' $ ! $!& #$"&&"! Ċ (%& !' $$ !"
5 - 17
Siemens AG ⋅ January 1999
5.3.4 Settings for fault detection - block 74
The differential protection is equipped with fault data
storage (see section 4.5.2, page 4 - 16). A distinction
is made between the reference time and the storage
criterion. As a rule, the reference time is the device
trip (ST.TRIP) which also serves as the storage criteĆ
rion. Alternatively, fault detection can also be selected
as reference time (see section 4.3.8), whereby the
storage criterion can also be the fault detection (
) or the device trip command ( ).
A fault begins with the tripping by the differential proĆ
tection function or the remote tripping and ends with
the drop off of the last fault detection. For the
7SD600 this is also the extent of a fault record.
The actual storage time begins with pre-fault time T
PRE before the reference time and ends with the
post-fault time T POS after the storage criterion has
disappeared. The maximum permissible overall stoĆ
rage time per fault record is set as T MAX. Overall, a
total of maximum5sisavailable for
fault storage. This period allows for storage of up to 8
fault records.
Y
B
7 4 FAULT
S T O R
"
[7400]
Beginning of "Fault storage" block
A
7 4 S T O F
S T . TRIP
B
+ S P . TRIP
S P . STA
[7402]
Fault data storage is activated:
D Trip command as reference time and trip comĆ
mand as storage criterion
D General fault detection as reference time and trip
command as storage criterion
D General fault detection as reference time and geĆ
neral fault detection as storage criterion
A
7 4 T M A X
2 . 0 0 s
B
[7410]
Maximum time available for fault value storage
Lowest setting: 0.30 s...............
Highest setting: 5.00 s...............
A
7 4 T PRE
0 . 2 0 s
B
[7411]
Period before starting time (reference time according
to the selected event for fault storage activation), at
which the fault value storage should begin
Lowest setting: 0.05 s...............
Highest setting: 0.50 s...............
A
7 4 POS
0 . 1 0 s
Y
[7412]
Period after drop off of the storage criterion after
which recording of the fault values should end
Lowest setting: 0.05 s...............
Highest setting: 0.50 s...............
To Next Page
Loading...
Need help?
General
