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CA08103002Z-EN
www.eaton.comFrequency inverters
General information about engineering information
10/23
General informationaboutengineering information
Engineering
Item designations
F = fuses and circuit-breakers
Q = controlled switching within energy flow (contactors, circuit-breakers)
R = limitation (reactors, chokes, resistors)
K = radio interference suppression filters
T = frequency inverters
M = motors
M
3
~
3
~
F
Q
R
R
K
T
M
3
I
OK
BACK
RESET
LOC
REM
R
3
Frequency inverters
can be connected without limitation to AC supply systems
with a grounded star point (TN and TT networks).
Fuses (circuit-breakers)
allow the protection of lines and electrical
apparatus.
For personnel protection AC/DC-sensitive residual current devices
(
RCD Type B) are required in addition.
Contactors
are used to switch mains voltage on and off.
Mains chokes
attenuate any current harmonics and peaks and limit the inrush
current (internal DC link capacitors).
Radio interference suppression filters
attenuate high-frequency electro-
magnetic emissions from devices. They ensure that the EMC limit values for
conducted interference specified in the applicable product standards are
maintained
(
frequency inverters).
Frequency inverters
allow a continuously variable speed control of three-phase
motors.
A braking resistor
convert the frequency inverter’s regenerative braking
energy into heat.
The frequency inverter must be equipped with a brake chopper, which connects
the braking resistor parallel to the internal DC link.
Motor chokes
•
Compensate the capacitive reactive currents,
•
Reduce current ripple and the motor’s current change noise,
•
Attenuate the retroaction on parallel connection of several motors.
Sine-wave filters
•
Smoothen the output voltage sinusoidally,
•
Reduce motor noise through du/dt reduction, and thereby increase the
motor insulation’s lifespan,
•
Reduce the leakage currents to allow better motor performance at
improved EMC values.
Shielded motor cables
attenuate emitted and conducted high-frequency
emissions within the limit values specified in the applicable product standard
(
EMC).
Three-phase asynchronous motor (standard motor)
Components of a Power Drives System (PDS)