FUNCTION CHARACTERISTICS
66
NA30 - Manual - 04 - 2022
Fun_50-51S2.ai
t
>>RES
T
0
RESET
t
>>
0
T
≥
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, Block4
I>
>
TR-K
I>
>
TR-L
I>
>
ST-L
I>
>
ST-K
T
0
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>>
TR
IP
PIN
G
M
AT
RIX
(
LE
D+R
EL
AY
S)
I
>> Curve
0
T
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>>
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
Phase overcurrent (50/51) - Second element logic diagram (I>>)