1563   About scl:count (array manipulation)

Created: 09 Dec 2016

Status: In Force (green)

Part: Part 6 (2009-12; Edition 2)


Page: 103,and other pages



Category: No impact on this part


As stated by the standard, scl:count can reference an attribute which shall exists in the same type definition. This leaves a lot of room for very complex implementation. If the referenced attribute is instantiated in LN, it is configurable, and array attribute should be instantiated according to the instance of referenced attribute. This will make the array size of the attribute instances within LNs with the same LNodeType id varied, which make it very hard for stack to implement, and also in engineering process, the array signal is unable to handle unless to handle it as a whole data. Because its size may be changed when the server is running by a client. The engineering tool may reference a dangle signal like stVal[10] which is not exist when the array size is changed to 5;


The referenced attribute (namly scl:DA, scl:BDA) should have a child element scl:Val to indicate the array size (defaul is 0).

Discussion Created Status
Not accepted 22 Mar 17 In Force (green)
Not accepted. Adding a value to the count attribute (as was allowed in Ed1) makes things even more complicated, as then there exist two sources for the size. It is up to the IED (and stack) implementation to decide which 8value override9 functions for the value of the count attribute are supported and which not. 14 Dec 16 Discussion (red)
Type definition as followed:
<LNodeType id="MMXU_TYPE" lnClass="MMXU">
<DO name="Har" type="HWYE"/>
<DOType cdc="HWYE" id="HWYE">
<DA bType="Struct" count="numOfHar" dchg="true" dupd="true" fc="MX" name="phsAHar" type="Vector"/>
<DA bType="INT32" fc="CF" name="numOfHar">

Instantiated LNs as followed:
<LN inst="1" lnClass="MMXU" lnType="MMXU_TYPE">
<DOI name="Har">
<SDI name="phsAHar"/>
<DAI name="numOfHar">

<LN inst="2" lnClass="MMXU" lnType="MMXU_TYPE">
<DOI name="Har">
<SDI name="phsAHar"/>
<DAI name="numOfHar">

The first LN is instantiated with default value 7, and the phsAHar should be an array with size of 7. For the second LN, the phsAHar is 10. the numOfHar can not be changed by any client. The question is that phsAHar should be engineering as one signal or it is also allowed to handle as "partial signal" like phasAHar[5], this could complex the engineering process.
13 Dec 16 Triage


Privacy | Contact | Disclaimer

Tissue DB v.