Sine Wave 2-8 kHz Series A Filter
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Part No. INSTR-020 REL. 080310
8. FILTER DESCRIPTION
The MTE Series A Sine Wave Filter is a
low pass filter containing proprietary
technology, which makes it particularly
useful for filtering the output of PWM
inverters. The filter consists of a reactor
and a resistor capacitor network.
shows a block diagram of the filter. The
PWM output from the inverter is connected
to the input terminals of the reactor. The
load, which can be either a motor or a
transformer, is connected to the output
terminals of the reactor.
MTE Series A sine-wave filters are
designed to provide a sine wave output
voltage when driven from PWM inverters
with switching frequencies from 2 kHz to 8
kHz. For drive applications, these filters
eliminate the problem of motor insulation
failures and they also reduce
electromagnetic interference by
eliminating the high dv/dt associated with
inverter output wave forms. For alternate
energy applications where an inverter is
used to return power to the utility
distribution system through a step up
transformer these filters meet the
requirements of IEEE 519.
Sine wave filters are available in open
panel, NEMA 1, 2, and 3R mechanical
configurations. For both variable torque
and constant torque applications, select
filters based on the horsepower rating of
the motor. Filter current ratings have been
designed to meet the requirements of NEC
motor current ratings. For applications that
use motors with current ratings that
exceed NEC values selected a filter with a
current rating equal to or greater than that
of the load.
For inverters feeding isolation
transformers select a filter with a current
rating equal to or greater than that of the
transformer primary current.
Typical applications for Series A sine-
wave filters are submersible pumps, low
voltage drives feeding medium voltage
motors, HVAC equipment, wind turbines
and applications where the distance
between the motor and inverter is up to
15,000 feet.
Note: Series A sine-wave filters can only
be used with PWM inverters with switching
frequencies set between 2 and 8 kHz.
For voltages other than 440-480, 550-600
VAC, contact the factory.
Filters for motors that will be operated
above 60 Hz should be selected based on
the frequency de-rating curve
(
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Summary of Contents for Sine Wave Filter
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