Siemens siprotec 7SA522 User Manual

Functions
6-98 7SA522 Manual
C53000-G1176-C119-2
Definite Time Very
High Set Current
Stage 3I
0
>>>
The earth current I
E
is passed through a numerical filter and then compared with the
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
0
>>>–stage. The function modules “direction deter-
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).
Figure 6-57 Logic diagram of the 3I
0
>>>–stage
Definite Time High
Set Current
Stage 3I
0
>>
The logic of the high set current stage 3I
0
>> is the same as that of the 3I
0
>>>–stage.
In all references 3I0>>> must merely be replaced by ,!!. Otherwise, Figure 6-57
also applies.
Definite Time
Overcurrent
Stage 3I
0
>
The logic of the overcurrent stage 3I
0
> is the same as that of the 3I
0
>>>–stage. In all
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.
I
E
3I
0
>>>
Yes
No
Reverse
Forward
Non-Direct.
„1“
≥1
&
&
inrush-
stabilization
direction-
determination
forwards
reverse
&
&
Yes
No
,!!!627)7ULS

Yes
No
permissive
teleprot..
switch onto
fault
≥1
EF 3I0>>> TRIP
T0
 7627)7LPH '(/$<

T0
&
&
PICKUP
PICKUP+DIRECT.

&
627)2S0RGH
1305 >EF BLK 3I0>>>

1354
EF 3I0>>>Pickup
1366
,!!!,QUXVK%ON


,!!!7HOHS%,
≥1
>EF Inst TRIP
,!!!

7,!!!
2SPRGH,!!!
Inactive

Siemens siprotec 7SA522 Specifications

General

Brand	Siemens
Model	siprotec 7SA522
Category	Protection Device
Language	English