53
NA11 - Manual - 02 - 2009
FUNCTION CHARACTERISTICS
Fun_50-51S1.ai
I
L1
I
L2
t
>RES
T0
RESET
t
>
0T
≥1
≥1
t
>def
I
>def
I
>inv
t
>inv
t
>RES
Start I>
Trip I>
CB-State
Start I
2ndh>
ON≡Inhibit (from I>> and/or I>>> overcurrent element)
ON≡Enable I> overcurrent element
(Pickup within CLP)
(Pickup outside CLP)
I> inhibition
Block1, Block2
&
T0
t
CLP>
&
2nd harmonic restraint enable (ON≡Enable)
I>2ndh-REST
ICLP>Mode
I
CLP
>def
t
CLP
>
I
CLP
>inv
I
L1
≥ I >
I
L1
≥ I >
BF Enable (ON≡Enable)
I>BF
towards BF logic
I> BF
&
Trip I >
TRIPPING MATRIX
(LED+RELAYS)
I> Curve
0T
A
B
C
A =“1”A =“0 or OFF”
Output t
CLP>
I
L3
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
I>TR-K
I>TR-L
I>ST-L
I>ST-K
≥1
CLP I>
Phase overcurrent (50/51) - First element logic diagram (I>)