This design guide is intended for project and systems
engineers, design consultants, and application and product
specialists. Technical information is provided to understand
the capabilities of the frequency converter for integration
into motor control and monitoring systems. Details
concerning operation, requirements, and recommendations
for system integration are described. Information is
provided for input power characteristics, output for motor
control, and ambient operating conditions for the
frequency converter.
Also included are safety features, fault condition
monitoring, operational status reporting, serial communication capabilities, and programmable options. Design
details such as site requirements, cables, fuses, control
wiring, the size and weight of units, and other critical
information necessary to plan for system integration is also
provided.
Reviewing the detailed product information in the design
stage enables developing a well-conceived system with
optimal functionality and
eciency.
The VLT® Frequency Converters – Safe Torque O
•
Operating Guide contains safety guidelines and
describes the operation and specications of the
Safe Torque O function.
The VLT ® Brake Resistor MCE 101 Design Guide
•
describes how to select the proper brake resistor
for any application.
The VLT ® FC-Series Output Filter Design Guide
•
describes how to select the proper output lter
for any application.
The VLT® Parallel Drive Modules Busbar Kit Instal-
•
lation Instructions contain detailed information
about installing the busbar option kit.
The VLT® Parallel Drive Modules Duct Kit Instal-
•
lation Instructions contain detailed information
about installing the duct option kit.
Supplementary publications and manuals are available
from Danfoss. See drives.danfoss.com/knowledge-center/technical-documentation/ for listings.
11
VLT® is a registered trademark.
Additional Resources
1.2
Resources available to understand advanced frequency
converter functions and programming:
The VLT® Parallel Drive Modules 250–1200 kW
•
Installation Guide provides instructions for
mechanical and electrical installation of these
drive modules.
The VLT® Parallel Drive Modules 250–1200 kW User
•
Guide contains detailed procedures for start-up,
basic operational programming, and functional
testing. Additional information describes the user
interface, application examples, troubleshooting,
and specications.
Refer to the FC 102, FC 202, or FC 302 VLT ® Drive
•
Programming Guide applicable to the particular
series of VLT® Parallel Drive Modules used in
creating the drive system. The programming
guide describes in greater detail how to work
with parameters and provides application
examples.
The VLT ® FC Series, D-frame Service Manual
•
contains detailed service information, including
information applicable to the VLT® Parallel Drive
Modules.
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.
NOTICE
Indicates important information, including situations that
can result in damage to equipment or property.
2.2 Qualied Personnel
WARNING
DISCHARGE TIME
The drive module contains DC-link capacitors. Once
mains power has been applied to the drive, these
capacitors can remain charged even after the power has
been removed. High voltage can be present even when
the warning indicator lights are o. Failure to wait 20
minutes after power has been removed before
performing service or repair work can result in death or
serious injury.
1.Stop the motor.
2.Disconnect AC mains and remote DC-link
supplies, including battery back-ups, UPS, and
DC-link connections to other drives.
3.Disconnect or lock the PM motor.
4.Wait 20 minutes for the capacitors to discharge
fully before performing any service or repair
work.
Correct and reliable transport, storage, and installation are
required for the trouble-free and safe operation of the
VLT® Parallel Drive Modules. Only qualied personnel are
allowed to install this equipment.
Qualied personnel are dened as trained sta, who are
authorized to install 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 manual.
Safety Precautions
2.3
WARNING
HIGH VOLTAGE
The drive system contains high voltage when connected
to AC mains input. Failure to ensure that only qualied
personnel install the drive system can result in death or
serious injury.
WARNING
LEAKAGE CURRENT HAZARD (>3.5 mA)
Leakage currents exceed 3.5 mA. Failure to ground the
drive system properly can result in death or serious
injury. Follow national and local codes regarding
protective earthing of equipment with a leakage current
>3.5 mA. Frequency converter technology implies high
frequency switching at high power. This switching
generates a leakage current in the ground connection. A
fault current in the drive system at the output power
terminals sometimes contain a DC component, which can
charge the lter capacitors and cause a transient ground
current. The ground leakage current depends on various
system congurations including RFI ltering, shielded
motor cables, and drive system power.
If the leakage current exceeds 3.5 mA, EN/IEC 61800-5-1
(Power Drive System Product Standard) requires special
care.
Grounding must be reinforced in 1 of the following ways:
Ensure the correct grounding of the equipment
•
by a certied electrical installer.
Ground wire of at least 10 mm2 (6 AWG).
•
Two separate ground wires, both complying
•
with the dimensioning rules.
See EN 60364-5-54 § 543.7 for further information.
Frequency converters are designed in compliance with the
directives described in this section.
Table 3.1 Approvals
3.1 CE Mark
The CE mark (Communauté européenne) indicates that the
product manufacturer conforms to all applicable EU
directives. The EU directives applicable to the design and
manufacture of frequency converters are the Low Voltage
Directive, the EMC Directive, and (for units with an
integrated safety function) the Machinery Directive.
The CE mark is intended to eliminate technical barriers to
free trade between the EC and EFTA states inside the ECU.
The CE mark does not regulate the quality of the product.
Technical specications cannot be deduced from the CE
mark.
A frequency converter can be used as standalone device or
as part of a more complex installation. Devices used as
standalone or as part of a system must bear the CE mark.
Systems must not be CE marked but must comply with the
basic protection requirements of the EMC directive.
3.4 Machinery Directive
Frequency converters are
components subject to the Low Voltage Directive, however
frequency converters with an integrated safety function
must comply with the Machinery Directive 2006/42/EC.
Frequency converters without safety function do not fall
under the Machinery Directive. If a frequency converter is
integrated into machinery system, Danfoss provides
information on safety aspects relating to the frequency
converter.
Machinery Directive 2006/42/EC covers a machine
consisting of an aggregate of interconnected components
or devices of which at least 1 is capable of mechanical
movement. The directive mandates that the equipment
design must ensure the safety and health of people and
livestock are not endangered and the preservation of
material worth so long as the equipment is properly
installed, maintained, and used as intended.
classied as electronic
33
Low Voltage Directive
3.2
Frequency converters are classied as electronic
components and must be CE labeled in accordance with
the 2014/35/EU Low Voltage Directive. The directive
applies to all electrical equipment in the 50–1000 V AC
and the 75–1600 V DC voltage ranges.
The directive mandates that the equipment design must
ensure the safety and health of people and livestock are
not endangered and the preservation of material worth so
long as the equipment is properly installed, maintained,
and used as intended. Danfoss CE-labels comply with the
Low Voltage Directive and provide a declaration of
conformity on request.
EMC Directive
3.3
Electromagnetic compatibility (EMC) means that electromagnetic interference between apparatus does not hinder
their performance. The basic protection requirement of the
EMC Directive 2014/30/EU states that devices that generate
electromagnetic interference (EMI) or whose operation
could be aected 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.
When frequency converters are used in machines with at
least 1 moving part, the machine manufacturer must
provide declaration stating compliance with all relevant
statutes and safety measures. Danfoss CE-labels comply
with the Machinery Directive for frequency converters with
an integrated safety function and provide a declaration of
conformity on request.
UL Compliance
3.5
To ensure that the frequency converter meets the UL
safety requirements, see chapter 8.3 Electrical Requirementsfor Certications and Approvals.
RCM Mark Compliance
3.6
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 specied in
EN/IEC 61800-3 apply. A declaration of conformity can be
provided on request.
The drive system is designed by the installer to meet specied power requirements, using the VLT® Parallel Drive Modules
basic kit and any selected options kits. The basic kit consists of connecting hardware and either 2 or 4 drive modules, which
are connected in parallel.
The basic kit contains the following components:
Drive modules
•
Control shelf
44
•
Wire harnesses
•
-Ribbon cable with 44-pin connector (on both ends of the cable).
-Relay cable with 16-pin connector (on 1 end of the cable).
-DC fuse microswitch cable with 2-pin connectors (on 1 end of the cable).
DC fuses
•
Microswitches
•
Other components, such as busbar kits and back-channel cooling duct kits, are available as options to customize the drive
system.
The drive system in Illustration 4.4 shows a system using 4 drive modules. A system using 2 drive modules is similar, except
for the connecting hardware used. The illustrated drive system shows the cooling kit and the busbar option kit. However,
the installer can use other connection methods, including custom manufactured busbars or electrical cables.
NOTICE
The installer is responsible for the details of the drive system construction, including connections. Also, if the installer
does not use the Danfoss recommended design, the installer must obtain separate regulatory approvals.
Automatic energy optimization (AEO) is used in HVAC
applications. This feature directs the frequency converter to
monitor continuously the load on the motor and adjust
the output voltage to maximize eciency. Under light
load, the voltage is reduced and the motor current is
minimized. The motor benets from increased eciency,
reduced heating, and quieter operation. There is no need
to select a V/Hz curve because the frequency converter
automatically adjusts motor voltage.
5.1.2 Automatic Switching Frequency
Modulation
rate) causes noise in the motor, making a higher carrier
frequency preferable. A high carrier frequency, however,
generates heat in the frequency converter which can limit
the amount of current available to the motor. The use of
insulated gate bipolar transistors (IGBT) means high-speed
switching.
Automatic switching frequency modulation regulates these
conditions automatically to provide the highest carrier
frequency without overheating the frequency converter. By
providing a regulated high carrier frequency, it quiets
motor operating noise at slow speeds, when audible noise
control is critical, and produces full output power to the
motor when the demand requires.
5.1.3 Automatic Derating for High Carrier
Frequency
The frequency converter is designed for continuous and
full load operation between the carrier frequencies
between the minimum and maximum frequencies shown
in Table 5.1. If the carrier frequency is higher than the
maximum frequency, the output current of the frequency
converter is derated automatically.
55
The frequency converter generates short electrical pulses
to form an AC wave pattern. The carrier frequency is the
rate of these pulses. A low carrier frequency (slow pulsing
Power
kW (hp)
250 (350)3000200080003000
315 (450)2000150060002000
355 (500)2000150060002000
400 (550)2000150060002000
450 (600)2000150060002000
500 (650)2000150060002000
560 (750)2000150060002000
630 (900)2000150060002000
710 (1000)2000150060002000
800 (1200)2000150060002000
Table 5.1 Carrier Frequency Operational Ranges for 380–500 V
Table 5.2 Carrier Frequency Operational Ranges for 525–690 V
5.1.4 Automatic Derating for
Overtemperature
Automatic overtemperature derating works to prevent
tripping the frequency converter at high temperature.
Internal temperature sensors measure conditions to protect
the power components from overheating. The frequency
converter can automatically reduce its carrier frequency to
maintain its operating temperature within safe limits. After
reducing the carrier frequency, the frequency converter
can also reduce the output frequency and current by as
much as 30% to avoid an overtemperature trip.
Switching frequency
Hz
Minimum
Hz
nuisance trips. A short circuit between 2 output phases can
cause an overcurrent trip.
Maximum
Hz
Factory Setting
Hz
5.1.8 Ground Fault Protection
After receiving feedback from current sensors, the control
circuitry sums up the 3-phase currents from each drive
module. If the sum of all 3 output phase currents is not 0,
it indicates a leakage current. If the deviation from 0
exceeds a predetermined amount, the frequency converter
issues a ground fault alarm.
5.1.5 Auto Ramping
A motor trying to accelerate a load too quickly for the
current available can cause the frequency converter to trip.
The same is true for too quick of a deceleration. Auto
ramping protects against this scenario by extending the
motor ramping rate (acceleration or deceleration) to match
the available current.
5.1.6 Current Limit Control
If a load exceeds the current capability of the frequency
converter normal operation (from an undersized frequency
converter or motor), current limit reduces the output
frequency to slow the motor and reduce the load. An
adjustable timer is available to limit operation in this
condition for 60 s or less. The factory default limit is 110%
of the rated motor current to minimize overcurrent stress.
5.1.7 Short-circuit Protection
The frequency converter provides inherent short-circuit
protection with a fast acting fault-trip circuit. Current is
measured in each of the 3 output phases. After 5–10 ms, if
the current exceeds the permitted value, all transistors in
the inverter turn o. This circuit provides the most rapid
current sensing and the greatest protection against
5.1.9 Power Fluctuation Performance
The frequency converter withstands mains uctuations
such as
Transients.
•
Momentary dropouts.
•
Short voltage drops.
•
Surges.
•
The frequency converter automatically compensates for
input voltages ±10% from the nominal to provide full rated
motor voltage and torque. With auto restart selected, the
frequency converter automatically powers up after a
voltage trip. And with ying start, the frequency converter
synchronizes to motor rotation before starting.
5.1.10 Motor Soft Start
The frequency converter supplies the right amount of
current to the motor to overcome load inertia and bring
the motor up to speed. This action avoids full mains
voltage being applied to a stationary or slow turning
motor, which generates high current and heat. This
inherent soft start feature reduces thermal load and
mechanical stress, extends motor life, and provides quieter
system operation.
High-frequency motor resonance noise can be eliminated
by using resonance damping. Automatic or manually
selected frequency damping is available.
5.1.12 Temperature-controlled Fans
The internal cooling fans are temperature controlled by
sensors in the frequency converter. The cooling fan often is
not running during low-load operation, or when in sleep
mode or standby. This feature reduces noise, increases
eciency, and extends the operating life of the fan.
5.1.13 EMC Compliance
Electromagnetic interference (EMI) or radio frequency
interference (RFI) is disturbance that can aect an electrical
circuit due to electromagnetic induction or radiation from
an external source. The frequency converter is designed to
comply with the EMC product standard for IEC/EN 61800-3.
For more information regarding EMC performance, see
chapter 9.2 EMC Test Results.
The following functions are the most common functions
programmed for use in the frequency converter for
enhanced system performance. They require minimum
programming or set-up. Understanding that these
functions are available can optimize a system design and
possibly avoid introducing redundant components or
functionality. See the product-specicprogramming guide,
for instructions on activating these functions.
5.2.1 Automatic Motor Adaptation
frequency converter makes control decisions by comparing
the 2 signals to optimize system performance.
5.2.4 Automatic Restart
The frequency converter can be programmed to restart the
motor automatically after a minor trip, such as momentary
power loss or uctuation. This feature eliminates the need
for manual resetting and enhances automated operation
for remotely controlled systems. The number of restart
attempts and the duration between attempts can be
limited.
55
Automatic motor adaptation (AMA) is an automated test
procedure used to measure the electrical characteristics of
the motor. AMA provides an accurate electronic model of
the motor. It allows the frequency converter to calculate
optimal performance and eciency with the motor.
Running the AMA procedure also maximizes the automatic
energy optimization feature of the frequency converter.
AMA is performed without the motor rotating and without
uncoupling the load from the motor.
5.2.2 Motor Thermal Protection
5.2.5 Flying Start
Flying start allows the frequency converter to synchronize
with an operating motor rotating at up to full speed in
either direction. This feature prevents trips due to
overcurrent draw. It minimizes mechanical stress to the
system since the motor receives no abrupt change in
speed when the frequency converter starts.
5.2.6 Sleep Mode
Motor thermal protection can be provided in 2 ways.
One method uses a motor thermistor. The frequency
converter monitors motor temperature as the speed and
load vary to detect overheating conditions.
The other method calculates motor temperature by
measuring current, frequency, and operating time. The
frequency converter shows the thermal load on the motor
in percentage and can issue a warning at a programmable
overload setpoint. Programmable options at the overload
allow the frequency converter to stop the motor, reduce
output, or ignore the condition. Even at low speeds, the
frequency converter meets I2t Class 20 electronic motor
overload standards.
5.2.3 Built-in PID Controller
The built-in proportional, integral, derivative (PID)
controller is available, eliminating the need for auxiliary
control devices. The PID controller maintains constant
control of closed-loop systems where regulated pressure,
ow, temperature, or other system requirements must be
maintained. The frequency converter can provide selfreliant control the motor speed in response to feedback
signals from remote sensors.
Sleep mode automatically stops the motor when demand
is at a low level for a specied time. When the system
demand increases, the frequency converter restarts the
motor. Sleep mode provides energy savings and reduces
motor wear. Unlike a setback clock, the frequency
converter is always available to run when the preset wakeup demand is reached.
5.2.7 Run Permissive
The frequency converter can wait for a remote systemready signal before starting. When this feature is active, the
frequency converter remains stopped until receiving
permission to start. Run permissive ensures that the system
or auxiliary equipment is in the proper state before the
frequency converter is allowed to start the motor.
5.2.8 Full Torque at Reduced Speed
The frequency converter follows a variable V/Hz curve to
provide full motor torque even at reduced speeds. Full
output torque can coincide with the maximum designed
operating speed of the motor. This variable torque curve is
unlike variable torque converters that provide reduced
motor torque at low speed, or constant torque converters
that provide excess voltage, heat, and motor noise at less
than full speed.
The frequency converter accommodates 2 feedback signals
from 2 dierent devices. This feature allows regulating a
system with dierent feedback requirements. The
In some applications, the system can have operational
speeds that create a mechanical resonance. This
mechanical resonance can generate excessive noise and
possibly damage mechanical components in the system.
The frequency converter has 4 programmable bypassfrequency bandwidths. These bandwidths allow the motor
to step over speeds which induce system resonance.
5.2.10 Motor Preheat
To preheat a motor in a cold or damp environment, a small
amount of DC current can be trickled continuously into the
motor to protect it from condensation and a cold start.
This function can eliminate the need for a space heater.
5.2.11 4 Programmable Set-ups
The frequency converter has 4 set-ups which can be
independently programmed. Using multi-setup, it is
possible to switch between independently programmed
functions activated by digital inputs or a serial command.
Independent set-ups are used, for example, to change
references, or for day/night or summer/winter operation, or
to control multiple motors. The active set-up is shown on
the LCP.
Set-up data can be copied from frequency converter to
frequency converter by downloading the information from
the removable LCP.
5.2.15 Power Loss Ride-through
During a power loss, the frequency converter continues to
rotate the motor until the DC link voltage drops below the
minimum operating level, which corresponds to 15%
below the lowest rated drive voltage. Frequency converters
are rated for operation on 380–460 V, 550–600 V, and
some at 690 V. The power loss ride-through time depends
after the load on the frequency converter and the mains
voltage at the time of the power loss.
5.2.16 Overload
When the torque required to maintain or accelerate to a
determined frequency exceeds the current limit, the
frequency converter attempts to continue operating. It
automatically reduces the rate of acceleration or reduces
the output frequency. If the overcurrent demand is not
reduced enough, the frequency converter shuts down and
shows a fault within 1.5 s. The current limit level is
programmable. The overcurrent trip delay is used to
specify the time that the frequency converter operates in
current limit before shutting down. The limit level can be
set from 0–60 s, or for
frequency converter and motor thermal protection.
Safe Torque O (STO)
5.3
The VLT® AutomationDrive FC 302 comes standard with
Safe Torque O functionality via control terminal 37. The
STO function is also available on VLT® HVAC Drive FC 102
and VLT® AQUA Drive FC 202.
innite operation, subject to the
55
5.2.12 DC Braking
Some applications can require braking a motor to slow or
stop it. Applying DC current to the motor brakes the motor
and can eliminate the need for a separate motor brake.
The DC brake can be set to activate at a predetermined
frequency or after receiving a signal. The rate of braking
can also be programmed.
5.2.13 High Breakaway Torque
For high inertia or high friction loads, extra torque is
available for starting. The breakaway current of 110% or
160% of maximum can be set for a limited amount of
time.
5.2.14 Bypass
An automatic or manual bypass is an available option. The
bypass allows the motor to operate at full speed when the
frequency converter is not operating and allows for routine
maintenance or emergency bypass.
STO disables the control voltage of the power semiconductors of the frequency converter output stage, which in
turn prevents it from generating the voltage required to
rotate the motor. When the Safe Torque O (T37) is
activated, the frequency converter issues an alarm, trips
the unit, and coasts the motor to a stop. Manual restart is
required. The Safe Torque O function can be used for
stopping the frequency converter in emergency stop
situations. In the normal operating mode when Safe
Torque O is not required, use the regular stop function
instead. When automatic restart is used, the requirements
according to ISO 12100-2 paragraph 5.3.2.5 must be
fullled.
The Safe Torque O function with VLT® AutomationDrive
FC 302 can be used for asynchronous, synchronous, and
permanent magnet motors. It is possible that 2 faults occur
in the power semiconductors. If 2 faults in the power
semiconductors occur while using synchronous or
permanent magnet motors, it can cause a residual rotation
in the motor. The rotation can be calculated to angle=360/
(number of poles). The application using synchronous or
permanent magnet motors must take this possibility into
consideration and ensure that this scenario is not a critical
safety issue. This situation does not apply to asynchronous
motors.
5.3.1 Liability Conditions
The user is responsible for ensuring that personnel know
how to install and operate the Safe Torque O function by:
Reading and understanding the safety regulations
•
concerning health and safety/accident prevention.
Understanding the generic and safety guidelines
•
given in this description and the extended
®
55
description in the VLT
Frequency Converters –
Safe Torque O Operating Guide.
Having a good knowledge of the generic and
•
safety standards for the specic application.
The user is dened as integrator, operator, service, and
maintenance sta.
5.3.2 Additional Information
For more information regarding Safe Torque O, including
installation and commissioning, refer to the VLT® Frequency
Converters – Safe Torque O Operating Guide.
5.3.3 Installation of External Safety Device
If the ex-certied thermistor module MCB 112, which uses
terminal 37 as its safety-related switch-o channel, is
connected, then the output X44/12 of MCB 112 must be
AND-ed with a safety-related sensor (emergency stop key
or safety-guard switch) that activates Safe Torque O. The
output to Safe Torque O terminal 37 is high (24 V) only if
both the signal from MCB 112 output X44/12 and the
signal from the safety-related sensor are high. If at least 1
of the 2 signals are low, then the output to terminal 37
must be low, too. The safety device with this AND logic
itself must conform to IEC 61508, SIL 2. The connection
from the output of the safety device with safe AND logic
to Safe Torque O terminal 37 must be short circuit
protected. Illustration 5.1 shows a restart input for the
external safety device. In this installation, for example, set
[7] PTC 1 & Relay W or [8] PTC 1 & Relay A/W in
parameter 5-19 Terminal 37 Safe Stop. Refer to the VLT
Thermistor Card MCB 112 Operating Instructions for further
details.
in Combination with VLT® PTC
Thermistor Card MCB 112
®
PTC
Illustration 5.1 Illustration of the Essential Aspects for
Installing a Combination of a Safe Torque O Application and
an MCB 112 Application
Parameter settings for external safety device
with MCB 112
If MCB 112 is connected, then selections [4] through [9]
become possible for parameter 5-19 Terminal 37 Safe Stop
(Terminal 37 Safe Torque O).
Selections [1]* Safe Stop Alarm and [3] Safe Stop Warning in
parameter 5-19 Terminal 37 Safe Stop are still available, but
are used only for installations without MCB 112 or any
external safety devices. If [1]* Safe Stop Alarm or [3] SafeStop Warning in parameter 5-19 Terminal 37 Safe Stop is
selected by mistake and MCB 112 is triggered, then the
frequency converter reacts with alarm 72, Dangerous Failure
and coasts the frequency converter safely without an
automatic restart.
Selections [4] and [5] parameter 5-19 Terminal 37 Safe Stop
are only selected when MCB 112 uses the Safe Torque O.
If selections [4] PTC 1 Alarm or [5] PTC 1 Warning in
parameter 5-19 Terminal 37 Safe Stop is selected by mistake
and the external safety device triggers Safe Torque O, the
frequency converter reacts with alarm 72, Dangerous Failure
and coasts the frequency converter safely without an
automatic restart.
Selections [6] through [9] in parameter 5-19 Terminal 37Safe Stop must be selected for the combination of external
safety device and MCB 112.
[7] PTC 1 & Relay W and [8] PTC 1 & Relay A/W in
parameter 5-19 Terminal 37 Safe Stop opens up for
automatic restart when the external safety device is deactivated again.
The automatic restart is only allowed in the following
cases:
The unintended restart prevention is
•
implemented by other parts of the Safe Torque
O installation.
A presence in the dangerous zone can be
•
physically excluded when Safe Torque O is not
activated. In particular, paragraph 5.3.2.5 of ISO
12100-2 2003 must be observed.
See chapter 7.3.10 VLT® PTC Thermistor Card MCB 112 and
the VLT® PTC Thermistor Card MCB 112 Operating Guide for
more information about MCB 112.
5.4 System Monitoring
The frequency converter monitors many aspects of system
operation including:
Mains conditions.
•
Motor load and performance.
•
Frequency converter status.
•
An alarm or warning does not necessarily indicate a
problem with the frequency converter itself. It can be a
condition outside of the frequency converter that is being
monitored for performance limits. The frequency converter
has various preprogrammed fault, warning, and alarm
responses. Extra alarm and warning functions can be
selected to enhance or modify system performance.
5.4.3 High and Low Feedback Warning
In closed-loop operation, the frequency converter monitors
selected high and low feedback values. The display shows
a ashing high or ashing low warning when appropriate.
The frequency converter can also monitor feedback signals
in open-loop operation. While the signals do not aect the
operation of the frequency converter in open loop, they
can be useful for system status indication locally or via
serial communication. The frequency converter handles 39
dierent units of measure.
5.4.4 Imbalance of Supply Voltage or
Phase Loss
Excessive ripple current in the DC bus indicates either a
mains imbalance of supply voltage or phase loss. When a
power phase to the frequency converter is lost, the default
is to issue an alarm and trip the unit to protect the DC bus
capacitors. Other options are to issue a warning and to
reduce output current to 30% of full current, or to issue a
warning and continue normal operation. Operating a unit
connected to an imbalanced line can be desirable until the
imbalance is corrected.
5.4.5 High-frequency Warning
Useful in staging on extra equipment such as pumps or
cooling fans, the frequency converter can warn when the
motor speed is high. A specic high-frequency setting can
be entered into the frequency converter. When the output
of the unit exceeds the set warning frequency, the unit
shows a high-frequency warning. A digital output from the
frequency converter can signal external devices to turn on.
55
This section describes common alarm and warning
functions. Understanding that these functions are available
can optimize a system design and possibly avoid
introducing redundant components or functionality.
5.4.1 Operation at Overtemperature
By default, the frequency converter issues an alarm and
trips at overtemperature. If Autoderate and Warning are
selected, the frequency converter warns of the condition
but continues to run and attempts to cool itself by rst
reducing its carrier frequency. Then, if necessary, it reduces
the output frequency.
5.4.2 High and Low Reference Warning
In open-loop operation, the reference signal directly
determines the speed of the frequency converter. The
display shows a ashing reference high or low warning
when the programmed maximum or minimum is reached.
Useful in staging o equipment, the frequency converter
can warn when the motor speed is low. A specic lowfrequency setting can be selected for warning and to turn
o external devices. The unit does not issue a lowfrequency warning when it is stopped nor after start-up
until after the operating frequency has been reached.
5.4.7 High Current Warning
This function is similar to high-frequency warning (see
chapter 5.4.5 High-frequency Warning), except a high current
setting is used to issue a warning and turn on external
equipment. The function is not active when stopped or at
start-up until the set operating current has been reached.
Product Features
VLT® Parallel Drive Modules
5.4.8 Low Current Warning
This function is similar to low-frequency warning (see
chapter 5.4.6 Low-frequency Warning), except a low current
setting is used to issue a warning and turn o external
equipment. The function is not active when stopped or at
start up until the set operating current has been reached.
5.4.9 No Load/Broken Belt Warning
This feature can be used for monitoring a V-belt. After a
55
low current limit has been stored in the frequency
converter, if loss of the load is detected, the frequency
converter can be programmed to issue an alarm and trip
or to continue operation and issue a warning.
5.4.10 Lost Serial Interface
The frequency converter can detect loss of serial communication. A time delay of up to 18000 s is selectable to avoid
a response due to interruptions on the serial communications bus. When the delay is exceeded, available options
can:
Supply voltage
Supply frequency50/60 Hz ±5%
Maximum temporary imbalance between mains phases3.0% of rated supply voltage
True power factor (λ)≥0.98 nominal at rated load
Displacement power factor (cos Φ)(Approximately 1)
Switching on input supply L1, L2, L3Maximum 1 time per 2 minutes
Environment according to EN 60664-1Overvoltage category III/pollution degree 2
1) The unit is suitable for use on a circuit capable of delivering not more than 85000 RMS symmetrical Amperes, 480/600 V.
2) Mains voltage low/mains voltage drop-out:
During low mains voltage, the drive module continues until the DC-link voltage drops below the minimum stop level, which
corresponds typically to 15% below the lowest rated supply voltage. Power-up and full torque cannot be expected at mains
voltage lower than 10% below the lowest rated supply voltage. The drive module trips for a detected mains drop-out.
1)
2)
380–480, 500 V 690 V ±10%10%, 525–690 V ±10%
6.7 Motor Output and Motor Data
Motor output
Motor terminalsU/96, V/97, W/98
Output voltage0–100% of supply voltage
Output frequency0–590 Hz
Switching on outputUnlimited
Ramp times1–3600 s
6
6
Torque characteristics
Overload torque (constant torque)Maximum 150% for 60 s
Starting torqueMaximum 180% up to 0.5 s
Overload torque (variable torque)Maximum 110% for s
Starting torque (variable torque)Maximum 135% for s
1) Percentage relates to the nominal torque.
Eciency
Eciency
1) Eciency measured at nominal current. For energy eciency class, see chapter 6.9 Ambient Conditions for Drive Modules. For
part load losses, see www.danfoss.com/vltenergyeciency.
98%
6.8 12-Pulse Transformer Specications
ConnectionDy11 d0 or Dyn 11d0
Phase shift between secondaries30°
Voltage dierence between secondaries<0.5%
Short-circuit impedance of secondaries>5%
Short-circuit impedance dierence between secondaries<5% of short-circuit impedance
OtherNo grounding of the secondaries allowed. Static shield recommended
6.9 Ambient Conditions for Drive Modules
1)
1)
1)
1)
Environment
IP ratingIP00
Acoustic noise84 dB (running at full load)
Vibration test1.0 g
Vibration and shock (IEC 60721-33-3)Class 3M3
Maximum relative humidity5–95% (IEC 721–3–3; Class 3K3 (non-condensing)) during operation
Ambient temperature
Minimum ambient temperature during full-scale operation0 °C (32 °F)
Minimum ambient temperature at reduced performance-10 °C (14 °F)
Temperature during storage/transport-25 to +65 °C (-13 to 149 °F)
Maximum altitude above sea level without derating
EMC standards, EmissionEN 61800-3
EMC standards, ImmunityEN 61800-4-2, EN 61800-4-3, EN 61800-4-4, EN 61800-4-5, and EN 61800-4-6
Energy eciency class
1) Refer to chapter 6.12 Derating Specications for derating for high ambient temperature and derating for high altitude.
2) Determined according to EN 50598-2 at:
Rated load.
•
90% rated frequency.
•
Switching frequency factory setting.
•
Switching pattern factory setting.
•
1)
2)
VLT® Parallel Drive Modules
Maximum 45 °C (113 °F) (24-hour average maximum 40 °C (104 °F))
1)
1000 m (3281 ft)
IE2
6.10 Cable Specications
Cable lengths and cross-sections for control cables
Maximum motor cable length, shielded150 m (492 ft)
Maximum motor cable length, unshielded300 m (984 ft)
Maximum cross-section to control terminals, exible or rigid wire without cable end sleeves1.5 mm2/16 AWG
Maximum cross-section to control terminals, exible wire with cable end sleeves1 mm2/18 AWG
Maximum cross-section to control terminals, exible wire with cable end sleeves with collar0.5 mm2/20 AWG
Minimum cross-section to control terminals0.25 mm2/24 AWG
Maximum cross-section to 230 V terminals2.5 mm2/14 AWG
Minimum cross-section to 230 V terminals0.25 mm2/24 AWG
1) For power cables, see electrical data tables in chapter 6.5 Power-dependent Specications.
1)
6.11 Control Input/Output and Control Data
Digital inputs
Programmable digital inputs
Terminal number18, 19, 271), 291), 32, 33
LogicPNP or NPN
Voltage level0–24 V DC
Voltage level, logic 0 PNP<5 V DC
Voltage level, logic 1 PNP>10 V DC
Voltage level, logic 0 NPN
Voltage level, logic 1 NPN
Maximum voltage on input28 V DC
Pulse frequency range0–110 kHz
(Duty cycle) Minimum pulse width4.5 ms
Input resistance, R
All digital inputs are galvanically isolated from the supply voltage (PELV) and other high-voltage terminals.
1) Terminals 27 and 29 can also be programmed as output.
2) Except Safe Torque O input terminal 37.
2)
2)
i
Approximately 4 kΩ
4 (6)
>19 V DC
<14 V DC
1)
Safe Torque O (STO) Terminal 37
Voltage level0–24 V DC
Voltage level, logic 0 PNP<4 V DC
Voltage level, logic 1 PNP>20 V DC
Maximum voltage on input28 V DC
Typical input current at 24 V50 mA
Typical input current at 20 V60 mA
rms
rms
Input capacitance400 nF
All digital inputs are galvanically isolated from the supply voltage (PELV) and other high-voltage terminals.
1) See VLT® Frequency Converters – Safe Torque O Operating Guide for further information about terminal 37 and Safe Torque
O.
2) When using a contactor with a DC coil with STO, always make a return path for the current from the coil when turning it o.
The return path can be made by using a freewheel diode across the coil. Alternatively, use a 30 V or 50 V MOV for quicker
response time. Typical contactors can be bought with this diode.
Analog inputs
Number of analog inputs2
Terminal number53, 54
ModesVoltage or current
Mode selectSwitch S201 and switch S202
Voltage modeSwitch S201/switch S202 = OFF (U)
Voltage level-10 V to +10 V (scalable)
Input resistance, R
i
Approximately 10 kΩ
Maximum voltage±20 V
Current modeSwitch S201/switch S202 = ON (I)
Current level0/4–20 mA (scalable)
Input resistance, R
i
Approximately 200 Ω
Maximum current30 mA
Resolution for analog inputs10 bit (+ sign)
Accuracy of analog inputsMaximum error 0.5% of full scale
Bandwidth20 Hz/100 Hz
The analog inputs are galvanically isolated from the supply voltage (PELV) and other high-voltage terminals.
6
6
Illustration 6.18 PELV Isolation
Pulse input
Programmable pulse2/1
Terminal number pulse291), 32/33
Maximum frequency at terminal 29, 33110 kHz (Push-pull driven)
Maximum frequency at terminal 29, 335 kHz (open collector)
Minimum frequency at terminal 29, 334 Hz
Voltage level0–24 V DC
Maximum voltage on input28 V DC
Input resistance, R
i
Approximately 4 kΩ
Pulse input accuracy (0.1–1 kHz)Maximum error: 0.1% of full scale
Encoder input accuracy (1–11 kHz)Maximum error: 0.05% of full scale
The pulse and encoder inputs (terminals 29, 32, 33) are galvanically isolated from the supply voltage (PELV) and other highvoltage terminals.
Analog output
Number of programmable analog outputs1
Terminal number42
Current range at analog output0/4–20 mA
Maximum load GND - analog output500 Ω
Accuracy on analog outputMaximum error: 0.5% of full scale
Resolution on analog output12 bit
The analog output is galvanically isolated from the supply voltage (PELV) and other high-voltage terminals.
Control card, RS485 serial communication
Terminal number68 (P, TX+, RX+), 69 (N, TX-, RX-)
Terminal number 61Common for terminals 68 and 69
The RS485 serial communication circuit is functionally separated from other central circuits and galvanically isolated from the
supply voltage (PELV).
VLT® Parallel Drive Modules
6
Digital output
Programmable digital/pulse outputs2
Terminal number27, 29
Voltage level at digital/frequency output0–24 V
Maximum output current (sink or source)40 mA
Maximum load at frequency output1 kΩ
Maximum capacitive load at frequency output10 nF
Minimum output frequency at frequency output0 Hz
Maximum output frequency at frequency output32 kHz
Accuracy of frequency outputMaximum error: 0.1% of full scale
Resolution of frequency outputs12 bit
1) Terminals 27 and 29 can also be programmed as input.
The digital output is galvanically isolated from the supply voltage (PELV) and other high-voltage terminals.
Control card, 24 V DC output
Terminal number12, 13
Output voltage24 V +1, -3 V
Maximum load200 mA
The 24 V DC supply is galvanically isolated from the supply voltage (PELV), but has the same potential as the analog and digital
inputs and outputs.
Maximum terminal load (AC-1)1) on 4–5 (NO) (resistive load)
Maximum terminal load (AC-15)1) on 4–5 (NO) (inductive load @ cosφ 0.4)240 V AC, 0.2 A
Maximum terminal load (DC-1)1) on 4–5 (NO) (resistive load)80 V DC, 2 A
Maximum terminal load (DC-13)1) on 4–5 (NO) (inductive load)24 V DC, 0.1 A
Maximum terminal load (AC-1)1) on 4–6 (NC) (resistive load)240 V AC, 2 A
Maximum terminal load (AC-15)1) on 4–6 (NC) (inductive load @ cosφ 0.4)240 V AC, 0.2 A
Maximum terminal load (DC-1)1) on 4–6 (NC) (resistive load)50 V DC, 2 A
Maximum terminal load (DC-13)1) on 4–6 (NC) (inductive load)24 V DC, 0.1 A
Minimum terminal load on 1–3 (NC), 1–2 (NO), 4–6 (NC), 4–5 (NO)24 V DC 10 mA, 24 V AC 20 mA
Environment according to EN 60664-1Overvoltage category III/pollution degree 2
The relay contacts are galvanically isolated from the rest of the circuit by reinforced isolation (PELV).
2) Overvoltage Category II.
3) UL applications 300 V AC 2A.
Control card, 10 V DC output
Terminal number50
Output voltage10.5 V ±0.5 V
Maximum load25 mA
The 10 V DC supply is galvanically isolated from the supply voltage (PELV) and other high-voltage terminals.
Control characteristics
Resolution of output frequency at 0–590 Hz±0.003 Hz
Repeat accuracy of precise start/stop (terminals 18, 19)≤±0.1 ms
System response time (terminals 18, 19, 27, 29, 32, 33)≤10 ms
Speed control range (open loop)1:100 of synchronous speed
Speed control range (closed loop)1:1000 of synchronous speed
Speed accuracy (open loop)30–4000 RPM: error ±8 RPM
Speed accuracy (closed loop), depending on resolution of feedback device0–6000 RPM: error ±0.15 RPM
All control characteristics are based on a 4-pole asynchronous motor
Control card performance
Scan interval (VLT® HVAC Drive FC 102, VLT® Refrigeration Drive FC 103, VLT® AQUA
Drive FC 202)5 ms (VLT® AutomationDrive FC 302)
Scan interval (FC 302)1 ms
6
6
Control card, USB serial communication
USB standard1.1 (full speed)
USB plugUSB type B device plug
Connection to PC is carried out via a standard host/device USB cable.
The USB connection is galvanically isolated from the supply voltage (PELV) and other high-voltage terminals.
The USB ground connection is NOT galvanically isolated from protective earth. Use only an isolated laptop as PC connection to
the USB connector on the frequency converter.
) is the maximum temperature allowed. The average (T
AMB,MAX
) is measured over 24 hours
AMB,AVG
and must be at least 5 °C (41 °F) lower.
At 41.7 °C (107°F) , 100% of the rated output current is available. At 45 °C (113 °C ) (T
, MAX-3.3 K), 91% of the rated
AMB
output current is available.
NOTICE
FACTORY DERATING
The VLT® Parallel Drive Modules is already derated for operational temperature (55 °C (131 °F) T
(122 °F) T
AMB,AVG
).
6.12.3 Derating for Switching Frequency
Graphs are presented individually for 60° AVM and SFAVM. 60° AVM only switches 2/3 of the time, whereas SFAVM switches
throughout the whole period. The maximum switching frequency is 16 kHz for 60° AVM and 10 kHz for SFAVM.
Voltage
range
Switching
pattern
60 AVM
High overload HO, 150%Normal overload NO, 110%
AMB,MAX
and 50 °C
6
6
380–500 V
SFAVM
Table 6.16 Derating for Switching Frequency, 250 kW at 400 V AC (350 hp at 460 V AC)
Enclosure
Enclosure type
Enclosure class
Control supply voltage
Hardware conguration
RFI lter/Low Harmonic Drive/12-
pulse
Brake
Display (LCP)
Coating PCB
Mains option
Adaptation A
Adaptation B
Software release
Software language
A options
B options
C0 options, MCO
C1 options
C option software
D options
1–3
4–6
7
8–10
11
12
13–15
16–23
16–17
18
19
20
21
22
23
24–27
28
29–30
31–32
33–34
35
36–37
38–39
Not all choices/options are available for each variant. To
verify if the appropriate version is available, consult the
drive congurator on the Internet.
7.2 Drive Congurator
It is possible to design a frequency converter according to
the application requirements by using the ordering
number system shown in Table 7.1 and Table 7.2.
Order standard frequency converters and frequency
converters with integral options by sending a type code
string describing the product to the local Danfoss sales
oce, for example:
FC-302N800T5E00P2BGC7XXSXXXXAXBXCXXXXDX
The meaning of the characters in the string are
Table 7.3 and Table 7.4.
Match the appropriate drive for the proper application
using the drive congurator. The drive congurator
automatically generates an 8-digit sales number to be
delivered to the local sales oce. It is also possible to
establish a project list with several products and send it to
a Danfoss sales representative.
The drive congurator can be found on the global internet
site: www.danfoss.com/drives.
Frequency converters are delivered automatically with a
language package relevant to the region from which they
are ordered. Four regional language packages cover the
following languages:
Language Package 1
English, German, French, Danish, Dutch, Spanish, Swedish,
Italian, and Finnish.
dened in
Table 7.2 Type Code Example for Ordering a Frequency
The high-speed switching of the frequency converter produces some secondary eects that inuence the motor and the
enclosed environment. Two dierentlter types, the dU/dt and the sine-wave lters, are available to address these side
eects. For more detail, see VLT® FC-Series Output Filter Design Guide.
Galvanic Isolation in the VLT® General
Purpose I/O MCB 101
Danfoss oers a wide range of options and accessories for
the VLT® AutomationDrive FC 302. The following options
are installed on the control card in either slot A, slot B, or
slot C. Refer to Illustration 7.3. For further information, see
Digital/analog inputs are galvanically isolated from other
inputs/outputs on the MCB 101 and in the control card of
the frequency converter.
the instructions that accompany the optional equipment.
Digital/analog outputs in the MCB 101 are galvanically
isolated from other inputs/outputs on the MCB 101, but
not from the inputs/outputs on the control card of the
frequency converter.
Connect terminals 1 and 5 if the digital inputs 7, 8, or 9
are to be switched by use of the internal 24 V supply
(terminal 9). See Illustration 7.5.
77
1Slot A
2Slot B
3Slot C
Table 7.9
Illustration 7.3 Slot Options on the Control Card
VLT® General Purpose I/O MCB 101 is used for extension of
digital and analog inputs and outputs of FC 302. MCB 101
must be tted into slot B in the VLT® AutomationDrive FC
Digital Input
Number of digital inputs4 (6)
Terminal number18, 19, 27, 29, 32, 33
LogicPNP or NPN
Voltage level0–24 V DC
Voltage level, logic 0 PNP (GND=0 V)<5 V DC
Voltage level, logic 1 PNP (GND=0 V)>10 V DC
Voltage level, logic 0 NPN (GND=24 V)<14 V DC
Voltage level, logic 1 NPN (GND=24 V)>19 V DC
Maximum voltage on input28 V continuous
Pulse frequency range0–110 kHz
Duty cycle, minimum pulse width4.5 ms
Input impedance>2 kΩ
7.3.3 Analog Inputs - Terminal X30/11, 12
Analog Input
Number of analog inputs2
Terminal number53, 54, X30.11, X30.12
ModesVoltage
Voltage level-10 V to +10 V
Input impedance>10 kΩ
Maximum voltage20 V
Resolution for analog inputs10 bit (+ sign)
Accuracy of analog inputsMaximum error 0.5% of full scale
BandwidthVLT® AutomationDrive FC 302: 100 Hz
7.3.4 Digital Outputs - Terminal X30/6, 7
Digital Output
Number of digital outputs2
Terminal numberX30.6, X30.7
Voltage level at digital/frequency output0–24 V
Maximum output current40 mA
Maximum load≥600 Ω
Maximum capacitive load<10 nF
Minimum output frequency0 Hz
Maximum output frequency≤32 kHz
Accuracy of frequency outputMaximum error: 0.1% of full scale
77
7.3.5 Analog Output - Terminal X30/8
Analog Output
Number of analog outputs1
Terminal number42
Current range at analog output0–20 mA
Maximum load GND - analog output500 Ω
Accuracy on analog outputMaximum error: 0.5% of full scale
Resolution on analog output12 bit
The encoder module can be used as a feedback source for closed-loop ux control (parameter 1-02 Flux Motor Feedback
Source) and closed-loop speed control (parameter 7-00 Speed PID Feedback Source). Congure the encoder option in
parameter group 17-** Motor Feedback Option .
The Encoder Option MCB 102 is used for:
VVC+ closed loop.
•
Flux vector speed control.
•
Flux vector torque control.
•
Permanent magnet motor.
•
Supported encoder types:
Incremental encoder: 5 V TTL type, RS422, maximum frequency: 410 kHz.
•
Incremental encoder: 1Vpp, sine-cosine.
•
HIPERFACE® Encoder: Absolute and Sine-Cosine (Stegmann/SICK).
77
•
EnDat encoder: Absolute and Sine-Cosine (Heidenheim) Supports version 2.1.
•
SSI encoder: Absolute.
•
VLT® Parallel Drive Modules
NOTICE
The LEDs are only visible when removing the LCP. Reaction if there is an encoder error can be selected in
parameter 17-61 Feedback Signal Monitoring: [0] Disabled, [1] Warning, or [2] Trip.
When the encoder option kit is ordered separately, the kit includes:
VLT® Encoder Input MCB 102.
•
Enlarged LCP xture and enlarged terminal cover.
•
The encoder option does not support VLT® AutomationDrive FC 302 frequency converters manufactured before week
50/2004.
Minimum software version: 2.03 (parameter 15-43 Software Version)
Connector
Designation
X31
1NC
2NC8 VCC8 V Output (7–12 V, I
35 VCC5 VCC
4GNDGNDGNDGND
5A input+COS+COSA input
6A inv inputREFCOSREFCOSA inv input
7B input+SIN+SINB input
8B inv inputREFSINREFSINB inv input
9Z input+Data RS485Clock outClock outZ input OR +Data RS485
10Z inv input-Data RS485Clock out inv.Clock out inv.Z input OR -Data RS485
MCB 103 Resolver option is used for interfacing resolver
motor feedback to VLT® AutomationDrive FC 302. Resolvers
are used as motor feedback devices for permanent magnet
brushless synchronous motors.
When the resolver option is ordered separately, the kit
includes:
Resolver input option.MCB 103.
•
•
Enlarged LCP
xture and enlarged terminal cover.
Selection of parameters: 17-5* Resolver Interface.
MCB 103 Resolver Option supports a various number of
rotor resolver types.
77
Resolver polesParameter 17-50 Poles: 2 x 2
Resolver input
voltage
Resolver input
frequency
Transformation ratio Parameter 17-53 Transformation Ratio: 0.1–
Secondary input
voltage
Secondary load
Table 7.11 Resolver Specications
Parameter 17-51 Input Voltage: 2.0–8.0
7.0
Vrms
Vrms
x
Parameter 17-52 Input Frequency: 2–15 kHz
x 10.0 kHz
1.1 x 0.5
Maximum 4
Vrms
Illustration 7.9 Resolver Input MCB 103 used with a Permanent
Magnet Motor
Approximately 10 kΩ
NOTICE
The MCB 103 can be used with only rotor-supplied
resolver types. Stator-supplied resolvers cannot be used.
LED indicators
The LEDs are active when parameter 17-61 Feedback Signal
Monitoring is set to [1] Warning or [2] Trip.
LED 1 is on when the reference signal is OK to resolver.
LED 2 is on when Cosinus signal is OK from resolver.
LED 3 is on when Sinus signal is OK from resolver.
Illustration 7.10 Permanent Magnet (PM) Motor with Resolver
as Speed Feedback
Set-up example
In Illustration 7.9, a permanent magnet (PM) Motor is used
with resolver as speed feedback. A PM motor must usually
operate in ux mode.
Wiring
The maximum cable length is 150 m (492 ft) when a
twisted-pair type of cable is used.
NOTICE
Always use shielded motor cables and brake chopper
cables. Resolver cables must be shielded and separated
from the motor cables. The shield of the resolver cable
must be correctly connected to the decoupling plate and
connected to chassis (ground) on the motor side.
Illustration 7.13 Correct Method to Install Live Parts and
Control Signals
130BF022.10
Ordering InformationDesign Guide
7.3.9
VLT® 24 V DC Supply MCB 107
A 24 V DC external supply can be installed for low-voltage supply to the control card and any installed options card,
enabling full operation of the LCP without connection to the mains.
24 V DC external supply specication
Input voltage range24 V DC ±15% (maximum 37 V in 10 s)
Maximum input current2.2 A
Average input current for FC 3020.9 A
Maximum cable length75 m (246 ft)
Input capacitance load10 uF
Power-up delay0.6 s
The inputs are protected.
Terminal numbers:
Terminal 35: - 24 V DC external supply.
•
Terminal 36: + 24 V DC external supply.
•
When VLT® 24 V DC Supply MCB 107 is supplying the
control circuit, the internal 24 V supply is automatically
disconnected. For more information on installation, consult
the separate instructions that accompany the optional
equipment.
The MCB 112 option makes it possible to monitor the
temperature of an electrical motor through a galvanically
isolated PTC thermistor input. It is a B-option for VLT
AutomationDrive FC 302 with Safe Torque O (STO).
VLT® PTC Thermistor Card MCB 112
®
ATEX Certication with VLT® AutomationDrive FC 302
The VLT® PTC Thermistor Card MCB 112 has been certied
for ATEX, which means that the FC 302 together with the
MCB 112 can now be used with motors in potentially
explosive atmospheres. See the thermistor card for more
For information on mounting and installing the option, see
information.
the instructions that accompany it. For dierent application
possibilities, see chapter 17 Application Examples.
X44/1 and X44/2 are the thermistor inputs. X44/12 enables
Safe Torque O of the FC 302 (T-37) if the thermistor
values make it necessary, and X44/10 informs the FC 302
that a request for Safe Torque O has come from the MCB
112 to ensure suitable alarm handling. To use the
Illustration 7.16 ATmosphère EXplosive (ATEX) Symbol
information from X44/10, 1 of the digital inputs of the
77
VLT® AutomationDrive FC 302 (or a DI of a mounted
option) must be set to PTC Card 1 [80].
Parameter 5-19 Terminal 37 Safe Stop must be congured to
the desired Safe Torque O functionality. Default is [1] SafeStop Alarm.
Resistor Connection
PTC compliant with DIN 44081 and DIN 44082
Number1..6 resistors in series
Shut-o value3.3 Ω.... 3.65 Ω ... 3.85 Ω
Reset value1.7 Ω .... 1.8 Ω ... 1.95 Ω
Trigger tolerance± 6 °C
Collective resistance of the sensor loop<1.65 Ω
Terminal voltage≤ 2.5 V for R ≤3.65 Ω, ≤9 V for R=∞
Sensor current≤ 1 mA
Short circuit20 Ω≤R ≤40 Ω
Power consumption60 mA
Testing Conditions
EN 60 947-8
Measurement voltage surge resistance6000 V
Overvoltage categoryIII
Pollution degree2
Measurement isolation voltage Vbis690 V
Galvanic isolation until Vi500 V
Permanent ambient temperature-20 °C (-4 °F)... +60 °C (140 °F)
EN 60068-2-1 Dry heat
Moisture5–95%, no condensation allowed
EMC resistanceEN 61000-6-2
EMC emissionsEN 61000-6-4
Vibration resistance10 ... 1000 Hz 1.14 g
Shock resistance50 g
77
Safety System Values
EN 61508 for Tu=75 °C (167 °F) ongoing
SIL2 for maintenance cycle of 2 years
Ensure galvanic isolation between the VLT® AutomationDrive and the option card MCB 113 by connecting to
The MCB 113 adds 7 digital inputs, 2 analog outputs, and
4 SPDT relays to the standard I/O of the frequency
converter, providing increased exibility and compliance
an external 24 V on X58/. If galvanic isolation is not
needed, the option card can be powered through internal
24 V from the frequency converter.
with the German NAMUR NE37 recommendations.
The MCB 113 is a standard C1-option for the Danfoss VLT
AutomationDrive FC 302 and is detected automatically
after mounting.
®
NOTICE
It is acceptable to combine 24 V signals with highvoltage signals in the relays as long as there is 1 unused
relay in-between.
To set up MCB 113, use parameter groups 5-1* Digital
Inputs, 6-7* Analog Output 3, 6-8* Analog Output 4, 14-8*
Options, 5-4* Relays, and 16-6* Inputs and Outputs.
NOTICE
In parameter group 5-4* Relays, array [2] is relay 3, array
77
Illustration 7.17 Electrical Connections of MCB 113
Electrical data
[3] is relay 4, array [4] is relay 5, and array [5] is relay 6.
Relays
Numbers4 SPDT
Load at 250 V AC/30 V DC8A
Load at 250 V AC/30 V DC with cosφ = 0.43.5 A
Overvoltage category (contact-earth)III
Overvoltage category (contact-contact)II
Combination of 250 V and 24 V signalsPossible with 1 unused relay in between
Maximum thru-put delay10 ms
Isolated from ground/ chassis for use on IT mains systems
Digital Inputs
Numbers7
Range0/24 V
ModePNP/NPN
Input impedance4 kW
Low trigger level6.4 V
High trigger level17 V
Maximum through-put delay10 ms
Analog Outputs
Numbers2
Range0/4-20 mA
Resolution11 bit
Linearity<0.2%
EMC
EMCIEC 61000-6-2 and IEC 61800-3 regarding Immunity of BURST, ESD, SURGE, and Conducted Immunity
Brake resistors are used to dissipate the excess energy
from the regenerative braking. The resistor is selected in
respect to its ohmic value, its power dissipation rate, and
its physical size. Danfoss oers a wide variety of dierent
resistors that are specially designed to our frequency
converters. For more information, see
chapter 13.2.1 Selection of Brake Resistor. Also, see the VLT
Brake Resistor MCE 101 Design Guide.
7.3.13 Sine-wave Filters
When a frequency converter controls a motor, resonance
noise is heard from the motor. This noise, which results
from the motor design, occurs every time an inverter
switch in the frequency converter is activated. The
frequency of the resonance noise thus corresponds to the
switching frequency of the frequency converter.
For the frequency converter, Danfoss can supply a sine-
lter to dampen the acoustic motor noise. The lter
wave
reduces the ramp-up time of the voltage, the peak load
voltage U
lter results in the current and voltage becoming almost
sinusoidal, which reduces the acoustic motor noise.
, and the ripple current ΔI to the motor. The
PEAK
7.3.14 dU/dt Filters
The combination of rapid voltage and an increase in
current stresses the motor insulation. These rapid energy
uctuations can be reected back to the DC-line in the
inverter, which can cause a shutdown. The dU/dt lter is
designed to reduce the voltage rise time and the rapid
energy change in the motor. This intervention avoids
®
premature aging and ashover in the motor insulation.
The dU/dt
of magnetic noise in the cable that connects the frequency
converter to the motor. The voltage wave form is still pulse
shaped, but the dU/dt ratio is reduced in comparison to an
installation without a lter.
lters have a positive inuence on the radiation
77
The ripple current in the sine-wave lter coils also causes
some noise. This problem can be solved integrating the
lter in a cabinet or similar enclosure.
For specic sine-wave lter part numbers, see
chapter 7.2.1 Output Filters.
The LCP can be moved to the front of a cabinet by using
the remote built-in kit. Also available is an LCP Kit without
LCP. For IP66 units, the ordering number is 130B1117. Use
ordering number 130B1129 for IP55 units.
EnclosureIP54 front
Maximum cable length between the LCP and
the unit3 m (9 ft. 10 in)
Communication standardRS485
Table 7.13 Technical Data for Mounting an LCP to the IP66
Enclosure
Illustration 7.19 Ordering Number 130B1113, LCP Kit with
Graphical LCP, Fasteners, Cable, and Gasket
77
Illustration 7.18 Dimensions
Illustration 7.20 Ordering Number 130B1114, LCP Kit with
Table 7.14 provides a checklist for integrating a frequency converter into a motor control system. The list is intended as a
reminder of the general categories and options necessary for specifying the system requirements.
For specications regarding ambient conditions, see
chapter 6.9 Ambient Conditions for Drive Modules.
NOTICE
CONDENSATION
Moisture can condense on the electronic components
and cause short circuits. Avoid installation in areas
subject to frost. Install a cabinet heater when the unit is
colder than the ambient air. Operating in stand-by mode
reduces the risk of condensation as long as the power
dissipation keeps the circuitry free of moisture.
Aggressive gases, such as hydrogen sulphide, chlorine, or
ammonia can damage the electrical and mechanical
components. The VLT® Parallel Drive Modules uses
conformal-coated circuit boards to reduce the eects of
aggressive gases. For conformal-coating class specications
and ratings, see chapter 6.9 Ambient Conditions for DriveModules.
When installing the unit in dusty environments, pay
attention to the following:
Periodic maintenance
When dust accumulates on electronic components, it acts
as a layer of insulation. This layer reduces the cooling
capacity of the components, and the components become
warmer. The hotter environment decreases the life of the
electronic components.
Keep the heat sink and fans free from dust build-up. For
more service and maintenance information, refer to VLTParallel Drive Modules Service Manual.
Cooling fans
Fans provide airow to cool the unit. When fans are
exposed to dusty environments, the dust can damage the
fan bearings and cause premature fan failure.
®
Class d species that if a spark occurs, it is
•
contained in a protected area.
Class e prohibits any occurrence of a spark.
•
Motors with class d protection
Does not require approval. Special wiring and containment
are required.
Motors with class e protection
When combined with an ATEX approved PTC monitoring
device like the VLT® PTC Thermistor Card MCB 112, installation does not need an individual approval from an
approbated organization.
Motors with class d/e protection
The motor itself has an e ignition protection class, while
the motor cabling and connection environment is in
compliance with the d classication. To attenuate the high
peak voltage, use a sine-wave
Drive Modules output.
When using the VLT® Parallel Drive Modules in a
potentially explosive atmosphere, use the following:
Motors with ignition protection class d or e.
•
PTC temperature sensor to monitor the motor
•
temperature.
Short motor cables.
•
Sine-wave output lters when shielded motor
•
cables are not used.
lter at the VLT® Parallel
NOTICE
MOTOR THERMISTOR SENSOR MONITORING
VLT® AutomationDrive units with the MCB 112 option are
PTB-certied for potentially explosive atmospheres.
A frequency converter contains many mechanical and
electronic components, many of which are vulnerable to
environmental eects.
88
WARNING
EXPLOSIVE ATMOSPHERE
Do not install the frequency converter in a potentially
explosive atmosphere. Install the unit in a cabinet
outside of this area. Failure to follow this guideline
increases risk of death or serious injury.
Systems operated in potentially explosive atmospheres
must fulll special conditions. EU Directive 94/9/EC (ATEX
95) classies the operation of electronic devices in
potentially explosive atmospheres.
The frequency converter should not be installed in
environments with airborne liquids, particles, or gases
capable of aecting and damaging the electronic
components. Failure to take the necessary protective
measures increases the risk of stoppages, thus reducing
the life of the frequency converter.
Degree of protection as per IEC 60529
To prevent cross faults and short circuits between
terminals, connectors, tracks, and safety-related circuitry
caused by foreign objects, the Safe Torque O (STO)
function must be installed and operated in an IP54 or
higher rated control cabinet (or equivalent environment).
Considerations During Insta...
VLT® Parallel Drive Modules
Liquids can be carried through the air and condense in the
frequency converter and can cause corrosion of
components and metal parts. Steam, oil, and salt water can
cause corrosion of components and metal parts. In such
environments, use equipment with enclosure rating IP
54/55. As an extra protection, coated printed circuit boards
can be ordered as an option.
Airborne particles such as dust can cause mechanical,
electrical, or thermal failure in the frequency converter. A
typical indicator of excessive levels of airborne particles is
dust particles around the frequency converter fan. In dusty
environments, use equipment with enclosure rating IP54/
IP55.
In environments with high temperatures and humidity,
corrosive gases such as sulphur, nitrogen, and chlorine
compounds cause chemical reactions on the frequency
converter components.
Such chemical reactions rapidly aect and damage the
electronic components. In such environments, mount the
equipment in a cabinet with fresh air ventilation, keeping
88
aggressive gases away from the frequency converter.
Optional coated PCBs also oer protection in such
environments.
Ventilation openingsSee chapter 8.2.4 Cooling and Airow
Table 8.1 Cabinet Requirements
1) Required if Danfoss busbar or cooling kits are used.
2000 (78.7)
2-drive: 450 (992), 4-drive: 910 (2006)
Requirements.
1)
8.2.2 Busbars
If the Danfoss busbar kit is not used, see Table 8.2 for the
cross-section measurements that are required when
creating customized busbars. For terminal dimensions, refer
to chapter 6.1.2 Terminal Dimensions and chapter 6.1.3 DCBus Dimensions.
DescriptionWidth [mm (in)]Thickness [mm (in)]
AC motor143.6 (5.7)6.4 (0.25)
AC mains143.6 (5.7)6.4 (0.25)
DC bus76.2 (3.0)12.7 (0.50)
NOTICE
Mounting frequency converters in aggressive
environments increases the risk of stoppages and considerably reduces the life of the frequency converter.
Before installing the frequency converter, check the
ambient air for liquids, particles, and gases by observing
existing installations in the environment. Typical indicators
of harmful airborne liquids are water or oil on metal parts,
or corrosion of metal parts.
Excessive dust particle levels are often found on installation cabinets and existing electrical installations. One
indicator of aggressive airborne gases is blackening of
copper rails and cable ends.
Minimum System Requirements
8.2
8.2.1 Cabinet
The kit consists of either 2 or 4 drive modules, depending
on the power rating. The cabinets have to meet the
following minimum requirements:
Table 8.2 Cross-section Measurements for Customized Busbars
NOTICE
Align busbars vertically to provide maximum airow.
8.2.3 Thermal Considerations
For heat dissipation values, refer to chapter 6.5 Power-dependent Specications. The following heat sources must
be considered when determining cooling requirements:
Ambient temperature outside enclosure.
•
Filters (for example, sine-wave and RF).
•
Fuses.
•
Control components.
•
For required cooling air, refer to chapter 8.2.4 Cooling andAirow Requirements.
The recommendations provided in this section are necessary for eective cooling of the drive modules within the panel
enclosure. Each drive module contains a heat sink fan and a mixing fan. Typical enclosure designs utilize door fans along
with the drive module fans to remove waste heat from the enclosure.
Danfoss provides several back-channel cooling kits as options. These kits remove 85% of the waste heat from the enclosure,
reducing the need for large door fans.
NOTICE
Make sure that the total ow of the cabinet fans meets the recommended airow.
Drive module cooling fans
The drive module is equipped with a heat sink fan, which provides the required
heat sink. Also, there is a cooling fan mounted on the top of the unit, and a small 24 V DC mixing fan mounted under the
input plate that operates any time the drive module is powered on.
In each drive module, the power card provides DC voltage to power the fans. The mixing fan is powered by 24 V DC from
the main switch mode power supply. The heat sink fan and the top fan are powered by 48 V DC from a dedicated switch
mode power supply on the power card. Each fan has a tachometer feedback to the control card to conrm that the fan is
operating correctly. On/o and speed control of the fans help reduce unnecessary acoustical noise and extend the life of the
fans.
Cabinet fans
When the back-channel option is not used, fans mounted in the cabinet must remove all the heat generated inside the
enclosure.
For each enclosure housing 2 drive module, the cabinet fan ow recommendation is as follows:
When back-channel cooling is used, 680 m3/h (400 cfm) ow is recommended.
•
ow rate of 840 m3/h (500 cfm) across the
88
When back-channel cooling is not used, 4080 m3/h (2400 cfm) ow is recommended.
•
Illustration 8.1 Airow, Standard Unit (Left), Bottom/Top Cooling Kit (Middle), and Back/Back Cooling Kit (Right)
8.3 Electrical Requirements for Certications and Approvals
The standard conguration provided in this guide (drive modules, control shelf, wire harnesses, fuses, and microswitches) is
UL and CE certied. The following conditions must be met apart from the standard conguration to obtain UL and CE
regulatory approval requirements. For a list of disclaimers, see chapter 18.1 Disclaimer.
Use the frequency converter in a heated, indoor-controlled environment. Cooling air must be clean, free from
•
corrosive materials, and electrically conductive dust. See chapter 6.9 Ambient Conditions for Drive Modules for
specic limits.
Maximum ambient air temperature is 40 °C (104 °F) at rated current.
•
The drive system must be assembled in clean air, according to enclosure classication. To obtain UL or CE certi-
•
cation regulatory approvals, drive modules must be installed according to the standard conguration provided in
this guide.
Maximum voltage and current must not exceed the values provided in for the specied drive conguration.
•
The drive modules are suitable for use on a circuit capable of delivering not more than 100 kA rms symmetrical
•
amperes at the drive nominal voltage (600 V maximum for 690 V units) when protected by fuses with the standard
conguration. Refer to chapter 8.4.1 Fuse Selection. The ampere rating is based on tests done according to UL 508C.
The cables located within the motor circuit must be rated for at least 75 °C (167 °F) in UL-compliant installations.
•
The cable sizes have been provided in for the specied drive conguration.
88
The input cable must be protected with fuses. Circuit breakers must not be used without fuses in the U.S. Suitable
•
IEC (class aR) fuses and UL (class L or T ) fuses are listed in chapter 8.4.1 Fuse Selection. In addition, country-specic
regulatory requirements must be adhered to.
For installation in the U.S., branch circuit protection must be provided according to the National Electrical Code
•
(NEC) and any applicable local codes. To fulll this requirement, use UL-classied fuses.
For installation in Canada, branch circuit protection must be provided according to the Canadian Electrical Code
•
and any applicable provincial codes. To fulll this requirement, use the UL-classied fuses.
To protect the drive system in case 1 or more internal components break down within a drive module, use fuses and/or
circuit breakers at the mains supply side.
8.4.1.1 Branch Circuit Protection
To protect the installation against electrical and re hazards, protect all branch circuits in an installation against short circuit
and overcurrent according to national and international regulations.
8.4.1.2 Short-circuit Protection
Danfoss recommends the fuses listed in chapter 8.4.1.3 Recommended Fuses for CE Compliance and
chapter 8.4.1.4 Recommended Fuses for UL Compliance to achieve CE or UL Compliance in the protection of service personnel
and property against the consequences of component breakdown in the drive modules.
Electrical interference is most commonly found at frequencies in the range 150 kHz to 30 MHz. Airborne interference from
the frequency converter system in the range 30 MHz to 1 GHz is generated from the inverter, motor cable, and the motor.
Capacitive currents in the motor cable coupled with a high dU/dt from the motor voltage generate leakage currents.
Shielded motor cables increase the leakage current (see Illustration 9.1) because they have higher capacitance to ground
than unshielded cables. If the leakage current is not ltered, it causes greater interference on the mains in the radio
frequency range below 5 MHz. Since the leakage current (I1) is carried back to the unit through the shield (I 3), there is only
a small electromagnetic eld (I4) from the shielded motor cable.
While the shield reduces the radiated interference, it increases the low-frequency interference on the mains. Connect the
motor cable shield to the frequency converter enclosure and to the motor enclosure. To connect the shield, use integrated
shield clamps to avoid twisted shield ends. The twisted shield ends increase the shield impedance at higher frequencies,
which reduces the shield eect and increases the leakage current (I4).
If a shielded cable is used for eldbus, relay, control cable, signal interface, or brake, mount the shield on the enclosure at
both ends. In some situations, however, it is necessary to break the shield to avoid current loops.
1Ground wire
2Shield
3AC mains supply
4Frequency converter
5Shielded motor cable
6Motor
Illustration 9.1 Leakage Currents
Illustration 9.1 shows an example of a 6-pulse frequency converter, but could be applicable to a 12-pulse as well.
If placing the shield on a mounting plate, use a metal plate because the shield currents must be conveyed back to the
frequency converter. Ensure good electrical contact from the mounting plate through the mounting screws to the frequency
converter chassis. When unshielded cables are used, some emission requirements are not complied with, although the
immunity requirements are observed.
To reduce the interference level from the entire system (unit and installation), make motor and brake cables as short as
possible. Avoid placing cables with a sensitive signal level alongside motor and brake cables. Radio interference higher than
50 MHz (airborne) comes from the control electronics. For more information on EMC, see chapter 9.5 EMC Recommendations.
VLT® Parallel Drive Modules
9.2 EMC Test Results
The following test results have been obtained using a frequency converter (with options if relevant), a shielded control
cable, a control box with potentiometer, motor shielded cables, and a motor.
RFI lter typeConducted emissionRadiated Emission
Standards and
requirements
P2, P4 (FC 302)No150 mNoYes
P6, P8 (FC 302)150 m (492 ft)150 m (492 ft)YesYes
Table 9.1 EMC Test Results (Emission and Immunity)
This type of power drive system is not intended to be used on a low-voltage public network that supplies domestic
premises. Radio frequency interference is expected if used on such a network, and supplementary mitigation measures
may be required.
The frequency converter meets the emission requirement for C3 category with 150 m (492 ft) shielded cable. In order to
meet the C2 category requirement, an external RFI lter is required.
Illustration 9.2 shows the electrical diagram of the RFI lter that was used to qualify the frequency converter. In this scenario,
the RFI lter is isolated from the ground, and the RFI relay is disabled using parameter 14-50 RFI Filter.
According to the EMC product standard for frequency converters EN/IEC 61800-3, the EMC requirements depend on the
environment in which the frequency converter is installed. These environments along with the mains voltage supply
requirements are dened in Table 9.3.
CategoryDenition
C1Frequency converters installed in a home and oce environment with a supply
voltage less than 1000 V.
C2Frequency converters installed in the home and oce environment with a supply
voltage less than 1000 V. These frequency converters are not plug-in and cannot be
moved and are intended to for professional installation and commissioning.
C3Frequency converters installed in an industrial environment with a supply voltage
lower than 1000 V.
C4Frequency converters installed in an industrial environment with a supply voltage
equal to or above 1000 V or rated current equal to or above 400 A or intended for
use in complex systems.
Table 9.3 Emission Requirements
Conducted emission requirement
according to EN 55011 limits
Class B
Class A Group 1
Class A Group 2
No limit line
Make an EMC plan
When the generic emission standards are used, the frequency converters are required to comply with Table 9.4
EnvironmentGeneric standard
First environment
(home and oce)
Second environment
(industrial environment)
Table 9.4 Generic Emission Standard Limits
EN/IEC 61000-6-3 Emission standard for residential, commercial,
and light industrial environments.
EN/IEC 61000-6-4 Emission standard for industrial environments.Class A Group 1
The immunity requirements for frequency converters depend on the environment where they are installed. The
requirements for the industrial environment are higher than the requirements for the home and oce environment. All
Danfoss frequency converters comply with the requirements for both the industrial and the home/oce environment.
To document immunity against electrical interference, the following immunity tests have been performed on a frequency
converter (with options if relevant), a shielded control cable and a control box with potentiometer, motor cable, and motor.
The tests were performed in accordance with the following basic standards. For more details, see Table 9.5.
EN/IEC 61000-4-2: Electrostatic discharges (ESD): Simulation of electrostatic discharges from human beings.
•
EN/IEC 61000-4-3: Incoming electromagnetic
•
radar and radio communication equipment, as well as mobile communications equipment.
EN/IEC 61000-4-4: Burst transients: Simulation of interference brought about by switching a contactor, relay, or
•
similar devices.
EN/IEC 61000-4-5: Surge transients: Simulation of transients brought about by lightning strikes near installations.
•
EN/IEC 61000-4-6: RF common mode: Simulation of the eect from radio-transmission equipment joined by
•
connection cables.
eld radiation, amplitude modulated simulation of the eects of
Basic standardBurst
IEC 61000-4-4
99
Acceptance criterionBBBAA
Line
Motor
Brake4 kV CM
Load sharing4 kV CM
Control wires
Standard bus2 kV CM
Relay wires2 kV CM
Application and Fieldbus
options
LCP cable
External 24 V DC
Enclosure
Table 9.5 EMC Immunity Form, Voltage Range: 380–500 V, 525–600 V, 525–690 V
1) Injection on cable shield.
AD: Air Discharge; CD: Contact Discharge; CM: Common mode; DM:
The following is a guideline to good engineering practice when installing frequency converters. Follow these guidelines in
compliance with EN/IEC 61800-3 First environment. If the installation is in EN/IEC 61800-3 Second environment, industrial
networks, or in an installation with its own transformer, deviation from these guidelines is allowed but not recommended.
Good engineering practice to ensure EMC-correct electrical installation:
Use only braided shielded/armored motor cables and braided shielded control cables. The shield provides a
•
minimum coverage of 80%. The shield material must be metal, not limited to but typically copper, aluminum, steel,
or lead. There are no special requirements for the mains cable.
Installations using rigid metal conduits are not required to use shielded cable, but the motor cable must be
•
installed in conduit separate from the control and mains cables. Full connection of the conduit from the frequency
converter to the motor is required. The EMC performance of
manufacturer must be obtained.
Connect the shield conduit to ground at both ends for motor cables and for control cables. Sometimes, it is not
•
possible to connect the shield in both ends. If so, connect the shield at the frequency converter. See also
chapter 9.5.2 Grounding of Shielded Control Cables.
Avoid terminating the shield with twisted ends (pigtails). It increases the high frequency impedance of the shield,
•
which reduces its eectiveness at high frequencies. Use low impedance cable clamps or EMC cable glands instead.
Avoid using unshielded motor or control cables inside cabinets housing the frequency converter, whenever
•
possible.
exible conduits varies a lot and information from the
Leave the shield as close to the connectors as possible.
Illustration 9.7 shows an example of an EMC-correct electrical installation of an IP20 frequency converter. The frequency
converter is tted in an installation cabinet with an output contactor and connected to a PLC, which is installed in a
separate cabinet. Other ways of doing the installation could have just as good an EMC performance, provided the guidelines
to engineering practice are followed.
If the installation is not carried out according to the guideline, and if unshielded cables and control wires are used, some
emission requirements are not in compliance, although the immunity requirements are fullled.
Minimum 200 mm
between control
cables, motor cable,
and mains cable
Motor, 3-phases and protective ground
PLC, etc.Panel
Output contactor, etc.
Ground rail
Cable insulation stripped
All cable entries in 1 side of panel
130BA048.14
EMC and Harmonics
VLT® Parallel Drive Modules
99
Illustration 9.7 EMC-correct Electrical Installation of a Frequency Converter in Cabinet
9.5.1 Using Shielded Control Cables
Danfoss recommends braided shielded/armored cables to optimize EMC immunity of the control cables and the EMC
emission from the motor cables.
The ability of a cable to reduce the incoming and outgoing radiation of electric noise depends on the transfer impedance
(ZT). The shield of a cable is normally designed to reduce the transfer of electric noise. However, a shield with a lower
transfer impedance (ZT) value is more eective than a shield with a higher transfer impedance (ZT).