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Motor Current Signature Analysis

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Motor Current Signature Analysis is the online analysis of current to detect faults in a single/three phase induction motor drive while it is still operational and in service. The possible defects caused in motor current signature is Broken Rotor Bar, Numerous Broken Bar, Stator Core and Winding Damage, Broken and Damaged Bars and Core Damage due to excessive heating, Abnormal Airgap Eccentricity and certain mechanical problems train characteristics.

Electrical Signature Analysis

Electrical Signature Analysis (ESA) consists of the frequency-domain representation, processing, and analysis of electrical signals and has been usually applied in electric machinery condition monitoring. In general, ESA comprises of an FFT (Fast Fourier Transform) algorithm to represent the time-domain signals in the shape of spectra, which are referred in this work as electrical signatures. ESA is based on the assumption that a significant change in a machine condition results in the change of its electrical signature. Moreover, there are specific frequency components whose magnitudes change in the presence of faults. These frequency components are related to the type and location of fault, being dependent on the power line frequency and structural characteristics of the motor or generator. Thus, it is possible to obtain a set of ESA fault patterns for fault detection and identification in electrical machines.

Electrical Signature Analysis

The major faults of electrical machines that can be identified by MCSA include

Electrical Signature Analysis

Bearing damage


Shorted turns in stator windings

Air-gap eccentricity: a non-uniform air gap between the rotor and the stator

Load effects

Equipment wear effects

Broken rotor bars that can cause sparking and overheating

The data obtaining during ESA testing includes

Crest Factor

Current Spectral Analysis


Phase-to-phase Voltage RMS

Total Harmonic Distortion (THD)

% Full Load Amps

High Frequency Eccentricity Analysis


Phase Current RMS

Phase Impedance

Power Factor


Output Power

Average Current RMS

Line-to-Neutral Voltage RMS

Voltage Imbalance

Impedance Imbalance

Power (KW, KVA, KVAR)

Successful Applications using MCSA

AC/DC Motors


Machine Tool Motors

Transmission & Distribution Transformers

Servo Motors

AC/DC Traction Motors

Control Transformers

(Virtually Any Size)

For Commissioning Testing

For Troubleshooting

For Reliability Testing