Micom P631, Technical Manual

Page: 167 / 638

The P631 checks that the reference currents and matching factors are within
their permissible ranges. The matching factors must satisfy the following
conditions:
●
The matching factors must always be ≤ 16.
●
The value for the second highest matching factor (k
am,mid
) must always be
≥ 0.5.
Should the P631 calculate reference currents or matching factors not satisfying
the above conditions then an alarm will be issued and the P631 will be blocked
automatically.
The measured values of the phase currents of the windings of the protected
object are multiplied by the relevant matching factors and are then available for
further processing. Consequently, all threshold values and measured values
always refer back to the relevant reference currents rather than to the
transformer nominal currents or the nominal currents of the device.
62Z8013A
kam,a > 16
kam,b > 16
SFMON:
2nd match.fact. inv.
[ 091 006 ]
DIFF:
Ref. curr. Iref,a
[ 019 023 ]
DIFF:
Ref. curr. Iref,b
[ 019 024 ]
SFMON:
Iref, a inval. range
[ 091 007 ]
SFMON:
Iref, b inval. range
[ 091 008 ]
DIFF:
Matching fact. kam,a
[ 004 105 ]
DIFF:
Matching fact. kam,b
[ 004 106 ]
SFMON:
Matching fail. end a
[ 091 000 ]
SFMON:
Matching fail. end b
[ 091 001 ]
DIFF:
Sound match
303 310
MAIN:
Vnom prim. end a PSx
[ 019 017 ]
MAIN:
Vnom prim. end b PSx
[ 019 018 ]
MAIN:
Inom C.T.prim.,end a
[ 019 020 ]
MAIN:
Inom C.T.prim.,end b
[ 019 021 ]
DIFF:
Reference power Sref
[ 019 016 ]
Iref,a=Sref/Vnom,a/√3
Iref,b=Sref/Vnom,b/√3
Monit. range limits
Monit. range limits
kam,pos
kam,pos < 0.5
kam,a = Inom,a/Iref,a
kam,b = Inom,b/Iref,b
COMP
Fig. 3-78: Calculating and checking the matching factors
3 Operation
P631
P631/EN M/R-11-C // P631-310-650 3-111