How many instances of each LN?
As per 7-4 Ed2 cl 5.11.1
· If there are several stages to one function (i.e. for multi-zone relay), each stage shall be a separate instance of the LN. Examples are PDIS (n zones) or PTOV (2 stages).
· Multiple instances shall be used if LNs of the same LN class are operating with different settings in parallel.
So you definitely need 3 PDIS for a 3 zone relay
What is perhaps arguable is whether you would prefer to have the following (noting there is no generic .StrVal for PDIS)
Z1P-PDIS.PhStr = something
Z1P-PDIS.GndStr = n/a
Z1G-PDIS.PhStr = n/a
Z1G-PDIS.GndStr = something
With corresponding
Z1P-PDIS.Op and Z1G-PDIS.Op
– this would imply 6 PDIS for a 3 zone relay (Z1P-, Z1G-, Z2P-, Z2G-, Z3P-, Z3G-)
But equally crystal clear is just
Z1-PDIS.PhStr
Z1-PDIS.Gnd.Str
Similarly Z1-PDIS.Op.phsA vs Z1-PDIS.Op.neut is also crystal clear
In which case you use the power of the defined semantic to only need 3 PDIS for a 3 zone relay (Z1-, Z2-, Z3-)
Same goes for PTOC for a 3 stage OC and 3 stage EF relay
I talk about this in my Modelling slides as per attached (let me know if you want to register for the next course …. J )
As you can see if I use individual instances Z1P-PDIS and Z1G-PDIS, then Aph-G Z1 fault
Z1P-PDIS.Op.phsA = 1
Z1P-PDIS.Op.phsB = 0
Z1P-PDIS.Op.phsC = 0
Z1P-PDIS.Op.neut = n/a
Z1P-PDIS.Op.general = 1
Z1G-PDIS.Op.phsA = n/a
Z1G-PDIS.Op.phsB = n/a
Z1G-PDIS.Op.phsC = n/a
Z1G-PDIS.Op.neut = 1
Z1G-PDIS.Op.general = 1
A-B Z1 fault
Z1P-PDIS.Op.phsA = 1
Z1P-PDIS.Op.phsB = 1
Z1P-PDIS.Op.phsC = 0
Z1P-PDIS.Op.neut = n/a
Z1P-PDIS.Op.general = 1
Z1G-PDIS.Op.phsA = n/a
Z1G-PDIS.Op.phsB =n/a
Z1G-PDIS.Op.phsC = n/a
Z1G-PDIS.Op.neut = 0
Z1G-PDIS.Op.general = 0
So there are 6 values – although note Z1G-PDIS.Op.general is the same meaning as Z1G-PDIS.Op.neut
But if I use the intended semantic Z1-PDIS.Op.phsA and Z1-PDIS.Op.neut, then Z1-PDIS.Op.general makes sense as
APh-G Z1 fault
Z1-PDIS.Op.phsA = 1
Z1-PDIS.Op.phsC = 0
Z1-PDIS.Op.phsB = 0
Z1-PDIS.Op.neut = 1
Z1-PDIS.op.general = 1
A-Bph Z1 fault
Z1-PDIS.Op.phsA = 1
Z1-PDIS.Op.phsB = 1
Z1-PDIS.Op.phsC = 0
Z1-PDIS.Op.neut = 0
Z1-PDIS.Op.general = 1
So I only need to publish 4 values
The interpretation problem is that the second dot point in 5.11.1 might suggest the first approach should be used since the Z1 ph-G settings are operating “in parallel” to the ph-ph settings. They are in parallel in the sense that they both individually will require a PTRC.Op to be = 1
But in reality they are not operating in parallel as a ph-G element will not operate for a ph-ph fault or vice versa
Hence the second approach is actually more accurate
Same for PTOC for phase faults vs earth faults.
Yes both elements may well be in the process of “operating” for a given current, but the EF element (if IDMT) will be operating at a faster rate than the OC element since the fault is much larger x the EF setting current.
So again not really operating in parallel with the same speed performance
Hence the second approach is more accurate
1 OCStage1-PTOC1.StrVal with corresponding
1.1 OCStage1-PTOC1.Str.phsA
1.2 OCStage1-PTOC1.Str.phsB
1.3 OCStage1-PTOC1.Str.phsC
1.4 OCStage1-PTOC1.Str.neut
1.5 OCStage1-PTOC1.Str.general
1.6 OCStage1-PTOC1.Op.phsA
1.7 OCStage1-PTOC1.Op.phsB
1.8 OCStage1-PTOC1.Op.phsC
1.9 OCStage1-PTOC1.Op.neut
1.10 OCStage1-PTOC1.Op.general
2 OCStage2-PTOC2.StrVal with corresponding
2.1 OCStage2-PTOC2.Str.phsA
2.2 OCStage2-PTOC2.Str.phsB
2.3 OCStage2-PTOC2.Str.phsC
2.4 OCStage2-PTOC2.Str.neut
2.5 OCStage2-PTOC2.Str.general
2.6 OCStage2-PTOC2.Op.phsA
2.7 OCStage2-PTOC2.Op.phsB
2.8 OCStage2-PTOC2.Op.phsC
2.9 OCStage2-PTOC2.Op.neut
2.10 OCStage2-PTOC2.Op.general
3 OCStage3-PTOC3.StrVal with corresponding
3.1 OCStage3-PTOC3.Str.phsA
3.2 OCStage3-PTOC3.Str.phsB
3.3 OCStage3-PTOC3.Str.phsC
3.4 OCStage3-PTOC3.Str.neut
3.5 OCStage3-PTOC3.Str.general
3.6 OCStage3-PTOC3.Op.phsA
3.7 OCStage3-PTOC3.Op.phsB
3.8 OCStage3-PTOC3.Op.phsC
3.9 OCStage3-PTOC3.Op.neut
3.10 OCStage3-PTOC3.Op.general
4 OCStage4-PTOC4.StrVal with corresponding
4.1 OCStage4-PTOC4.Str.phsA
4.2 OCStage4-PTOC4.Str.phsB
4.3 OCStage4-PTOC4.Str.phsC
4.4 OCStage4-PTOC4.Str.neut
4.5 OCStage4-PTOC4.Str.general
4.6 OCStage4-PTOC4.Op.phsA
4.7 OCStage4-PTOC4.Op.phsB
4.8 OCStage4-PTOC4.Op.phsC
4.9 OCStage4-PTOC4.Op.neut
4.10 OCStage4-PTOC4.Op.general
5 EFStage1-PTOC5.StrVal with corresponding
5.1 EFStage1-PTOC5.Str.phsA
5.2 EFStage1-PTOC5.Str.phsB
5.3 EFStage1-PTOC5.Str.phsC
5.4 EFStage1-PTOC5.Str.neut
5.5 EFStage1-PTOC5.Str.general
5.6 EFStage1-PTOC5.Op.phsA
5.7 EFStage1-PTOC5.Op.phsB
5.8 EFStage1-PTOC5.Op.phsC
5.9 EFStage1-PTOC5.Op.neut
5.10 EFStage1-PTOC5.Op.general
6 EFStage2-PTOC6.StrVal with corresponding
6.1 EFStage2-PTOC6.Str.phsA
6.2 EFStage2-PTOC6.Str.phsB
6.3 EFStage2-PTOC6.Str.phsC
6.4 EFStage2-PTOC6.Str.neut
6.5 EFStage2-PTOC6.Str.general
6.6 EFStage2-PTOC6.Op.phsA
6.7 EFStage2-PTOC6.Op.phsB
6.8 EFStage2-PTOC6.Op.phsC
6.9 EFStage2-PTOC6.Op.neut
6.10 EFStage2-PTOC6.Op.general
7 EFStage3-PTOC7.StrVal with corresponding
7.1 EFStage3-PTOC7.Str.phsA
7.2 EFStage3-PTOC7.Str.phsB
7.3 EFStage3-PTOC7.Str.phsC
7.4 EFStage3-PTOC7.Str.neut
7.5 EFStage3-PTOC7.Str.general
7.6 EFStage3-PTOC7.Op.phsA
7.7 EFStage3-PTOC7.Op.phsB
7.8 EFStage3-PTOC7.Op.phsC
7.9 EFStage3-PTOC7.Op.neut
7.10 EFStage3-PTOC7.Op.general