I am on a site where all MkV SDCC JP23 jumpers are set to 1/2. The MkV manual advises that these jumpers should be set to 2/3. The panel appears to behave correctly. Should these all be changed to 1/2 and if so what difference should I expect? On checking the spare cards in storage I fnd that the jumper on them is set to 2/3. Thanks in advance.

 

Er, .., Um, ..., Which MkV manual would that be (including revision designation (a single alpha character after the GE publication number)--and what section (not page number, but section and subsection, if appropriate)?

I, for one, am LOATHE to put any jumper on a card in any position other than the one it was found in based on some piece of paper--especially on the Mark* V (or the Mark* IV, for that matter). If the unit is running well and behaving correctly with no Diagnasty Alarms, then it's probably in the correct position for that version of Mark*. (Do you know what version of Mark* panel the site has? A, B, Hybrid A or Hybrid B? Sometimes when you run CARD_ID.EXE it says, but usually only on newer versions of the Mark* V panel and PROMsets, and usually only with newer versions of IDOS or TCI.)

Unfortunately, lots of variables. Remember: The DCC/SDCC cards were also used in variable speed drives produced in GE Salem, and sometimes, the jumper functions were unused in the turbine control application. Not always, but sometimes. (Keeps life interesting, doesn't it?)

 

I am on a site where all MkV SDCC JP23 jumpers are set to 1/2. The MkV manual advises that these jumpers should be set to 2/3. The panel appears to behave correctly. Should these all be changed to 1/2 and if so what difference should I expect? On checking the spare cards in storage I fnd that the jumper on them is set to 2/3. Thanks in advance.

These Jumpers position is set to 2/3 for "Direct Memory Access" must be in 2-3 for Mark V applications as per OEM manual

 

These Jumpers position is set to 2/3 for "Direct Memory Access" must be in 2-3 for Mark V applications as per OEM manual

Thanks ControlsGuy25, I also have asked around colleagues on other sites where same generation of MkV is. True B panels and all JP23 to 2/3. I’ve changed and all seems well so far after reboot.

 

Thanks @TheGingerbeer for the update/feedback

Stay safe & blessed !

 

Adding to the thread for posterity and responding to unanswered questions and providing a conclusion. The panel is a true B panel. The MKV manual to which I made reference is GEH-6195H, Appendix A, Page A-4. JP23 on SDCC been in 2-3 now for 3 weeks without any noticeable performance change or generation of diagnostics or other errors. Either its a "don't care" for MkV or incremental improvement is not dissernible. I been messing with MKV since before they were in the marketplace and this jumper I have not experienced issues with before. Am concluding that it is now in the correct position and was incorrectly positioned before. Customer has said that in the long term (2-3 months of operation) some errors would appear on the green screen on <C> - does not recollect what they were. Fingers crossed these will not now occur. Again thanks to all respondents for your advice and time.

 

Thank you for the updating !

 

We recently replaced a SDCCG5A card and noticed this jumper JP23 was also set at 1/2. It was set at that on the old card that had been operating for years and we left it like that on the new card. The other two control processors were set at 2/3.

As a side note when we changed the SDDC card and downloaded all we still had a couple of alarms in that were coming from P core so we had to reboot Y core and then all the alarms cleared. I never saw that step in any of the documentation I read on this forum or in the manuals.