Siemens siprotec 7SA522 User Manual page 246

Functions
Definite Time Very
High Set Current
Stage 3I >>>
0
"D333
"
I
E
3I >>>
0
1305 >EF BLK 3I0>>>
"D333D…ˆ†u7yx
" $
Yes
inrush-
No
stabilization
PƒÀ‚qrÃ"D333
" 
Inactive
Forward
Reverse
„1"
Non-Direct.
forwards
direction-
reverse
determination
Figure 6-57 Logic diagram of the 3I
Definite Time High
Set Current
Stage 3I >>
0
Definite Time
Overcurrent
Stage 3I >
0
6-98
The earth current I is passed through a numerical filter and then compared with the
E
set value ,!!!. If this value is exceeded and alarm is issued. After the correspond-
ing delay times 7 ,!!! have expired, a trip command is issued which is also
alarmed. The reset threshold is approximately 5 % + 0,5 mA below the pick-up thresh-
old.
The possibilities of intervention are referred to in the heading "General". Figure 6-57
shows the logic diagram of the 3I
mination", "permissive teleprotection", "switch onto fault", and "inrush stabilization" are
common to all stages and described below. They may however affect each stage in-
dividually. This is done with the following parameters:
• 2S PRGH ,!!!, determines the operating direction of the stage: )RUZDUG,
5HYHUVH or 1RQ'LUHFWLRQDO,
• ,!!! 7HOHS%,, determines whether a non-delayed trip with the teleprotection
scheme is possible (<HV) or not possible (1R),
• ,!!!627)7ULS, determines whether during energization of the feeder onto a
fault tripping with this stage shall be non-delayed (<HV) or not (1R) and
• ,!!!,QUXVK%ON, which is used to switch the inrush stabilization (rush blocking)
on (<HV) or off (1R).
&
&
" "
permissive
teleprot..
&
&
≥1
&
switch onto
fault
>>>–stage
0
The logic of the high set current stage 3I
In all references 3I0>>> must merely be replaced by ,!!. Otherwise, Figure 6-57
also applies.
The logic of the overcurrent stage 3I
references 3I0>>> must merely be replaced with ,!. Otherwise, Figure 6-57 also
applies. A fourth, definite time stage can be implemented by setting the "inverse" stage
(refer to the next paragraph) to a definite time stage.
>>>–stage. The function modules "direction deter-
0
UÃ"D333
" !
T
"D333ÃUryrƒ7D
Yes
≥1
No
>EF Inst TRIP
" &! TPUAÃPƒÃH‚qr
" #
PICKUP+DIRECT.
PICKUP
&
" &" UTPUAÃUv€rÃ9@G6`
>> is the same as that of the 3I
0
> is the same as that of the 3I
0
1354 EF 3I0>>>Pickup
0
≥1
1366 EF 3I0>>> TRIP
&
"D333TPUAU…vƒ
Yes
T 0
No
>>>–stage. In all
0
C53000-G1176-C119-2
>>>–stage.
0
7SA522 Manual