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NA11 - Manual - 02 - 2009
FUNCTION CHARACTERISTICS
Fun_50-51S2.ai
t
>>RES
T0
RESET
t
>>
0T
≥1
t
>>def
t
>>inv
t
>>RES
Start I>>
Trip I>>
CB-State
Start I
2ndh>
ON≡Inhibit (from I>>> overcurrent element)
ON≡Enable I>> overcurrent element
I>> inhibition
Block1, Block2
I>>TR-K
I>>TR-L
I>>ST-L
I>>ST-K
T0
t
CLP>>
&
&
2nd harmonic restraint enable (ON≡Enable)
I>>2ndh-REST
ICLP>>Mode
t
CLP
>>
BF Enable (ON≡Enable)
I>>BF
towards BF logic
I>> BF
&
Trip I>>
TRIPPING MATRIX
(LED+RELAYS)
I>> Curve
0T
A
B
C
Output t
CLP>>
I>> Enable
I>> overcurrent element (50/51) Block diagram
t
CLP>>
CB State CB OPEN CB CLOSED CB OPEN
Output t
CLP
>
>
t
0.1 s
HIGH THRESHOLD/
BLOCK
LOW THRESHOLD/
UNBLOCK
HIGH THRESHOLD/
BLOCK
A = ON - Change setting
B = OFF
C = ON - Element blocking
&
(ON≡
Inhibit
)
Start I>>
I> inhibition
I> disbyl>>
≥1
CLP I>>
Phase overcurrent (50/51) - Second element logic diagram (I>>)
I
L1
I
L2
≥1
≥1
(Pickup within CLP)
(Pickup outside CLP)
I
CLP
>>def
I
CLP
>>inv
I
L1
≥ I >>
A =“1”A =“0 or OFF”
I
L3
&
State
I>>
inv
I
L1
≥
I>>
def
I
L1
≥
I>>
inv
I>>
def
&
State