WEG CFW11W G2 Series User Manual page 9

General Information
Pre-Charge Circuit: it loads the capacitors of the DC link with limited current, avoiding high current peaks at the
inverter energization.
DC Link: intermediate circuit of the inverters; voltage in direct current obtained by rectifying the alternate supply
voltage or through an external power supply; it supplies the output inverter bridge of the inverters composed of
IGBTs.
DC+: positive terminal of the DC Link.
2
DC-: negative terminal of the DC Link.
Arm U, V and W: 2-IGBT set of the inverter output phases U, V and W.
IGBT: insulated Gate Bipolar Transistor, basic component of the output inverters. They work as an electronic
switch in the saturated (closed switch) and cut-off (open switch) modes.
Braking IGBT: it works as a switch to turn on the braking resistors. It is controlled by the DC link level.
PTC: resistor whose resistance value in ohms increases proportionally to the temperature; used as temperature
sensor on motors.
NTC: resistor whose resistance value in ohms decreases proportionally to the temperature increase; used as
temperature sensor on power packs.
HMI: Human-Machine Interface; device which allows controlling the motor, viewing and changing the inverter
parameters. The HMI of the CFW11W G2 has keys to control the motor, navigation keys and a graphic LCD display.
FLASH Memory: nonvolatile memory that can be electrically written and erased.
RAM memory: random access memory.
USB: Universal Serial Bus; serial communication protocol conceived to work according to the plug-and-play
concept.
PE: protective earth.
RFI Filter: radio Frequency Interference Filter; filter to reduce interference in the radio frequency band.
PWM: pulse Width Modulation; pulsed voltage generated by the output inverter which feeds the motor.
Switching Frequency: switching frequency of the IGBTs of the inverter bridge, normally expressed in kHz.
General Enable: function of the inverter that, when enabled, accelerates the motor by acceleration ramp. When
disabled, the PWM pulses will be immediately blocked. It may be controlled by a digital input programmed for
this function or via serial.
Run/Stop: function of the inverter that, when enabled (run), accelerates the motor by acceleration ramp up to the
reference speed, and, when disabled (stop), decelerates the motor by deceleration ramp until full stop, when the
PWM pulses are then blocked. It may be controlled by a digital input programmed for this function or via serial.
The HMI (Run) and (Stop) keys operate in a similar way.
Heatsink: piece of metal designed to dissipate the heat generated by power semiconductors.
UP11W G2: power Unit of the CFW11W G2.
UC11 G2: control Unit of the CFW11W G2.
PLC: programmable logic controller.
Amp, A: ampere.
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