Mark V card revision


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I was wondering if I could replace an existing Mark V module with a newer revision module. For example let say for the TCDA module, my current revision is TCDAG1ABA and the new revision is TCDAH1B. I believe that the H is a major revision and would not work as the replacement. Is it correct? If yes is there any way to make it work?
It's been a long time, but I believe GE are no longer manufacturing TCDAGnx cards, and some new process or components are being used for the same functionality on TCDAHnx cards.

I believe this topic has been covered before on; use the 'Search' function for possible related threads.

You could also ask GE or one of their packagers this question to be absolutely certain.
This might be a little longer but now the time has come for me to replace a faulty TCDAG1A.

I did contact GE on the matter and I was informed that the TCDAH1B is the direct replacement for the TCDAG1A but it has an additional berg jumper JP9 which need to be set according to the EEPROM revision.

The TCDA on <R> gave up last week and I tried to replace it with the new TCDAH1B and set my JP9 to B position as the EEPROM is DS200F1ACM revision. The <R> core managed to boot to A7 but the LED indication on the TCDA seem to be momentarily "out of sync" with the other TCDA. After some time LED #2 to #10 stays light and voter mismatch alarms on <R> is announciated on HMI.

Anyone has experienced similar problem before?
The remaining TCDAs on <S, T, and CD> are still TCDAG1A.
Good news.
It happens to be that the new card that was replaced was not in good condition (possibly faulty).

The problem was solved after the TCDAH1B was replaced with another new spare :)
Yes; "spares" have been known to be bad "out of the box" also (unfortunately).

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