559 LN KVLV

Created
15 Oct 2007
Status
Discussion (red)Open for discussion while the solution is worked out. Any signed-in reader may comment. Show the workflow
Part
Part 7-410 (2007; Hydro Power)
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None
Page
Clause
7.5.6
Paragraph
Category
Issue for edition 2 of this part

Issue

PosSpt uses CDC APC but “control” operations are not needed

Proposal

Change to CDC ASG

DiscussionCreated
Discussion (red) If in principle remote control by an operator or some automatics with varying positions during the operation is needed, then APC should be used - or, if its always full percentage, INC. As Thierry indicated, for pure position indications then ctlModel=status-only can be used. ASG is used for function parameter settings changed very seldom by (protection) engineers, not an operational value adapted by an operator. 22 Oct 07
Discussion (red) I'm not sure that using a setting is a correct modeling. If the devices are positioned manually, then using a APC with the control model set to "status only" does it very well.
I'm not aware of ASG whose chages are reported to reflect external influences.
22 Oct 07
Triage This leads to a question about the modelling of KFAN, KPMP as well. In all three cases we have devices that could be continuously controlled 0 - 100%. Either this can be modelled as ASG under controls, with the return value reported as MV under measured value or as just a APC under controls.

Compare with YEFN in part 7-4 (this is actually the only LN that makes use of APC). In YEFN it is the position of the core in a plunge core neutral reactor that is controlled.

The problem is that KFAN, KPMP and KVLV might represent devices that are positioned manually, only the actual position being reported. Since all controls are optional, it might be better to do as proposed and change to ASG.
22 Oct 07