Function Block; Logic Diagram - ABB REL 501-C1 2.5 Technical Reference Manual

7.3
7.4
Current reversal and weak-end infeed logic
(ZCAL)

Function block

ZCAL-
ZCAL
BLOCK TRWEI
IRV TRWEIL1
IRVL1 TRWEIL2
IRVL2 TRWEIL3
IRVL3 IRVL
IRVBLK IRVLL1
IRVBLKL1 IRVLL2
IRVBLKL2 IRVLL3
IRVBLKL3 ECHO
CBOPEN ECHOL1
VTSZ ECHOL2
WEIBLK ECHOL3
WEIBLK1
WEIBLK2
WEIBLK3
CRL
CRLL1
CRLL2
CRLL3
xx00000186.vsd
Figure 43: Function block for the ZCAL function, when used together with phase segregated
scheme communication logic
ZCAL-
ZCAL
BLOCK TRWEI
IRV
IRVL
IRVBLK
ECHO
CBOPEN
VTSZ
WEIBLK
CRL
xx01000186.vsd
Figure 44: Function block for the ZCAL function, when used together with the three phase
scheme communication logic

Logic diagram

tPickUp
ZCAL-IRVLn
ZCAL-IRVBLKLn
Figure 45: Current reversal logic.
tPickUp
10 ms
t t
t
Line distance
tDelay
ZCAL-IRVLLn
t
&
99000193.vsd
Chapter 4
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