Danfoss VLT 6000 HVAC Profibus User manual

VLT®6000 HVAC
1MG.60.B1.02 - VLT is a registered Danfoss trademark
Introduction to
HVAC
Contents
■■
■■
■
Programming
All about
VLT 6000 HVAC Installation
IntrIntr
IntrIntr
Introduction to HVoduction to HV
oduction to HVoduction to HV
oduction to HVACAC
ACAC
AC
Software version .................................................................................................................. 3
Safety regulations ................................................................................................................ 4
Warning against unintended start ........................................................................................ 4
Introduction to the Design Guide......................................................................................... 5
Available literature ................................................................................................................ 7
Why use a frequency converter for controlling...................................................................... 8
fans and pumps?.................................................................................................................8
The clear advantage - energy savings .................................................................................. 8
Example with varying flow over 1 year .................................................................................. 9
Control principle ................................................................................................................ 12
PC software and serial communication .............................................................................. 15
CE-labelling ....................................................................................................................... 16
Application examples ......................................................................................................... 17
Specification text ............................................................................................................... 24
Ordering guide................................................................................................................... 30
Choice of frequency converter............................................................................................ 30
Unpacking and ordering a VLT frequency converter ........................................................... 34
Type code ordering number string...................................................................................... 34
Ordering form VLT 6000 HVAC .......................................................................................... 35
InstallationInstallation
InstallationInstallation
Installation
General technical data ....................................................................................................... 42
Mains supply 3 x 200 - 240 V............................................................................................ 45
Technical data, mains supply 3 x 380 - 460 V.................................................................... 46
Mechanical dimensions...................................................................................................... 48
Mechanical installation ....................................................................................................... 50
Enclosure protection.......................................................................................................... 50
Field-mounting .................................................................................................................. 50
General information about electrical installation.................................................................. 52
High voltage warning ......................................................................................................... 52
Earthing............................................................................................................................. 52
Cables ............................................................................................................................... 52
Screened/armouredcables ................................................................................................ 52
Extra protection ................................................................................................................. 52
RFI switch ......................................................................................................................... 53
High voltage test................................................................................................................ 53
Heat emission from VLT 6000 HVAC .................................................................................. 53
EMC-correct electrical installation ...................................................................................... 54
Use of EMC-correct cables ................................................................................................ 55
Earthing of screened/armoured control cables ................................................................... 56
VLT 6000 HVAC enclosures ............................................................................................... 57
Tightening-up torque and screw sizes ............................................................................... 62
Mains connection .............................................................................................................. 62
Pre-fuses........................................................................................................................... 62
Motor connection .............................................................................................................. 62
DC bus connection............................................................................................................ 64
High-voltage relay ..............................................................................................................64
Electrical installation, control cables ................................................................................... 65
Connection example, VLT 6000 HVAC ............................................................................... 66
Switches 1-4 ..................................................................................................................... 67

VLT® 6000 HVAC
MG.60.B1.02 - VLT is a registered Danfoss trademark
2
ProgrammingProgramming
ProgrammingProgramming
Programming
Control unit LCP................................................................................................................69
Quick menu ....................................................................................................................... 74
The Setup configuration .................................................................................................... 75
Setup of user-defined readout............................................................................................ 76
Load and Motor 100-117 .................................................................................................. 81
Configuration..................................................................................................................... 81
References & Limits 200 - 228........................................................................................... 88
Reference handling ............................................................................................................ 89
Inputs and outputs 300-328 ............................................................................................. 97
Analogue inputs .............................................................................................................. 100
Analogue/digital outputs.................................................................................................. 103
Relay outputs .................................................................................................................. 106
Application functions 400-427......................................................................................... 108
Sleepmode ..................................................................................................................... 109
PID for process control .................................................................................................... 113
PID overview.................................................................................................................... 115
Serial communication for FC protocol .............................................................................. 121
Protocols......................................................................................................................... 121
Telegram communication ................................................................................................. 121
Telegram build-up under FC protocol ............................................................................... 122
Data character (byte)........................................................................................................ 123
Process word .................................................................................................................. 127
Control word as per FC protocol...................................................................................... 127
Status word as per FC protocol ....................................................................................... 129
Serial communication 500 - 556 ...................................................................................... 132
Warning words 1+2 and Alarm word................................................................................ 140
Service functions 600-631............................................................................................... 142
All about VLAll about VL
All about VLAll about VL
All about VLT 6000 HVT 6000 HV
T 6000 HVT 6000 HV
T 6000 HVACAC
ACAC
AC
Status messages ............................................................................................................. 148
List of warnings and alarms ............................................................................................. 150
Aggressive environments................................................................................................. 156
Calculation of resulting reference ..................................................................................... 156
Extreme running conditions ............................................................................................. 158
Peak voltage on motor ..................................................................................................... 159
Derating for ambient temperature..................................................................................... 160
Efficiency.......................................................................................................................... 162
Definitions ....................................................................................................................... 167
Factory settings ............................................................................................................... 169
Index ............................................................................................................................... 175

VLT®6000 HVAC
3MG.60.B1.02 - VLT is a registered Danfoss trademark
Introduction to
HVAC
This Design Guide can be used with all VLT 6000 HVAC fre-
quency converters that have software version 1.0x.
See software version number in parameter 624 Software ver-
sion no.
VLT6000 HVAC
DesignGuide
Software version: 1.0x

VLT® 6000 HVAC
MG.60.B1.02 - VLT is a registered Danfoss trademark
4
Warning:
Touching the electrical parts may be fatal - even after the
equipment has been disconnected from mains.
Using VLT 6001-6005: wait at least 4 minutes
Using VLT 6006-6275: wait at least 15 minutes
The voltage of the frequency converter
is dangerous whenever the equipment
is connected to mains. Incorrect instal-
lation of the motor or the frequency converter may
cause damage to the equipment, serious personal
injury or death.
Consequently, the instructions in this manual, as
well as national and local rules and safety
regulations, must be complied with.
■■
■■
■Safety regulations
1. The VLT frequency converter must be discon-
nected from mains if repair work is to be carried
out.
Check that the mains supply has been
disconnected and that the necessary time has
passed before removing motor and mains plugs.
2. The [OFF/STOP] key on the control panel of the
VLT frequency converter does not disconnect the
equipment from mains and is thus not to be used
as a safety switch.
3. Correct protective earthing of the equipment must
be established, the user must be protected
against supply voltage, and the motor must be
protected against overload in accordance with
applicable national and local regulations.
4. The earth leakage currents are higher than 3.5 mA.
5. Protection against motor overload is not included
in the factory setting. If this function is required,
set parameter 117, Motor thermal protection, to
data value ETR trip or data value ETR warning.
Note: The function is initialised at 1.0 x rated
motor current and rated motor frequency (see
page 87).
For the North American market: The ETR
functions ensure overload protection of the motor,
Class 20, in accordance with NEC.
6. Do not remove the plugs for the motor and mains
supply while the VLT frequency converter is
connected to mains. Check that the mains supply
has been disconnected and that the necessary
time has passed before removing motor and
mains plugs.
7. Reliable galvanic isolation (PELV) is not complied
with if the RFI switch is placed in OFF position.
This means that all control in- and outputs can no
longer be considered low-voltage terminals.
8. Please note that the VLT frequency converter has
more voltage inputs than L1, L2, L3 when the DC-
bus terminals are used.
Check that all voltage inputs have been
disconnected and that the necessary time has
passed before repair work is commenced.
■■
■■
■Warning against unintended start
1. The motor can be brought to a stop by means of
digital commands, bus commands, references or a
local stop, while the frequency converter is
connected to mains.
If personal safety considerations make it
necessary to ensure that no unintended start
occurs, these stop functions are not sufficient.
2. While parameters are being changed, the motor
may start. Consequently, the stop key [OFF/
STOP] must always be activated, following which
data can be modified.
3. A stopped motor may start if a fault occurs in the
electronics of the VLT frequency converter, or if a
temporary overload or a fault in the supply mains
or the motor connection ceases.

VLT®6000 HVAC
5MG.60.B1.02 - VLT is a registered Danfoss trademark
Introduction to
HVAC
■■
■■
■Introduction to the Design Guide
This Design Guide is a tool intended to facilitate the sizing of systems in which VLT 6000 HVAC frequency
converters are used.
HVAC stands for Heating Ventilation Air-Conditioning.
This Design Guide progresses step-by-step through the different procedures required for selecting, installing and
programming a VLT 6000 HVAC.
The Design Guide forms part of the literature concept supplied with VLT 6000 HVAC. However, the Design Guide
is the most comprehensive document available.
When a VLT 6000 HVAC is supplied, it is accompanied by Operating Instructions and a Quick Setup Guide. See
next page Other literature.
Operating Instructions:Operating Instructions:
Operating Instructions:Operating Instructions:
Operating Instructions: Describe how to ensure optimum mechanical and electrical installation, and
also deal with commissioning and service. The Operating Instructions
furthermore provide a description of the software parameters, thereby
ensuring that you can easily fit the VLT 6000 HVAC into your application.
Quick Setup Guide:Quick Setup Guide:
Quick Setup Guide:Quick Setup Guide:
Quick Setup Guide: Helps you get your VLT 6000 HVAC installed and commissioned quickly.
Design Guide:Design Guide:
Design Guide:Design Guide:
Design Guide: Used when designing systems with VLT 6000 HVAC. The Design Guide gives
all useful information about the VLT 6000 HVAC and HVAC systems. There is
a selection tool for you to choose the right VLT 6000 HVAC with the relevant
options and modules. The Design Guide has examples of the most common
types of HVAC applications. In addition, the Design Guide has all information
relating to Serial Communication.
This Design Guide is split in four sections that have information about VLT 6000 HVAC.
Introduction to HVAC:Introduction to HVAC:
Introduction to HVAC:Introduction to HVAC:
Introduction to HVAC: This section tells you the advantages that can be obtained by using
frequency converters in HVAC systems. Furthermore, you can read about the
way a frequency converter operates and about the advantages of the VLT
6000 HVAC, such as AEO - Automatic Energy Optimisation, RFI filter and
other HVAC-relevant functions.
There are also examples of applications and information is given about
Danfoss and CE-labelling.
The specification section deals with the requirements relating to being
allowed to supply and install frequency converters. This section can be used
in contract documents, whereby the total list of requirements relating to
frequency converters is determined.
The section ends with an Ordering Guide that makes it easier for you to
specify and order a VLT 6000 HVAC.

VLT® 6000 HVAC
MG.60.B1.02 - VLT is a registered Danfoss trademark
6
Installation:Installation:
Installation:Installation:
Installation: This section shows you how to carry out correct mechanical installation of a
VLT 6000 HVAC.
In addition, the section has a description of how you ensure that the
installation of the VLT 6000 HVAC is EMC-correct. Furthermore, the section
includes a list of mains and motor connections, as well as a description of
control card terminals.
Programming:Programming:
Programming:Programming:
Programming: This section describes the control unit and the software parameters for the
VLT 6000 HVAC. There is also a guide to the Quick Setup menu, which
means that you will be able to start using your application very quickly.
All about VLAll about VL
All about VLAll about VL
All about VLT 6000:T 6000:
T 6000:T 6000:
T 6000: This section has information about status, warning and fault indications from
the VLT 6000 HVAC. In addition, the section has technical data, service
information, factory settings and information on special conditions.
■■
■■
■Introduction to the Design Guide
This symbol indicates a general
warning. This symbol indicates a high-
voltage warning.
This symbol indicates something
to be noted by the reader.

VLT®6000 HVAC
7MG.60.B1.02 - VLT is a registered Danfoss trademark
Introduction to
HVAC
■■
■■
■Available literature
The chart below gives an overview of the literature available for the VLT 6000 HVAC.
Please note that variations may occur from one country to the next
Design
Guide
MG.60.BX.YY
Operating
Instructions
MG.60.AX.YY
Comes
with
VLT 6000
HVAC
Software
Dialog
MG.50.EX.YY
PROFIBUS
Manual
MG.10.EX.YY
Quick
Setup
MG.60.CX.YY
LCP Remote
controlunit
MI.56.AX.51
LC-filter
MI.56.DX.51
IP20terminal
cover
MI.56.CX.51
Metasys N2
VLT6000 HVAC
Data sheet
MD.60.AX.YY
Other literature
for VLT 6000
HVAC
Instructions
for VLT
6000 HVAC
Communication
with VLT 6000
HVAC
LonWorks
Manual
Relay card
instructions
MI.66.BX.YY
Landis/Staefa
FLN
RCD
instructions
MI.66.AX.YY
X = version number
YY = language version
01 = Danish
02 = English
03 = German
04 = French
05 = Spanish
06 = Italian
07 = Swedish
10 = Dutch
20= Finnish
28 = Brazilian-Portuguese
51,52 = Danish, English, German

VLT® 6000 HVAC
MG.60.B1.02 - VLT is a registered Danfoss trademark
8
Why use a frequency converter for controlling
fans and pumps?
A frequency converter takes advantage of the fact that
centrifugal fans and pumps follow the laws of
proportionality for such fans and pumps.
The graph below describes the laws of proportionality.
The graph shows that flow and pressure can be re-
gulated by changing the rpm figure.
■■
■■
■
The laws of proportionality
This figure describes the dependence of flow, pres-
sure and power consumption on the rpm figure.
Q = Flow
Q1= Rated flow
Q2= Reducing flow
H = Pressure
H1= Rated pressure
H2 = Reducing pressure
P = Power
P1= Rated power
P2= Reducing power
n = Speed regulation
n1= Rated speed
n2= Reducing speed
The clear advantage - energy savings
The very clear advantage of using a frequency conver-
ter for controlling the speed of fans or pumps lies in
the electricity savings to be obtained.
When comparing with alternative regulating systems
and technologies, a frequency converter is the opti-
mum energy control system for regulating fan and
pump systems.
Example of energy savings
As can be seen from the figure (the laws of propor-
tionality), the flow is regulated by changing the rpm
figure. By reducing the speed only 20% from the rated
speed, the flow is also reduced by 20%. This is
because the flow is directly proportional to the rpm
figure. 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%.
■■
Flow: Q1 =n1
Pressure: H1=(n1)2
Power: P1=(n1)3
Q2 n2
H2n2
P2n2

VLT®6000 HVAC
9MG.60.B1.02 - VLT is a registered Danfoss trademark
Introduction to
HVAC
Example with varying flow over 1 year
The example below is calculated on the basis of pump
characteristics obtained from a pump data-sheet. (45
kW). The same examples of calculations can be used
in the case of fan characteristics.
The result obtained is savings in excees of 50% at the
■
Energy savings
This figure compares flow regulation via valves and
without speed control with flow regulation via a
frequency converter.
Pshaft = Pshaft output
Flow distribution over 1 year
given flow distribution over a year, corresponding to
8,760 hours.
Typically, the example calculated below results in a
pay-back period of one year - depending on the price
per kWh and the price of the frequency converter.
m3/t Distribution Valve regulation Frequencyconverter control
% Hours Power Consumption Power Consumption
A1- B1kWh A1 - C1kWh
350 5 438 42,5 18.615 42,5 18.615
300 15 1314 38,5 50.589 29,0 38.106
250 20 1752 35,0 61.320 18,5 32.412
200 20 1752 31,5 55.188 10,0 17.520
150 20 1752 28,0 49.056 6,5 11.388
100 20 1752 23,0 40.296 3,5 6.132
ΣΣ
ΣΣ
Σ100100
100100
100 87608760
87608760
8760 275.064275.064
275.064275.064
275.064 124.173124.173
124.173124.173
124.173
Pump characteristics

VLT® 6000 HVAC
MG.60.B1.02 - VLT is a registered Danfoss trademark
10
■■
■■
■Better regulation
If a frequency converter is used for regulating the flow
or pressure of a system, improved regulation is
obtained which can be adjusted very precisely.
A frequency converter can vary the speed of the fan or
pump infinitely, thereby obtaining infinitely variable
control of flow and pressure.
Furthermore, a frequency converter can quickly
regulate the speed of the fan or pump, so as to adapt
it to new flow or pressure conditions in the system.
More traditional, mechanical flow or pressure
regulating systems tend to provide slow, inaccurate
regulation if compared with that of the frequency
converter.
■■
■■
■Frequency converters generate less noise
If the speed of a fan is changed, the sound level
changes, too. If the rpm figure is reduced by 50%
from the rated rpm value, the sound level will go down
by approx. 16 dB(A).
The formula is:
55 log x ( ) = dB(A)
■■
■■
■Simpler installation when using a frequency con-
verter
A frequency converter can replace a traditional
regulating system, in which mechanical dampers and
valves are used for regulating flow or pressure.
The great advantage involved in using a frequency
converter is that the system becomes simpler, since a
lot of the mechanical and electrical equipment is no
longer required.
■■
■■
■V-belts no longer required
In mechanical regulating systems, where the fan is
driven by V-belts, it is necessary to change belt
pulleys in order to adjust the fan speed to match the
neces-sary maximum load. Using a frequency conver-
ter, the V-belts can be replaced by directly driven mo-
tors, whose speed is changed simply by means of the
frequency converter.
The efficiency of the system improves and the entire
installation takes up less space. There is no dust from
the V-belt and less maintenance.
■■
■■
■Regulating dampers and valves no longer
required
Since the flow or pressure can be regulated by
means of the frequency converter, no regulating
dampers and valves are required in the system.
■■
■■
■Cos ϕϕ
ϕϕ
ϕcompensation
Generally speaking, a frequency converter with a cos
of 1 provides power factor correction for the cos ϕof
the motor, which means that there is no need to
make allowance for the cos ϕof the motor when
sizing the power factor correction unit.
■■
■■
■Star/delta starter or soft-starter not required
When larger motors are started, it is necessary in
many countries to use equipment that limits the
start-up current. In more traditional systems, a star/
delta starter or soft-starter is widely used. Such
motor starters are not required if a frequency conver-
ter is used.
As illustrated in the figure below, a frequency conver-
ter does not consume more than rated current.
1 = VLT 6000 HVAC
2 = Star/delta starter
3 = Soft-starter
4 = Start directly on mains
■■
■■
■Cost of using frequency converter not higher
The example on the following page shows that a lot
of equipment is not required when a frequency
converter is used. It is possible to calculate the cost
of installing the two different systems. In the example
on the following page, the two systems can be
established at roughly the same price.
n1
n2

VLT®6000 HVAC
11MG.60.B1.02 - VLT is a registered Danfoss trademark
Introduction to
HVAC
WW
WW
Without a frithout a fr
ithout a frithout a fr
ithout a frequency converterequency converter
equency converterequency converter
equency converter
The figure shows a fan system made in the traditional
way.
WW
WW
With a frith a fr
ith a frith a fr
ith a frequency converterequency converter
equency converterequency converter
equency converter
The figure shows a fan system controlled by VLT 6000 HVAC frequency converters.
■
■
D.D.C. = Direct Digital Control
E.M.S. = Energy Management System
V.A.V. = Variable Air Volume
Sensor P = Pressure
Sensor T = Temperature

VLT® 6000 HVAC
MG.60.B1.02 - VLT is a registered Danfoss trademark
12
1. Mains voltage
3 x 200 - 240 V AC, 50 / 60 Hz
3 x 380 - 460 V AC, 50 / 60 Hz.
2. Rectifier
A three-phase rectifier bridge that rectifies AC
into DC current.
3. Intermediate circuit
DC voltage = √2 x mains voltage [V].
4. Intermediate circuit coils
Smooth the intermediate circuit current and limit
the repercussive effect of harmonic currents on
the mains supply.
5. Intermediate circuit capacitors
Smooth the intermediate circuit voltage.
6. Inverter
Converts DC voltage into variable AC voltage
with a variable frequency.
7. Motor voltage
Variable AC voltage, 10-100% of the supply
voltage.
8. Control card
This is where to find the microprocessor that
controls the inverter which generates the pulse
pattern by which the DC voltage is converted into
variable AC voltage with a variable frequency.
■■
■■
■Control principle
A frequency converter rectifies AC mains voltage into
DC voltage, after which the DC voltage is converter
into an AC current with a variable amplitude and
frequency.
The motor is thus supplied with variable voltage and
frequency, which enables infinitely variable speed
regulation of three phase, asynchronous standard
motors.
The development of the VVCPLUS principle is the result
of a wish to maintain robust, sensorless regulation
that is tolerant to different motor characteristics
without motor derating being required.
First and foremost, the current measurement and the
motor model have been improved. The current is split
into magnetising and torque-generating parts and
provides for much better and quicker estimation of
the actual motor loads. It is now possible to
compensate much better for frequent load changes.
VVCPLUS control principle
The VLT 6000 HVAC has an inverter system called
VVCPLUS, i.e. a further development of Voltage Vector
Control (VVC). This principle is known from such
units as Danfoss VLT 3500 HVAC.
VVCPLUS controls an induction motor by energizing it
with a variable frequency and a voltage that matches
it. If the motor load is changed, the magnetisation
and speed of the motor change too. Consequently,
the motor current is measured continuously and the
actual voltage requirement and slip of the motor are
calculated from a motor model. Motor frequency and
voltage are adjusted to ensure that the motor
operating point remains optimised under varying
conditions.

VLT®6000 HVAC
13MG.60.B1.02 - VLT is a registered Danfoss trademark
Introduction to
HVAC
Good torque control properties, smooth transition to
current limit operation and robust pull-out protection
are ensured.
After automatic motor adaptation, VVCPLUS will help to
ensure extremely accurate motor control.
Because of the good load estimation achieved, an
energy optimisation algorithm can be integrated - one
that is effective regardless of the load characteristic.
Advantages of the V V CPLUS control system:
- Good compensation for step loads
- Great tolerance towards varying motor
charateristics
- Controlled transition from normal operation to
current limit operation (and vice versa)
- Quick response from speed reference to full motor
shaft torque
- Reliable pull-out torgue protection throughout the
speed range, also in the case of field weakening
- Torque control, comprising control of both the
torque-generating and the magnetising
component of the current
As standard, VLT 6000 HVAC comes with a number
of integral components that would normally have to
be acquired separately. These integral components
are space-savers that simplify installation, since VLT
6000 HVAC fulfills most requirements without any
additional components.
The use of a VLT 6000 HVAC offers the following
additional advantages:
- All unit types are available with an integral RFI
filter, complying with EN 55011 class 1-A in the
case of a 150 m screened/armoured motor cable
and EN 55011 class 1-B in the case of a
screened/armoured motor cable up to 50 m long.
- Detachable LCP control panel with Hand-Off-Auto
buttons and a graphics display of local speed.
- Automatic Motor Adaptation (AMA) ensures
optimum motor performance.
- Integral PID regulator with option of connecting
two feedback signals (in connection with zoning),
as well as setting of two set-points.
- Sleep mode, which automatically turns the motor
off, e.g. when there is no need for more pressure
or flow in a system.
Programmable control inputs and
signal outputs in four Setups
VLT 6000 HVAC uses a digital technique which
makes it possible to program the different control
inputs and signal outputs and to select four different
user-defined Setups for all parameters.
For the user, it is easy to program the required
functions by means of the control panel on VLT 6000
HVAC or via serial communication.
Protection against mains interference
VLT 6000 HVAC is protected against the transients
that occur in the mains supply, e.g. when switching
power factor correction or if fuses blow when
lightning strikes.
The rated motor voltage and full torque can be
maintained all the way down to 10% undervoltage in
the mains supply.
Minor interference on mains
Since as standard the VLT 6000 HVAC features
intermediate circuit coils, there is only a small amount
of harmonic mains supply interference. This ensures a
good power factor (lower peak current), which
reduces the load on the mains installation.
- The "flying start" function enables the unit to
catch a rotating fan.
- Automatic ramp up/down to ensure that the
VLT 6000 HVAC will not trip during acceleration
or deceleration.
- All standard units have three integral, serial
protocols - RS 485 FC protocol, Johnson’s
Metasys N2 and Landis/Staefa FLN.
Communication option cards that can be
connected are LonWorks, Profibus for the VLT
6000 HVAC.

VLT® 6000 HVAC
MG.60.B1.02 - VLT is a registered Danfoss trademark
14
Advanced motor protection
VLT 6000 HVAC features integrated electronic,
thermal motor protection.
The frequency converter calculates the motor
temperature on the basis of current, frequency and
time.
As opposed to the traditional bimetallic protection,
electronic protection takes account of the reduction
in cooling at low frequencies that comes from
reduced fan speed (motors with internal ventilation).
Thermal motor protection is comparable to a normal
motor thermistor.
To obtain maximum protection against overheating of
the motor if the motor is covered or blocked, or if the
fan fails, a thermistor can be integrated and
connected to the thermistor input of the frequency
converter (terminals 53/54), see parameter 117 Motor
thermal protection.
Advanced VLT protection
Current measurement on all three motor phases
provides perfect protection of VLT 6000 HVAC against
earthing and short-circuiting faults on the motor
connection.
Constant monitoring of the three motor phases
enables switching on the motor output, e.g. by
means of a contactor.
Efficient monitoring of the three mains supply phases
ensures that the unit trips in the case of phase failure.
This avoids overloading the inverter and the
capacitors in the intermediate circuit, which would
dramatically reduce the service life of the frequency
converter.
As standard, VLT 6000 HVAC features integral
temperature protection. If a thermal overload occurs,
this function cuts out the inverter.
Reliable galvanic isolation
In the VLT 6000 HVAC, all control terminals as well as
terminals 1-5 (AUX relays) are supplied by or
connected to circuits that comply with PELV
requirements in relation to the mains potential.
AEO - Automatic Energy Optimization
Normally, the U/f characteristics have to be set on the
basis of the expected load at different frequencies.
However, knowing the load at a given frequency in an
installation is often a problem. This problem can be
solved by using a VLT 6000 HVAC with its integral
Automatic Energy Optimization (AEO), which ensures
optimum energy utilization. All VLT 6000 HVAC units
feature this function as a factory setting, i.e. it is not
necessary to adjust the frequency converter U/f ratio
in order to obtain maximum energy savings. In other
frequency converters, the given load and voltage/
frequency ratio (U/f) must be assessed to carry out
correct setting of the frequency converter.
Using Automatic Energy Optimization (AEO), you no
longer need to calculate or assess the system
characteristics of the installation, since Danfoss VLT
6000 HVAC units guarantee optimum, load-
dependent energy consumption by the motor at all
times.
The figure illustrates the working range of the AEO
function, within which energy optimization is enabled.
If the AEO function has been selected in parameter
101, Torque characteristics, this function will be
constantly active. If there is a major deviation from the
optimum U/f ratio, the VLT frequency converter will
quickly adjust itself.
Advantages of the AEO function
• Automatic energy optimization
• Compensation if an oversize motor is used
• AEO matches operations to daily or seasonal
fluctuations
• Energy savings in a constant air volume system
• Compensation in the oversynchronous working
range
• Reduces acoustic motor noise

VLT®6000 HVAC
15MG.60.B1.02 - VLT is a registered Danfoss trademark
Introduction to
HVAC
PC software and serial communication
Danfoss offers various options for serial communi-
cation. Using serial communication makes it possible
to monitor, programme and control one or several VLT
6000 HVAC from a centrally placed computer. For
example, Danfoss offers an option card for Profibus.
In addition, all VLT 6000 HVAC have an RS 485 port
as standard, which enables them to communicate
e.g. with a PC. A programme entitled VLT Software
Dialog is available for this purpose.
VLT Software Dialog comes in three modules and - as
a minimum - contains the programmes included in
the Basic module.
The Basic module covers:
TEST RUN
is used for controlling and commissioning of
a frequency converter, including:
- setting of reference value,
- simultaneous display of selected
parameters in graphs,
- option of DDE link, e.g. to a spreadsheet.
PARAMETER SETUP
is used for setting up and transferring para-
meter sets, including:
- setting of frequency converter parameters,
- parameter sets can be obtained from and
copied to a frequency converter,
- documentation/print-out of the Setup
including diagrams.
HISTORY
provides information about the different
stages of development of the VLT Software
dialogue.
BUS ADDRESS SETUP
is only used for addressing the VLT FCM.
The Logging module covers:
■LOGGING
is used for collecting and displaying historical or
real-time operating data.
- graphical representation of selected
parameters from several frequency
converters,
- collection of log data to file,
- option of DDE link e.g. to a spreadsheet.
MODEMSETUP
is used for setting up the frequency converter
modem.
- sets the frequency converter modem via the
communication port of the PC.
The template module covers:
TEMPLATE SETUP
is used for setting up template files for
PARAMETER SETUP:
- the template file functions as a mask that
limits the number of accessible parameters
when a parameter file is to be made or edited
in PARAMETER SETUP,
- the template file may contain preset values for
the parameters of the frequency converter.
NB! The logging and template module calls for a
Basic module to be installed on the same PC.
The guided tour covers:
GUIDED TOUR
offers a demonstration of the VLTSoftware
Dialog programme.

VLT® 6000 HVAC
MG.60.B1.02 - VLT is a registered Danfoss trademark
16
■■
■■
■CE-labelling
What is CE-labelling ?What is CE-labelling ?
What is CE-labelling ?What is CE-labelling ?
What is CE-labelling ?
The purpose of CE-labelling is to avoid technical
obstacles to trade 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 quality or specifications of a product.
Three EU directives relate to frequency converters:
••
••
•The machine directive (89/392/EEC)The machine directive (89/392/EEC)
The machine directive (89/392/EEC)The machine directive (89/392/EEC)
The machine directive (89/392/EEC)
All machines with critical, moving parts are
comprised by the machine directive which
came into force on 1 January 1995. Since a
frequency converter is largely electrical by
function, it does not fall under the machine
directive. However, if a frequency converter is
supplied for use in a machine, we provide
information about the safety aspects relating
to the frequency converter. We do that by
means of a manufacturer’s declaration.
••
••
•The low voltage directive (73/23/EEC)The low voltage directive (73/23/EEC)
The low voltage directive (73/23/EEC)The low voltage directive (73/23/EEC)
The low voltage directive (73/23/EEC)
Frequency converters must be CE-labelled in
accordance with the low voltage directive
which came into force on 1 January 1997.
This directive applies to all electrical
equipment and units used in the 50-1000 V
AC and 75-1500 V DC voltage ranges.
Danfoss provides its units with CE-labels in
accordance with the directive and issues
declarations of conformity upon request.
••
••
•The EMC directive (89/336/EEC)The EMC directive (89/336/EEC)
The EMC directive (89/336/EEC)The EMC directive (89/336/EEC)
The EMC directive (89/336/EEC)
EMC is short for electromagnetic compatibility.
The presence of electromagnetic compatibility
means that the mutual interference between
different components/appliances is so small that
the functioning of the appliances is not affected.
The EMC directive came into force on 1 January
1996. In accordance with the directive, Danfoss
CE-labels its products and issues a declaration
of conformity upon request.
To help ensure that your installation is EMC-correct,
the manual provides detailed instructions for
installation. Furthermore, we specify which norms
that are complied with by which of our products. We
offer the filters that can be seen from the
specifications and gladly provide other types of
assistance that can help you obtain the best possible
EMC result.
In most cases the VLT frequency converter is used by
professionals of the trade as a complex component
forming part of a larger appliance, system or
installation. It must be noted that the responsibility for
the final EMC properties of the appliance, system or
installation rests with the installer.

VLT®6000 HVAC
17MG.60.B1.02 - VLT is a registered Danfoss trademark
Introduction to
HVAC
■■
■■
■Application examples
The next few pages give typical examples of
applications within HVAC.
If you would like to receive further information about a
given application, please ask your Danfoss supplier
for an information sheet that gives a full description of
the application.
Variable Air Volume ........................................................................................................ page 18
Ask for The Drive to...Improving Variable Air Volume Ventilation systems MN.60.A1.02
Constant Air Volume ....................................................................................................... page 19
Ask for The Drive to...Improving Constant Air Volume Ventilation systems MN.60.B1.02
Cooling Tower Fan.......................................................................................................... page 20
Ask for The Drive to...Improving fan control on cooling towers MN.60.C1.02
Condenser pumps ......................................................................................................... page 21
Ask for The Drive to...Improving condenser water pumping systems MN.60.F1.02
Primary pumps............................................................................................................... page 22
Ask for The Drive to...Improve your primary pumping in primay/secondary
pumping systems MN.60.D1.02
Secondary pumps.......................................................................................................... page 23
Ask for The Drive to...Improve your secondary pumping in primay/secondary
pumping systems MN.60.E1.02

VLT® 6000 HVAC
MG.60.B1.02 - VLT is a registered Danfoss trademark
18
■■
■■
■Variable Air Volume
VAV or Variable Air Volume systems, are used to
control both the ventilation and temperature to satisfy
the requirements of a building. Central VAV systems
are considered to be the most energy efficient
method to air condition buildings. By designing
central systems instead of distributed systems, a
greater efficiency can be obtained.
The efficiency comes from utilizing larger fans and
larger chillers which have much higher efficiencies
than small motors and distributed air-cooled chillers.
Savings are also seen from the decreased main-
tenance requirements.
■■
■■
■The new standard
While dampers and IGVs work to maintain a constant
pressure in the ductwork, a VLT frequency converter
solution saves much more energy and reduces the
complexity of the installation. Instead of creating an
artificial pressure drop or causing a decrease in fan
efficiency, the VLT 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 the fans decrease
the pressure and flow they produce as their speed is
reduced. Their power consumption is thereby
significantly reduced.
The return fan is frequently controlled to maintain a
fixed difference in airflow between the supply and
return. The advanced PID controller of the VLT 6000
HVAC can be used to eliminate the need for addi-
tional controllers.
Pressure
signal
VAV boxes
Flow
Flow
Cooling coil Heating coil
D1
D2
D3
Filter
Pressure
transmitter
Supply fan
Return fan
T
3
3

VLT®6000 HVAC
19MG.60.B1.02 - VLT is a registered Danfoss trademark
Introduction to
HVAC
■■
■■
■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
therefore are found in older multi-zoned commercial
buildings as well. These systems preheat amounts of
fresh air utilizing Air Handling Units (AHUs) with a
heating coil, and many are also used to air condition
buildings and have a cooling coil. Fan coil units are
frequently used to assist in the heating and cooling
requirements in the individual zones.
■■
■■
■The new standard
With a VLT frequency converter, significant energy
savings can be obtained while maintaining decent
control of the building. Temperature sensors or CO2
sensors can be used as feedback signals to VLT
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 fixed difference
between the supply and return air flows.
Several features of Danfoss HVAC dedicated VLT
frequency converter, the VLT 6000 HVAC can be
utilized to improve the performance of your 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 VLT frequency converter also
includes a two zone, 2 setpoint PID controller which
allows monitoring both temperature and air quality.
Even if the temperature requirement is satisfied, the
drive will maintain enough supply air to satisfy the air
quality sensor. The controller is capable of monitoring
and comparing two feedback signals to control the
return fan by maintaining a fixed differential air flow
between the supply and return ducts as well.
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 require-
ments exist. As the temperature decreases below the
setpoint, the supply fan can decrease its speed. The
return fan modulates to maintain a static pressure
setpoint. By decreasing the air flow, energy used to
heat or cool the fresh air is also reduced, adding
further savings.
Pressure
signal
Cooling coil Heating coil
D1
D2
D3
Filter
Pressure
transmitter
Supply fan
Return fan
Temperature
signal
Temperature
transmitter

VLT® 6000 HVAC
MG.60.B1.02 - VLT is a registered Danfoss trademark
20
Water Inlet
Water Outlet
CHILLER
Temperature
Sensor
BASIN
Conderser
Water pump
Supply
■■
■■
■Cooling Tower Fan
Cooling Tower Fans are used to cool condenser
water in water cooled chiller systems. Water cooled
chillers provide the most efficient means of creating
chilled water. They are as much as 20% more efficient
than air cooled chillers. Depending on climate,
Cooling towers are often the most energy efficient
method of cooling the condenser water from chillers.
They cool the condenser water by evaporation.
The condenser water is sprayed into the cooling
tower onto the cooling towers “fill” to increase its
surface area. The tower fan blows air through the fill
and sprayed water to aid in the evaporation.
Evaporation removes energy from the water dropping
its temperature. The cooled water collects in the
cooling towers basin where it is pumped back into
the chillers condenser and the cycle is repeated.
■■
■■
■The new standard
With a VLT frequency converter, the cooling towers
fans can be controlled to the required speed to
maintain the condenser water temperature. VLT
frequency converters can also be used to turn the fan
on and off as needed.
Several features of Danfoss HVAC dedicated drive, the
VLT 6000 HVAC can be utilized to improve the
performance of your cooling tower fans application.
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 gear-box to VLT
frequency converter the tower fan, a minimum speed
of 40-50% may be required.
The customer programmable minimum frequency
setting of the VLT is available to maintain this
minimum frequency even as the feedback or speed
reference calls for lower speeds.
Also as a standard feature, you can program the VLT
frequency converter to enter a “sleep” mode and stop
the fan until a higher speed is required. Additionally,
some cooling tower fans have undesireable
frequencies that may cause vibrations. These
frequencies can easily be avoided by programming the
bypass frequency ranges in the VLT frequency
converter.