TCI KMG - Manual (Page 9)

9
Product Description
MotorGuard Sine Wave Filter
The MotorGuard is a low-pass sine wave filter designed and developed by TCI to deliver conditioned
power to motor loads driven by PWM drives at a variety of lead lengths. The MotorGuard is available
for 460/480 volt and 575/600 volt systems.
The MotorGuard is a passive filter connected in series with the output terminals of the variable
frequency drive. It is designed to remove the carrier frequency distortion from the output voltage
waveform. The use of this low-pass, L-R-C device will result in a nearly pure sine wave voltage
profile. This design will reduce the effects of the reflected wave phenomenon, (dv/dt), such as
insulation damage or premature failure in motors, transformers and VFD output cables. The
MotorGuard will also reduce the effects of stray high frequency harmonic currents, thereby reducing
VFD ground fault problems and noise interference in transducer signals.
The MotorGuard is available in two package configurations: Industrial and GP. The Industrial filter is
a stand-alone device that can be furnished in its own enclosure and mounted adjacent to the VFD, and
is also available on an open panel for mounting within an enclosure provided with the VFD or other
equipment. The GP filter is furnished in its own enclosure and mounted adjacent to the VFD.
The MotorGuard is suitable for all lead lengths extending as far as 15,000 feet.
The MotorGuard consists of the following standard features and components:
♦ An R-L-C power filter circuit with:
A TCI 3-phase reactor specifically designed for the MotorGuard
Power resistors
High-endurance, harmonic-rated capacitors
♦ Bleeder resistors to ensure safe capacitor discharge upon filter shutdown.
♦ Compression terminals for ease and integrity of all power wiring.
♦ Cooling fans to ensure adequate cooling and safe operating temperatures.
Optional Monitor Board is available:
♦ A filter performance monitor and alarm circuit with:
Monitor board with relay and status indicating lights
Control transformer for control voltage power
Compression terminal blocks for all control wiring