bought at Danfoss inside the EAC area.
1.8.5 UkrSEPRO
089
Illustration 1.5 UkrSEPRO
UKrSEPRO certi€cate ensures quality and safety of both products and services, in addition to manufacturing stability according to Ukrainian regulatory standards. The UkrSepro certi€cate is a required document to clear customs for any products coming into and out of the territory of Ukraine.
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
11 |
Safety |
VLT® HVAC Basic Drive FC 101 |
2 Safety
2 2
2.1 Quali€ed Personnel
Correct and reliable transport, storage, installation, operation, and maintenance are required for the troublefree and safe operation of the frequency converter. Only quali€ed personnel are allowed to install or operate this equipment.
Quali€ed personnel are de€ned as trained staff, who are authorized to install, commission, and maintain equipment, systems, and circuits in accordance with pertinent laws and regulations. Also, the personnel must be familiar with the instructions and safety measures described in this guide.
2.2 Safety Precautions
WARNING
HIGH VOLTAGE
Frequency converters contain high voltage when connected to AC mains input, DC supply, or load sharing. Failure to perform installation, start-up, and maintenance by quali€ed personnel can result in death or serious injury.
•Only quali€ed personnel must perform installation, start-up, and maintenance.
•Before performing any service or repair work, use an appropriate voltage measuring device to make sure that there is no remaining voltage on the frequency converter.
WARNING
UNINTENDED START
When the drive is connected to AC mains, DC supply, or load sharing, the motor can start at any time. Unintended start during programming, service, or repair work can result in death, serious injury, or property damage. The motor can start with an external switch, a €eldbus command, an input reference signal from the LCP or LOP, via remote operation using MCT 10 Set-up Software, or after a cleared fault condition.
To prevent unintended motor start:
•Press [Oƒ/Reset] on the LCP before programming parameters.
•Disconnect the drive from the mains.
•Completely wire and assemble the drive, motor, and any driven equipment before connecting the drive to AC mains, DC supply, or load sharing.
WARNING
DISCHARGE TIME
The frequency converter contains DC-link capacitors, which can remain charged even when the frequency converter is not powered. High voltage can be present even when the warning LED indicator lights are oƒ. Failure to wait the speci€ed time after power has been removed before performing service or repair work can result in death or serious injury.
•Stop the motor.
•Disconnect AC mains and remote DC-link power supplies, including battery back-ups, UPS, and DC-link connections to other frequency converters.
•Disconnect or lock PM motor.
•Wait for the capacitors to discharge fully. The minimum duration of waiting time is speci€ed in Table 2.1.
•Before performing any service or repair work, use an appropriate voltage measuring device to make sure that the capacitors are fully discharged.
Voltage [V] |
Power range [kW (hp)] |
Minimum waiting time |
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0.37–7.5 (0.5–10) |
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11–90 (15–125) |
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Table 2.1 Discharge Time
WARNING
LEAKAGE CURRENT HAZARD
Leakage currents exceed 3.5 mA. Failure to ground the frequency converter properly can result in death or serious injury.
•Ensure the correct grounding of the equipment by a certi€ed electrical installer.
12 |
Danfoss A/S © 04/2018 All rights reserved. |
MG18C802 |
Safety Design Guide
WARNING
EQUIPMENT HAZARD |
2 2 |
Contact with rotating shafts and electrical equipment |
can result in death or serious injury.
•Ensure that only trained and quali€ed personnel perform installation, start-up, and maintenance.
•Ensure that electrical work conforms to national and local electrical codes.
•Follow the procedures in this manual.
CAUTION
INTERNAL FAILURE HAZARD
An internal failure in the frequency converter can result in serious injury when the frequency converter is not properly closed.
•Ensure that all safety covers are in place and securely fastened before applying power.
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
13 |
Product Overview |
VLT® HVAC Basic Drive FC 101 |
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3 Product Overview |
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3.1 Advantages |
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A frequency converter takes advantage of the fact that |
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technologies, a frequency converter is the optimum energy |
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control system for controlling fan and pump systems. |
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Illustration 3.1 Fan Curves (A, B, and C) for Reduced Fan
Volumes
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Illustration 3.2 Energy Savings with Frequency Converter Solution
When using a frequency converter to reduce fan capacity to 60% - more than 50% energy savings may be obtained in typical applications.
3.1.3 Example of Energy Savings
As shown in Illustration 3.3, the flow is controlled by changing the RPM. By reducing the speed by only 20% from the rated speed, the flow is also reduced by 20%. This is because the flow is directly proportional to the RPM. The consumption of electricity, however, is reduced by 50%.
If the system in question only needs to be able to supply a flow that corresponds to 100% a few days in a year, while the average is below 80% of the rated flow for the remainder of the year, the amount of energy saved is even more than 50%.
14 |
Danfoss A/S © 04/2018 All rights reserved. |
MG18C802 |
Product Overview |
Design Guide |
Illustration 3.3 describes the dependence of flow, pressure, and power consumption on RPM.
100% |
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<![if ! IE]> <![endif]>175HA208.10 |
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Table 3.1 The Laws of Proportionality
3.1.4 Comparison of Energy Savings
The Danfoss frequency converter solution offers major savings compared with traditional energy saving solutions such as discharge damper solution and inlet guide vanes (IGV) solution. This is because the frequency converter is able to control fan speed according to thermal load on the system, and the frequency converter has a built-in facility that enables the frequency converter to function as a building management system, BMS.
Illustration 3.3 shows typical energy savings obtainable with 3 well-known solutions when fan volume is reduced to 60%.
As the graph shows, more than 50% energy savings can be achieved in typical applications.
<![endif]>130BA782.10
Discharge |
3 |
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damper |
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Maximum energy savings
IGV
Costlier installation
Illustration 3.4 The 3 Common Energy Saving Systems
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Illustration 3.5 Energy Savings
Discharge dampers reduce power consumption. Inlet guide vanes offer a 40% reduction, but are expensive to install. The Danfoss frequency converter solution reduces energy consumption with more than 50% and is easy to install. It also reduces noise, mechanical stress, and wear-and-tear, and extends the life span of the entire application.
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
15 |
Product Overview |
VLT® HVAC Basic Drive FC 101 |
3.1.5Example with Varying Flow over 1 Year
This example is calculated based on pump characteristics obtained from a pump datasheet.
3 3 The result obtained shows energy savings of more than 50% at the given flow distribution over a year. The payback period depends on the price per kWh and the price of frequency converter. In this example, it is less than a year when compared with valves and constant speed.
Energy savings
Pshaft = Pshaft output
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[m3 /h] |
Illustration 3.6 Flow Distribution over 1 Year
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Table 3.2 Result
3.1.6 Better Control
If a frequency converter is used for controlling the flow or pressure of a system, improved control is obtained.
A frequency converter can vary the speed of the fan or pump, obtaining variable control of flow and pressure. Furthermore, a frequency converter can quickly adapt the speed of the fan or pump to new flow or pressure conditions in the system.
Simple control of process (flow, level, or pressure) utilizing the built-in PI control.
16 |
Danfoss A/S © 04/2018 All rights reserved. |
MG18C802 |
Product Overview |
Design Guide |
3.1.7Star/Delta Starter or Soft Starter not Required
When larger motors are started, it is necessary in many countries to use equipment that limits the start-up current. In more traditional systems, a star/delta starter or soft starter is widely used. Such motor starters are not required if a frequency converter is used.
As illustrated in Illustration 3.8, a frequency converter does not consume more than rated current.
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<![if ! IE]> <![endif]>175HA227.10 |
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Full load & speed
1VLT® HVAC Basic Drive FC 101
2Star/delta starter
3Soft starter
4Start directly on mains
Illustration 3.8 Start-up Current
3.1.8Using a Frequency Converter Saves Money
The example in chapter 3.1.9 Without a Frequency Converter shows that a frequency converter replaces other
equipment. It is possible to calculate the cost of installing 3 3 the 2 different systems. In the example, the 2 systems can
be established at roughly the same price.
Use the VLT® Energy Box software that is introduced in chapter 1.5 Additional Resources to calculate the cost savings that can be achieved by using a frequency converter.
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
17 |
Product Overview |
VLT® HVAC Basic Drive FC 101 |
3.1.9 Without a Frequency Converter
Cooling section |
Heating section |
Inlet guide vane |
Fan section |
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<![if ! IE]> <![endif]>175HA205.12 |
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Illustration 3.9 Traditional Fan System
18 |
Danfoss A/S © 04/2018 All rights reserved. |
MG18C802 |
Product Overview |
Design Guide |
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3.1.10 With a Frequency Converter
Cooling section |
Heating section |
Fan section |
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Variable air volume |
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Sensor P |
Pressure |
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Illustration 3.10 Fan System Controlled by Frequency Converters
3.1.11 Application Examples
The following sections give typical examples of applications within HVAC.
3.1.12 Variable Air Volume
VAV or variable air volume systems, control both the ventilation and temperature to ful€ll the requirements of a building. Central VAV systems are considered to be the most energy-efficient method to air condition buildings. By designing central systems instead of distributed systems, a greater efficiency can be obtained.
The efficiency comes from utilizing larger fans and larger chillers which have much higher efficiencies than small motors and distributed air-cooled chillers. Savings are also seen from the decreased maintenance requirements.
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
19 |
Product Overview |
VLT® HVAC Basic Drive FC 101 |
3.1.13 The VLT Solution
While dampers and IGVs work to maintain a constant pressure in the ductwork, a frequency converter solution saves much more energy and reduces the complexity of
3 3 the installation. Instead of creating an arti€cial pressure drop or causing a decrease in fan efficiency, the frequency converter decreases the speed of the fan to provide the flow and pressure required by the system.
Centrifugal devices such as fans behave according to the centrifugal laws. This means that the fans decrease the pressure and flow they produce as their speed is reduced. Their power consumption is thereby signi€cantly reduced. The PI controller of the VLT® HVAC Basic Drive FC 101 can be used to eliminate the need for additional controllers.
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Heating coil |
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Illustration 3.11 Variable Air Volume
<![endif]>130BB455.10
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Danfoss A/S © 04/2018 All rights reserved. |
MG18C802 |
Product Overview |
Design Guide |
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3.1.14 Constant Air Volume
CAV, or constant air volume systems, are central ventilation systems usually used to supply large common zones with the minimum amounts of fresh tempered air. They preceded VAV systems and are therefore found in older multi-zoned commercial buildings as well. These systems preheat amounts of fresh air utilizing air handling units (AHUs) with a heating coil, and many are also used to air condition buildings and have a cooling coil. Fan coil units are frequently used to assist in the heating and cooling requirements in the individual zones.
3.1.15 The VLT Solution
With a frequency converter, signi€cant energy savings can be obtained while maintaining decent control of the building. Temperature sensors or CO2 sensors can be used as feedback signals to frequency converters. Whether controlling temperature, air quality, or both, a CAV system can be controlled to operate based on actual building conditions. As the number of people in the controlled area decreases, the need for fresh air decreases. The CO2 sensor detects lower levels and decreases the supply fans speed. The return fan modulates to maintain a static pressure setpoint or €xed difference between the supply and return airflows.
With temperature control, especially used in air conditioning systems, as the outside temperature varies as well as the number of people in the controlled zone changes, different cooling requirements exist. As the temperature decreases below the setpoint, the supply fan
can decrease its speed. The return fan modulates to 3 3 maintain a static pressure setpoint. By decreasing the air
flow, energy used to heat or cool the fresh air is also reduced, adding further savings.
Several features of the Danfoss HVAC dedicated frequency converter can be utilized to improve the performance of the CAV system. One concern of controlling a ventilation system is poor air quality. The programmable minimum frequency can be set to maintain a minimum amount of supply air regardless of the feedback or reference signal. The frequency converter also includes a PI controller, which allows monitoring both temperature and air quality. Even if the temperature requirement is ful€lled, the frequency converter maintains enough supply air to satisfy the air quality sensor. The controller is capable of monitoring and comparing 2 feedback signals to control the return fan by maintaining a €xed differential airflow between the supply and return ducts as well.
Cooling coil |
Heating coil |
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Illustration 3.12 Constant Air Volume
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
21 |
Product Overview |
VLT® HVAC Basic Drive FC 101 |
3.1.16 Cooling Tower Fan
Cooling tower fans cool condenser-water in water-cooled chiller systems. Water-cooled chillers provide the most efficient means of creating chilled water. They are as much
3 3 as 20% more efficient than air cooled chillers. Depending on climate, cooling towers are often the most energy efficient method of cooling the condenser-water from chillers.
They cool the condenser water by evaporation.
The condenser water is sprayed into the cooling tower until the cooling towers €ll to increase its surface area. The tower fan blows air through the €ll and sprayed water to aid in the evaporation. Evaporation removes energy from the water dropping its temperature. The cooled water collects in the cooling towers basin where it is pumped back into the chillers condenser and the cycle is repeated.
Several features of the Danfoss HVAC dedicated frequency converter can be utilized to improve the performance of cooling tower fans applications. As the cooling tower fans drop below a certain speed, the effect the fan has on cooling the water becomes small. Also, when utilizing a gearbox to frequency control the tower fan, a minimum speed of 40–50% is required.
The customer programmable minimum frequency setting is available to maintain this minimum frequency even as the feedback or speed reference calls for lower speeds.
Also as a standard feature, the frequency converter can be programmed to enter a sleep mode and stop the fan until a higher speed is required. Additionally, some cooling tower fans have undesirable frequencies that may cause vibrations. These frequencies can easily be avoided by programming the bypass frequency ranges in the frequency converter.
3.1.17 The VLT Solution
With a frequency converter, the cooling tower fans can be controlled to the required speed to maintain the condenser-water temperature. The frequency converters can also be used to turn the fan on and off as needed.
<![if ! IE]><![endif]>130BB453.10
Frequency converter
Water Inlet
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Supply
Illustration 3.13 Cooling Tower Fan
22 |
Danfoss A/S © 04/2018 All rights reserved. |
MG18C802 |
Product Overview |
Design Guide |
|
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3.1.18 Condenser Pumps
Condenser water pumps are primarily used to circulate water through the condenser section of water cooled chillers and their associated cooling tower. The condenser water absorbs the heat from the chiller's condenser section and releases it into the atmosphere in the cooling tower. These systems are used to provide the most efficient means of creating chilled water, they are as much as 20% more efficient than air cooled chillers.
Using a frequency converter instead of a throttling valve |
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3.1.19 The VLT Solution
Frequency converters can be added to condenser water pumps instead of balancing the pumps with a throttling valve or trimming the pump impeller.
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Illustration 3.14 Condenser Pumps
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
23 |
Product Overview VLT® HVAC Basic Drive FC 101
3.1.20 Primary Pumps 3.1.21 The VLT Solution
Primary pumps in a primary/secondary pumping system can be used to maintain a constant flow through devices that encounter operation or control difficulties when
3 3 exposed to variable flow. The primary/secondary pumping technique decouples the primary production loop from the secondary distribution loop. This allows devices such as chillers to obtain constant design flow and operate properly while allowing the rest of the system to vary in flow.
As the evaporator flow rate decreases in a chiller, the chilled water begins to become overchilled. As this happens, the chiller attempts to decrease its cooling capacity. If the flow rate drops far enough, or too quickly, the chiller cannot shed its load sufficiently and the chiller’s safety trips the chiller requiring a manual reset. This situation is common in large installations especially when 2 or more chillers in parallel are installed if primary/ secondary pumping is not utilized.
Depending on the size of the system and the size of the primary loop, the energy consumption of the primary loop can become substantial.
A frequency converter can be added to the primary system to replace the throttling valve and/or trimming of the impellers, leading to reduced operating expenses. 2 control methods are common:
Flow meter
Because the desired flow rate is known and is constant, a flow meter installed at the discharge of each chiller, can be used to control the pump directly. Using the built-in PI controller, the frequency converter always maintains the appropriate flow rate, even compensating for the changing resistance in the primary piping loop as chillers and their pumps are staged on and off.
Local speed determination
The operator simply decreases the output frequency until the design flow rate is achieved.
Using a frequency converter to decrease the pump speed is very similar to trimming the pump impeller, except it does not require any labor, and the pump efficiency remains higher. The balancing contractor simply decreases the speed of the pump until the proper flow rate is achieved and leaves the speed €xed. The pump operates at this speed any time the chiller is staged on. Because the primary loop does not have control valves or other devices that can cause the system curve to change, and the variance due to staging pumps and chillers on and off is usually small, this €xed speed remains appropriate. If the flow rate needs to be increased later in the system’s life, the frequency converter can simply increase the pump speed instead of requiring a new pump impeller.
24 |
Danfoss A/S © 04/2018 All rights reserved. |
MG18C802 |
Product Overview |
Design Guide |
Flowmeter |
Flowmeter |
F |
F |
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<![if ! IE]> <![endif]>CHILLER |
Frequency Frequency converter converter
Illustration 3.15 Primary Pumps
<![endif]>130BB456.10
3 3
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
25 |
Product Overview |
VLT® HVAC Basic Drive FC 101 |
3.1.22 Secondary Pumps
Secondary pumps in a primary/secondary chilled water pumping system distribute the chilled water to the loads from the primary production loop. The primary/secondary
3 3 pumping system is used to hydronically de-couple 1 piping loop from another. In this case, the primary pump is used to maintain a constant flow through the chillers while allowing the secondary pumps to vary in flow, increase control and save energy.
If the primary/secondary concept is not used in the design of a variable volume system when the flow rate drops far enough or too quickly, the chiller cannot shed its load properly. The chiller’s low evaporator temperature safety then trips the chiller requiring a manual reset. This situation is common in large installations especially when 2 or more chillers in parallel are installed.
3.1.23 The VLT Solution
While the primary-secondary system with 2-way valves improves energy savings and eases system control problems, the true energy savings and control potential is realized by adding frequency converters.
With the proper sensor location, the addition of frequency converters allows the pumps to vary their speed to follow the system curve instead of the pump curve.
This results in the elimination of wasted energy and eliminates most of the overpressurization that 2-way valves can be subjected to.
As the monitored loads are reached, the 2-way valves close down. This increases the differential pressure measured across the load and the 2-way valve. As this differential pressure starts to rise, the pump is slowed to maintain the control head also called setpoint value. This setpoint value is calculated by summing the pressure drop of the load and the 2-way valve together under design conditions.
NOTICE
When running multiple pumps in parallel, they must run at the same speed to maximize energy savings, either with individual dedicated frequency converters or 1 frequency converter running multiple pumps in parallel.
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Illustration 3.16 Secondary Pumps
26 |
Danfoss A/S © 04/2018 All rights reserved. |
MG18C802 |
Product Overview |
Design Guide |
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3.2 Control Structures
Select [0] Open loop or [1] Closed loop in parameter 1-00 Configuration Mode.
3.2.1 Control Structure Open Loop
Reference handling Remote reference
Auto mode
Hand mode
Local reference scaled to Hz
LCP Hand on, o and auto on keys
P 4-14 Motor speed
high limit [Hz]
Remote
Reference
Local
P 4-12 Motor speed low limit [Hz]
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Illustration 3.17 Open-loop Structure
In the con€guration shown in Illustration 3.17,
parameter 1-00 Configuration Mode is set to [0] Open loop. The resulting reference from the reference handling system or the local reference is received and fed through the ramp limitation and speed limitation before being sent to the motor control. The output from the motor control is then limited by the maximum frequency limit.
3.2.2 PM/EC+ Motor Control
The Danfoss EC+ concept provides the possibility for using high-efficient PM motors (permanent magnet motors) in IEC standard enclosure sizes operated by Danfoss frequency converters.
The commissioning procedure is comparable to the existing one for asynchronous (induction) motors by utilizing the Danfoss VVC+ PM control strategy.
Customer advantages:
•Free choice of motor technology (permanent magnet or induction motor).
•Installation and operation as know on induction motors.
•Manufacturer independent when selecting system components (for example, motors).
•Best system efficiency by selecting best components.
•Possible retro€t of existing installations.
•Power range: 45 kW (60 hp) (200 V), 0.37–90 kW (0.5–121 hp) (400 V), 90 kW (121 hp) (600 V) for
induction motors and 0.37–22 kW (0.5–30 hp) (400 V) for PM motors.
Current limitations for PM motors:
•Currently only supported up to 22 kW (30 hp).
•LC €lters are not supported with PM motors.
•Kinetic back-up algorithm is not supported with PM motors.
•Support only complete AMA of the stator resistance Rs in the system.
•No stall detection (supported from software version 2.80).
3.2.3Local (Hand On) and Remote (Auto On) Control
The frequency converter can be operated manually via the local control panel (LCP) or remotely via analog/digital inputs or serial bus. If allowed in parameter 0-40 [Hand on] Key on LCP, parameter 0-44 [Off/Reset] Key on LCP, and parameter 0-42 [Auto on] Key on LCP, it is possible to start and stop the frequency converter via LCP by pressing [Hand On] and [Off/Reset]. Alarms can be reset via the [Off/Reset] key.
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Illustration 3.18 LCP Keys
3 3
MG18C802 |
Danfoss A/S © 04/2018 All rights reserved. |
27 |
Product Overview |
VLT® HVAC Basic Drive FC 101 |
Local reference forces the con€guration mode to openloop, independent on the setting of
parameter 1-00 Configuration Mode.
Local reference is restored at power-down.
3 3 3.2.4 Control Structure Closed Loop
The internal controller allows the frequency converter to become a part of the controlled system. The frequency converter receives a feedback signal from a sensor in the system. It then compares this feedback to a setpoint reference value and determines the error, if any, between these 2 signals. It then adjusts the speed of the motor to correct this error.
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7-30 PI
Normal/Inverse
Control
Illustration 3.19 Control Structure Closed-loop
While the default values for the closed-loop controller of the frequency converter often provide satisfactory performance, the control of the system can often be optimized by adjusting parameters.
For example, consider a pump application where the speed of a pump is to be controlled to ensure a constant static pressure in a pipe. The static pressure value is supplied to the frequency converter as the setpoint reference. A static pressure sensor measures the actual static pressure in the pipe and supplies this data to the frequency converter as a feedback signal. If the feedback signal is greater than the setpoint reference, the frequency converter slows the pump down to reduce the pressure. In a similar way, if the pipe pressure is lower than the setpoint reference, the frequency converter automatically speeds the pump up to increase the pressure provided by the pump.
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3.2.5 Feedback Conversion
In some applications, it may be useful to convert the feedback signal. One example of this is using a pressure signal to provide flow feedback. Since the square root of pressure is proportional to flow, the square root of the pressure signal yields a value proportional to the flow. See
Illustration 3.20.
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ow |
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Illustration 3.20 Feedback Signal Conversion
28 |
Danfoss A/S © 04/2018 All rights reserved. |
MG18C802 |