Easergy P3 [P3T32] FW V30.204-1 2nd & 5th Harmonic Block Enable

[PaterninaEnriqu]

Hello.

I am writing to find out if anyone knows what happened with the 2nd and 5th harmonic blocking function in version FW30-204-1 and how it should be implemented in this firmware version.

Below, I attach the print-screen comparing the two firmware versions.

Fig. 1 Comparison in archive FW30.204-1 and FW30.109.

 I tried using functions 68F2 and 68H5 (available in both firmware versions) to block the 87T from working, but it didn't work.

Fig. 2. 68F2 and 68H5 available in firmware V30.204-1 and V30.109.

Fig. 3 Blocking matrix for function 87-1 and 87-2.

In previous firmwares this feature was embedded in the 87-1 function and it worked fine.

I remain attentive to any comments or suggestions.

[Juha · Accepted solution]

Hi @PaterninaEnriqu and thanks for your question.

Yes, indeed Easergy P3 differentials stage dI> has changed. Removal of 5th harmonic blocking is not the only changes other are invisible.

The differential stage dI> has been improved for better handing of the primary CT saturation. This allows to re-write the CT selection guidance and allow to use smaller primary CT's. That is clear benefit.

While this was done, the 2nd harmonic restrain was improved too (available from version 30.204). The inrush blocking (2nd harmonic) is improved such that it has an addition criteria for the 2nd harmonic blocking. This additional criteria requires the power transformer to change from non-energized condition to energized condition. This is made in order to improve the inrush detection security.

When all these changes were made, the 5th harmonic blocking was removed from the dI> stage. We removed the 5th harmonic blocking as we wanted to improved it also but we faced some time constraints. The 5th harmonic blocking is still available as separate function. The separate 5th harmonic blocking can be used to block the dI> stage via the blocking matrix.

For more information, please do not hesitate to contact me directly by an email or teams.

BR

-juha-