Line Reactor/Dc Bus Choke - WEG CFW-09 User Manual

8.7 LINE REACTOR /
DC BUS CHOKE
CHAPTER 8 - CFW-09 OPTIONS AND ACCESSORIES
Figure 8.18 - RS-232 module
The RS-232 PC Communication Kit which allows the connection of the CFW-09
to a PC via the RS-232 interface is composed of:
RS-232 Serial Interface Module;
3 m (10 ft) Cable for RJ-11 to DB9 connection;
SuperDrive Software for Windows for CFW-09 programming, operation and
monitoring. Refer to hardware and system needs for SuperDrive.
To install the RS-232 PC communication kit, proceed as follows:
Remove the keypad (HMI) from the inverter;
Install RS-232 Serial Interface Module in place of the keypad;
Install the SuperDrive software in the PC. Consult the on-line help or
installation guide;
Use the cable to connect the inverter to the PC;
Follow the SuperDrive software instructions. Consult the on-line help or
installation guide.
Due to the input circuit characteristic, common to all passive front end inverters
available in the market, which consists of a six diode rectifier and capacitor
bank, the input current (drained from the power supply line) of inverters is non
sinusoidal and contains harmonics of the fundamental frequency.
These harmonic currents circulate through the power supply line, causing
harmonic voltage drops which distort the power supply voltage of the inverter
and other loads connected to this line. These harmonic current and voltage
distortions may increase the electrical losses in the installation, overheating
components (cables, transformers, capacitor banks, motors, etc.), as well as
a lowering power factor.
The harmonic input currents depend on the impedance values that are present
in the rectifier input/output circuit. The addition of a line reactor and/or DC bus
choke reduces the current harmonic content, providing the following advantages:
Increased input power factor;
Reduced RMS input current;
Reduced power supply voltage distortion;
Increased life of the DC Link capacitors.
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