This tissue has following status: blue
Created: 15 Mar 2005
Clause: Several issues
Category: No impact on this part
Issue: contribution to comments 9, 10, 11 ,12 (old numbering!!)
1. why do you need the Sel attribute for the AMV? If you have just the others (saying by name what they mean) you can select one or all of them. By the way, what should be the meaning of the mag itself in the AMV?
General question: which approach shall be taken: Putting this differences into CDCs like you suggest, or into DATA as done in 7-4? Doing both is at the end confusing - at least there should be strong guideline when to use what. It seems that if you need some additional CF attributes, then up to now we used CDC - especially if this were the same attributes for several values (e.g of all three phases). However, there could also be the strategy to have some attributes (like rmsTmms) common for all rms data within one LD. In this case the difference should be in the DATA (not in the CDC), and at LLN0 we add a separate RmsTmms ING DATA, then valid for ALL rms values of the LD.
3. as all values may be polled as well as reported, the dead banded value calculation must be independent from reporting. Therefore it starts when the appropriate LNs Mod is set to ON, i.e. normally when the IED starts up.
4. I hinted already earlier to the need for two deadband values. The response there was, that db is a percent value and can therefore be used for all quantities (mag and ang).
New suggestion of CDC: Why did we not introduce a Vector based CDC for Power? It contains then W (mag * sin(ang)), VAr (mag* cos(ang)), VA (mag) and PwrFact (ang) with only two values!
Proposal: Take into account.