Product Overview
MTE Motor Protection Filters are designed to protect AC motors from the destructive affects of long cable runs between an inverter and motor.
Three type
- dv/dt Series A Filter
- 2-8Khz Series A Sine Wave Filter
- Motor Protection (LC) 5KHz Sine Wave Filter
dv/dt Series A Filter
The dV/dt filters are designed to protect AC motors from the destructive effects of peak voltages facilitated by long cable runs between the inverter and motor. Depending on the switching time of the power semiconductor used in the inverter and the size of the motor, cable lengths as short as eight feet can result in motor peak voltages that exceed the rating of the motor’s insulation system. However, the longer the cable the greater the problem.
The dV/dt filter help meet its maximum peak motor voltage specification (150% of bus voltage) with up to 1,000 feet of cable between the filter and the motor. It is also rated for a maximum dV/dT of 200 volts per microsecond. However, in specific applications, the filter has provided excellent performance with cable runs up to 3,000 feet.
The dV/dt filter has a “3% insertion impedance” which ensures motor torque is not affected by added voltage drops from the filter.
The dV/dt filter is a passive fourth order device that reduces transmission line effects of motor cables by dampening the rate of voltage increase and minimizes the peak voltage that occurs at the motor terminals.
The dV/dt filters are designed for use with inverters operated at switching frequencies between 900 Hz and 8 kHz.
The dV/dt filter has a continuous current rating of 100% RMS and intermittent current of 150% for 1 minute and 200% for 10 seconds. Available as panel-mount or in NEMA 1, 2 and 3R enclosures the new dV/dt filter is rated for use in temperatures up to 50° C as panel mount or 40° C with enclosed cabinets.
Typical applications include submersible pumps, HVAC equipment and process automation lines. Motors rated 100 hp and below and standard NEMA B motors, MG1 Part 30, are prone to failure as a result of high voltage spikes and will benefit from dV/dt filtering.
Series A Sine Wave Filter
New MTE Series A sine-wave filters 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 reduce electromagnetic interference by eliminating the high dV/dT associated with inverter output waveforms.
For alternative energy applications, such as wind driven generators, 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 and permit the use of standard transformers. Harmonic voltage distortion feeding a transformer at full load and at 50 Hz is 5% maximum. Harmonic voltage distortion feeding a motor at full load and at 50 Hz is 5% typical.
Sine Wave Filters help eliminate the high dV/dT associated with inverter output waveforms in applications where the distance between the motor and the inverter is up to 15,000 feet.
The Sine wave filter is available in 440 – 480 VAC and 550 – 600 VAC for motors from 1.5 to 700 hp. Panel-mount or NEMA 1, 2 and 3R enclosures are available. Typical applications include submersible pumps, low voltage drives feeding medium voltage motors, HVAC equipment, wind turbines and applications where the distance between the motor and the inverter is up to 15,000 feet. The Sine Wave filter has a continuous current rating of 100% RMS and intermittent current of 150% for 1 minute.
Related Information :
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