ABB RELION 630 Series Technical Manual page 290

Section 7
Power management functions
284
Subnetwork
SLS_TRG_BB1
BB1_SN_NO
calculation
Subnetwork
SLS_TRG_BB4
BB4_SN_NO
calculation
LS_BLOCK1
LS_BLOCK2
LS_BLOCK3
LS_BLOCK4
GUID-29E97339-7FA9-4291-A222-C5794C453467 V1 EN
Figure 154: Calculation of slow load-shed trigger signal for subnetworks
The module receives the slow load-shed enable signals,
SLS_ENA_BB1...SLS_ENA_BB4, for busbar 1...4 from NPMMXU function. If
any of the busbar slow load-shed enable signal is active, slow load-shed is enabled in
corresponding subnetwork. If slow load enable signal is inactive for all busbars in a
subnetwork, slow load-shed trigger is inhibited for corresponding subnetwork.
Figure 155 shows slow load-shed enable signals for different subnetworks for various
conditions.
OR
Slow LS
OR
trigger
OR
Slow LS
trigger
OR
1MRS757256 F
SLS_TRG_SNW1
AND
SLS_TRG_SNW2
AND
SLS_TRG_SNW3
AND
SLS_TRG_SNW4
AND
PML630/Compact Load-Shedding Solution
Technical Manual