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Date Code 20010307
Overcurrent, Voltage, Synchronism Check, Frequency, and Power Elements
3-53
SEL-351-0, -1, -2, -3, -4 Instruction Manual
Overfrequency Element
)RUH[DPSOHPDNHVHWWLQJV
1)5(4 +]
QRPLQDOV\VWHPIUHTXHQF\LV+]
(
HQDEOHIUHTXHQF\HOHPHQW
'3 +]
IUHTXHQF\HOHPHQWSLFNXS
:LWKWKHVHVHWWLQJV
'31)5(4
WKHRYHUIUHTXHQF\SDUWRIIUHTXHQF\HOHPHQWORJLFLVHQDEOHG'DQG'7RSHUDWHDV
RYHUIUHTXHQF\HOHPHQWV'LVXVHGLQWHVWLQJRQO\
Underfrequency Element
)RUH[DPSOHPDNHVHWWLQJV
1)5(4 +]
QRPLQDOV\VWHPIUHTXHQF\LV+]
(
HQDEOHIUHTXHQF\HOHPHQW
'3 +]
IUHTXHQF\HOHPHQWSLFNXS
:LWKWKHVHVHWWLQJV
'31)5(4
WKHXQGHUIUHTXHQF\SDUWRIIUHTXHQF\HOHPHQWORJLFLVHQDEOHG'DQG'7RSHUDWHDV
XQGHUIUHTXHQF\HOHPHQWV'LVXVHGLQWHVWLQJRQO\
Frequency Element Operation
5HIHUWR)LJXUH
Overfrequency Element Operation
:LWKWKHSUHYLRXVRYHUIUHTXHQF\HOHPHQWH[DPSOHVHWWLQJVLIV\VWHPIUHTXHQF\LVOHVVWKDQRU
]'3 +]IUHTXHQF\HOHPHQWRXWSXWV
' ORJLFDO
LQVWDQWDQHRXVHOHPHQW
'7 ORJLFDO
WLPHGHOD\HGHOHPHQW
,IV\VWHPIUHTXHQF\LVJUHD]'3 +]IUHTXHQF\HOHPHQWRXWSXWV
' ORJLFDO
LQVWDQWDQHRXVHOHPHQW
'7 ORJLFDO
WLPHGHOD\HGHOHPHQW
5HOD\:RUGELW'7DVVHUWVWRORJLFDORQO\DIWHUWLPHGHOD\''