[foglchki-040211-01.tif, 1, en_US]
Threshold
The Threshold parameter is the lower limit of the operating range of the Current-sum supervision func-
tion.
Operate delay
When the calculated fault current (I
F
) exceeds the calculated fault current limit (I
Fmax
), the Operate delay
starts. If the threshold-value violation persists for that time, the Failure indication is generated.
Blocking the Function
The following blockings reset the picked up function completely:
•
Externally or internally via the binary input signal
>Block function
•
A protection pickup
The pickup signal of a protection function blocks the indication
Failure
.
Application and Setting Notes
Parameter: Slope factor
•
Recommended setting value (_:101) Slope factor = 0.1
The Slope factor parameter is used to set the ratio between the minimum (I
min
) and the maximum (I
max
)
phase current. This function calculates the RMS values.
Parameter: Threshold
•
Recommended setting value (_:102) Threshold = 0.1 A for I
rated
= 1 A or 0.5 A for I
rated
= 5 A
The Threshold parameter is used to set the maximum phase current (I
max
).
Parameter: Operate delay
•
Recommended setting value (_:6) Operate delay = 5.00 s
Set the Operate delay parameter so that overfunctions due to disturbing influences (such as switching
operations) are avoided.
Settings
Addr.
Parameter C Setting Options Default Setting
Supv. sum I
_:1 Supv. sum I:Mode
•
off
•
on
•
test
off
_:102 Supv. sum I:Threshold 1 A @ 100 Irated 0.030 A to 10.000 A 0.100 A
5 A @ 100 Irated 0.15 A to 50.00 A 0.50 A
1 A @ 50 Irated 0.030 A to 10.000 A 0.100 A
5 A @ 50 Irated 0.15 A to 50.00 A 0.50 A
1 A @ 1.6 Irated 0.001 A to 1.600 A 0.100 A
5 A @ 1.6 Irated 0.005 A to 8.000 A 0.500 A
_:101 Supv. sum I:Slope factor 0.00 to 0.95 0.10
9.3.11.4
9.3.11.5
Supervision Functions
9.3 Supervision of the Secondary System
1278 SIPROTEC 5, Overcurrent Protection, Manual
C53000-G5040-C017-8, Edition 07.2017