VLT
®
FCD Series
■ Technology
■ Control principle
A frequency converter rectifies AC voltage from the
mains supply into DC voltage, following which it
changes this voltage to an AC voltage with variable
amplitude and frequency.
The motor thus receives a variable voltage and fre-
quency, which enables infinitely variable speed
control of three-phase, standard AC motors.
1. Mains voltage
3 x 380 - 480 V AC, 50 / 60 Hz.
2
. Rectifier
Three-phase rectifier bridge which rectifies AC volt-
age into DC voltage.
3
. Intermediate circuit
DC voltage
=
√2 x mains voltage [V].
4
. Intermediate circuit coils
Evens out the intermediate circuit current and limits
the load on mains and components (mains trans-
former, cables, fuses and contactors).
5
. Intermediate circuit capacitor
Evens out the intermediate circuit voltage.
6
. Inverter
Converts DC voltage into a variable AC voltage with
a variable frequency.
7
. Motor voltage
Variable AC voltage depending on supply voltage.
Variable frequency: 0.2 - 132 / 1 - 1000 Hz.
8
. Control card
Here is the computer that controls the inverter which
generates the pulse pattern by which the DC voltage
is converted into variable AC voltage with a variable
frequency.
■ The decentral concept
The FCD 300 Adjustable speed drive is designed for
decentral mounting, e.g. in the food and beverage
industry, in the automotive industry, or for other ma-
terial handling applications.
With the FCD 300 it is possible to utilize the cost
saving potential by placing the power electronics de-
centrally, and thus make the central panels obsolete
saving cost, space and effort for installation and
wiring.
The unit is flexible in its mounting options for as well
stand alone mounting and motor mounting. It is also
possible to have the unit pre-mounted on a Danfoss
Bauer geared motor (3 in one solution). The basic
design with a plugable electronic part and a flexible
and “spacious” wiring box is extremely service-
friendly and easy to change electronics without the
need for unwiring.
The FCD 300 is a part of the VLT frequency con-
verter family, which means similar funcionality ,
programming, and operating as the other family
members.
■ Cleaning
The enclosure (IP66/NEMA type 4x indoor) will offer
protection against dirt and water ingress, and is de-
signed suitable for cleaning as performed in food and
beverage plants with the concentrations of cleaning
solvent as recommended by the manufacturer. High
pressure cleaning in very short distance or long time
with hot water may damage gaskets and lables.
■ FCD 300 control principle
A frequency converter is an electronic unit which is
able to infinitely variably control the rpm of an AC
motor. The frequency converter governs the motor
speed by converting the regular voltage and fre-
quency from mains, e.g. 400 V / 50 Hz, into variable
magnitudes. Today the frequency converter con-
trolled AC motor is a natural part of all types of
automated plants.
The FCD 300 Series has an inverter control system
called VVC (Voltage Vector Control). VVC controls
an induction motor by energizing with a variable fre-
quency and a voltage suitable for it. If the motor load
changes, so does its energizing and speed. That is
why the motor current is measured on an ongoing
MG.04.A1.02 - VLT is a registered Danfoss trade mark
5
Introduction to FCD 300
To Next Page
Loading...
Need help?
General