FUNCTION CHARACTERISTICS
64
NA30 - Manual - 04 - 2022
Fun_50-51S1.ai
I
L1
I
L2
t
>RES
T
0
RESET
t
>
0
T
≥
1
≥
1
≥
1
t
>def
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, Block4
&
T
0
t
CLP>
&
2nd harmonic restraint enable (ON
≡
Enable)
I>2ndh-REST
ICLP>Mode
I
CLP>def
t
CLP>
I
CLP>inv
I
L1
≥
I
>
BF Enable (ON
≡
Enable)
I>BF
towards BF logic
I> BF
&
Trip I>
TR
IP
PIN
G
M
AT
RIX
(
LE
D+R
EL
AY
S)
I
> Curve
0
T
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>
&
State
I
>
inv
I
L1
≥
I
>
def
I
L1
≥
I
>
inv
I
>
def
&
State
Phase overcurrent (50/51) - First element logic diagram (I>)
