Amtech Axpert-Eazy Series Instruction Manual page 185

CHAPTER-9: OPTIONS
Besides the standard features available in the Axpert-Eazy series AC DRIVE, which satisfies most of
the industrial applications, AMTECH offers its users a spectrum of optional products designed to
match their requirement.
The list of optional products offered by AMTECH herewith is all developed, field tested and
commissioned at various locations in India. A brief description of the option is given. Contact
AMTECH with relevant data to design one for you.
9-1 Green Power Technology
Non-linear loads like AC DRIVE, UPS, Converters etc. draw power from mains in a way, which
introduce harmonic currents into the mains. They behave like harmonic source, which feeds harmonic
to all the equipments, connected with the power source. IEEE STD 519: 1992; IEEE Recommended
Practices and Requirements for Harmonic Control in Electric Power System states that it is the
responsibility of the consumer to curb this mains 'Pollution' at the source point itself within acceptable
limits.
AMTECH offers Input Harmonic Converter as a solution for this problem. As per the requirement and
acceptable limits of induced harmonics such converters can be tailor made for you. Contact AMTECH
for details on Input Harmonic Converter.
9-2 Output Sinus Filter
Output of any AC DRIVE is Sine PWM (Pulse Width Modulation) modulated at high frequency carrier
wave. When this kind of waveform encounters motor load, it tends to create very high dV/dt stress for
the stator winding. After a long time the stator insulation gets weakened up and ultimately the stator
flashover takes place. The problem is particularly severe in places where the location of motor and AC
DRIVE is at large distance. This happens because of the impedance mismatch between cable and
the motor surge impedance. This can reach as high as 1.9 times the DC bus voltage.
Output Sinus Filter helps to outcome this problem. The output after sinus filter becomes sinusoidal
and the Motor gets relieved from excessive dV/dt stress. Motor can be placed far away from AC
DRIVE. The motor loss due to harmonic heating also reduces considerably.
Output Sinus Filter also helps in controlling the EMI and RFI generated by the power cable and motor.
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That means an added advantage for equipments operating with small voltages and high frequencies.
Contact AMTECH for details on Output Sinus Filter.
9-3 Input/ Output Filter
Input filter is installed before the converter stage of the any AC DRIVE to smoothen the current drawn
from mains power supply. This also improves the wave shape at the input, as the peak value of drawn
current is restricted and the mains transformer do not goes towards saturation.
Output filter with around 3% impedance helps in changing the characteristic impedance of the motor.
Now the AC DRIVE sees the output filter as the reflecting impedance and the filtering choke bears the
dV/dt spikes. Thus the dV/dt transient do not hampers the motor thereby increasing its insulation life
and reduced heating. Alternatively RC Filters and LC Filters and other passive component
combinations are also designed to suit a particular requirement. For sizing and best filter selection for
your system, contact AMTECH.
9-4 Metering
At times there may be need of monitoring the internal AC DRIVE data. Optional analog or digital
metering of AC DRIVE operating data like various voltages, currents, rpm etc can be provided in the
panel. For the AC DRIVE data, which can be monitored, and the extra hardware, contact AMTECH for
details.
Axpert-Eazy AC Variable Frequency Drive
9.1