Artesis AMT Toolkit, Руководство пользователя

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Equipment Faults, Diagnosis and Reporting
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Power factor is below 0.7. This indicates that the motor is running at less than 50%
of its full load. Hence, its operation is less efficient (1% - 5%) compared to its full
load operation. It is advised to continue using this motor until a developing fault
exists. At that time, consider replacing it with its low power counterpart if return
on investment (ROI) is acceptable.
Current and Voltage
The average RMS value of the phase currents exceeds 10% of the nominal current
values. Monitor for increased hot spot temperature.
Voltage variation is beyond (+/-10%) normal limits. Its source should be
determined and corrected.
Harmonic Distortion
There is high harmonic distortion. If Total Harmonic Distortion (THD) is more than
5%, this causes heating, and vibration. A high third harmonic can cause heating in
the stator windings. A high fifth harmonic can cause vibration. Use harmonic filter
if feasible.
EEE: Harmonic distortion cause loss in energy efficiency up to 1%
Current and Voltage Unbalance
Current unbalance exceeds 5%. Check for stator problems, short circuits, isolation
problems, partial discharge, etc.
Voltage unbalance exceeds 2%. Voltage unbalance will cause heating and will result
in current unbalance.
EEE: Voltage and current unbalance cause heat and up to 3% energy efficiency
problems.
The electrical parameters, their definitions and their expected values are given below:
Power Factor: The power factor of an electric motor system is defined as the ratio of the
active power (flowing to the load) to the apparent power, and is a number between 0 and
1. Active power is the capacity of the motor for performing work in a particular time.
Apparent power is the product of the current and voltage of the motor. A load with low
power factor draws more current than a load with a high power factor for the same amount
of useful power transferred. Because of the cost of wasted energy, electrical utilities will
usually charge a higher cost to industrial or commercial customers where there is a low
power factor. Software alerts the user when the power factor goes below a value of 0.7.
Active Power: The actual amount of power being used, or dissipated, by the motor is called
actual power (also called real power or true power), and it is measured in Watts. Active
power of the electrical motor could be obtained by summing output power and losses.
Reactive Power: Reactive loads such as inductors and capacitors dissipate zero power, yet
the fact that they drop voltage and draw current gives the deceptive impression that they
actually do dissipate power. This “phantom power” is called reactive power, and it is