Thytronic DMC3S, Manual

Page: 53 / 110

53
DMC3S - Manual - 08 - 2021
Second harmonic restraint
Asecond harmonic restraint block can be set by setting to
ON
the parameter
IEeme>2ndh-
REST
.
The related parameters are available in the menu Set \ Protections \ Residual emergency overcur-
rent - 51N(Eeme) \ Threshold IEeme> \ Parameters.
I
SQL
t
SQL>RES
T 0
RESET
t
SQL>
0 T
≥ 1
≥ 1
t
SQL>inv
t
SQL>RES
Start I
SQL
>
Trip I
SQL
>
Start I
2ndh>
ON ≡ Enable I> overcurrent element
Block1, Block2
&
&
2nd harmonic restraint enable (ON ≡ Enable)
I>2ndh-REST
TR
IP
PI
NG M
AT
RI
X
(LE
D+R
EL
AY
S)
I
SQL
> Curve
0 T
ISQL> Enable
I>TR-K
I>TR-L
I>ST-L
I>ST-K
&
State
I
SQL
>
inv
I
SQL
≥ I
SQL
>
def
I
SQL
≥ I
SQL
>
inv
I
SQL
>
def
&
State
&
EnTcI
SQL
>def
“0”
t
SQL>def
t
CISQL>def
t
atcI
>
def
t
atcI SQL
>
def
CB control
0 =
t
SQL>def
1 =
t
CISQL>def
“1”
CB control
tatcISQL>def
tcISQL>def tSQL>def tSQL>def
BREAKER OPEN
Breaker state
Shrink time enable
Threshold timer
t
BREAKER CLOSED
OFF
Shrink time trip
ON
Functional diagram of the threshold of the neutral current unbalance function 51(SQL)