SFRA45 – Sweep Frequency Response Analyzer

Demystifying SFRA

The Sweep Frequency Response Analyzer simply injects a range of frequencies into a winding of a power transformer, when the power transformer is built correctly with no imperfections and faults the frequency response (of Gain Vs Frequency) plot of that particular type of transformer and winding on that particular transformer should exhibit a particular shape, this “shape” then becomes the transformers “fingerprint”.

Over the course of the transformers lifetime this “fingerprint” can be used in order to detect degradation of the transformer.

Proven technology

Utilising the latest DSP and FPGA technology to optimise the use of innovative analogue hardware, many measurements functions can be derived with great precision from the basic elements of true rms voltage on two measurement channels plus the phase angle between them. It is from this fundamental relationship between independent voltages and their relative phase angle that the phrase 'Phase Sensitive Multimeter' was derived and this is also the key to the unique combination of performance, versatility and value provided by the PSM range.

Whether you will make use of just one or all six of the primary measurement modes included in the PSM1700 and PSM1735, you can be sure of exceptional accuracy, speed and ease of use that only the latest design technology can provide.

When is SFRA performed?

There are three main occasions when SFRA is performed

1. Upon factory quality checking
2. Before a short circuit test
3. Before and After transportation