Category: Issue may impact interoperability of implementations of Edition 2
Issue
(identified and submitted by J-L. Sanson & A. Maizener as UML issue)
In 7-4, we have Tm = Time, that could be expressed as h, min, s and ms. This is done through naming convention for DO that imposes the unit and potentially a multiplier:
- Tmh = Time in h
- Tmm = Time in min
- Tms = Time in s
- Tmms = Time in ms
We should be able to reflect unit and multiplier in the corresponding DO (i.e. CDC) DataAttributes "units" with an SIUnit and multiplier.
Example : KFAN.MinOpTmm whose type is ING.
We could do that with 's' and 'ms' (because defined in Unit and Multiplier enums), but 'h' and 'min' are not defined and thus cannot be used for instance as units for curves...
'h' and 'min' are "units that are not part of the SI but are essential and used so widely that they are accepted by the CIPM, and thus accepted to be used with the SI".
Proposal
Add literals 'h' and 'min' to UnitKind (and assign order/integer value different from any existing one, to preserve backwards compatibility).
Discussion
Created
Status
UML Editor meeting:
The enum numbers shall be: h=84, min=85
21 Sep 12
In Force (green)
13 Nov 11
In Force (green)
Proposed solution:
- Add 'h' and 'min' to the unit enumeration in 7-3
- For DOs, where the unit is defined in the name, the data attribute "units" (if present) shall be read only. This shall be added as explanation in part 7-4 where the naming convention is defined.
18 Jul 11
Ballot Period
We should not change DO names which exist. The problem arises because in Ed.2 INS, INC, ING have gotten a 'unit' attribute, whose value can not be set according to the unit indicated in the name. Either we forbid the unit attribute at 7-4 level if the unit is in the DO name, or we add the appropriate units to allow a consistent definition.
09 Jun 11
Discussion (red)
If - from a interoperability viewpoint, we want to restrict the selection of the units for the time (e.g. in the above example, we require that the granularity of the operation time is minutes), we provide the required unit in the name. In that case, the units attribute should not be present or should be fixed to the value that corresponds to what we have in the name. Otherwise, we may produce incosistent configurations.
For the cases, we do not want to restrict it, it may be aceptable to support as well units h and min. Under this perspective, we should review the DO names.