Schweitzer Engineering Laboratories SEL-351S - a0 Set Automatically; Z0 F - Forward Directional Z0 Threshold; Z0 R - Reverse Directional Z0 Threshold; Z0 F and Z0 R Set Automatically

Date Code 20010112 Loss-of-Potential, Load Encroachment, and Directional Element Logic 4-33
SEL-351S Instruction Manual
a0 Set Automatically
,IHQDEOHVHWWLQJ( $872VHWWLQJDLVVHWDXWRPDWLFDOO\DW
 D 
)RUVHWWLQJD WKH]HURVHTXHQFHFXUUHQW,

PDJQLWXGHKDVWREHJUHDWHUWKDQRIWKH
SRVLWLYHVHTXHQFHFXUUHQW,

PDJQLWXGHLQRUGHUIRUWKH]HURVHTXHQFHYROWDJHSRODUL]HGDQG
FKDQQHO,1FXUUHQWSRODUL]HGGLUHFWLRQDOHOHPHQWVWREHHQDEOHG
()

,, ¼> 
Z0F – Forward Directional Z0 Threshold
Z0R – Reverse Directional Z0 Threshold
6HWWLQJ5DQJH
WRWVHFRQGDU\$QRPLQDOSKDVHFXUUHQWLQSXWV,$,%,&
WRWVHFRQGDU\$QRPLQDOSKDVHFXUUHQWLQSXWV,$,%,&
,ISUHFHGLQJVHWWLQJ25'(5GRHVQRWFRQWDLQ9QR]HURVHTXHQFHYROWDJHSRODUL]HGGLUHFWLRQDO
HOHPHQWLVHQDEOHGWKHQVHWWLQJV=)DQG=5DUHQRWPDGHRUGLVSOD\HG
=)DQG=5DUHXVHGWRFDOFXODWHWKH)RUZDUGDQG5HYHUVH7KUHVKROGVUHVSHFWLYHO\IRUWKH
]HURVHTXHQFHYROWDJHSRODUL]HGGLUHFWLRQDOHOHPHQWVVHH)LJXUH
Z0F and Z0R Set Automatically
,IHQDEOHVHWWLQJ( $872VHWWLQJV=)DQG=5]HURVHTXHQFHLPSHGDQFHYDOXHVDUH
FDOFXODWHGDXWRPDWLFDOO\XVLQJWKH]HURVHTXHQFHOLQHLPSHGDQFHPDJQLWXGHVHWWLQJ=0$*DV
IROORZV
=) =0$*  WVHFRQGDU\
=5 =0$*] WVHFRQGDU\³]´OLVWHGLQWDEOHEHORZ
,IHQDEOHVHWWLQJ( <VHWWLQJV=)DQG=5]HURVHTXHQFHLPSHGDQFHYDOXHVDUHFDOFXODWHG
E\WKHXVHUDQGHQWHUHGE\WKHXVHUEXWVHWWLQJ=5PXVWEHJUHDWHULQYDOXHWKDQVHWWLQJ=)E\
YDOXH³]´

5HOD\&RQILJXUDWLRQ
]WVHFRQGDU\
$QRPLQDOFXUUHQW 
$QRPLQDOFXUUHQW 
E32IV – SELOGIC Control Equation Enable
5HIHUWR)LJXUH
6(/
2*,&&RQWURO(TXDWLRQVHWWLQJ(,9PXVWEHDVVHUWHGWRORJLFDOWRHQDEOHWKH]HUR
VHTXHQFHYROWDJHSRODUL]HGDQGFKDQQHO,1FXUUHQWSRODUL]HGGLUHFWLRQDOHOHPHQWVIRUGLUHFWLRQDO
FRQWURORIQHXWUDOJURXQGDQGUHVLGXDOJURXQGRYHUFXUUHQWHOHPHQWV