ABB REL 551-C1*2.5 - Technical Data

75
Time delayed residual overcurrent protection
(TEF)
Chapter 5
Current
3.7 Technical data
Table 86: TEF - Time delayed non-directional residual overcurrent protection
Parameter Setting range Accuracy
Start current, definite time or inverse
time delay, IN>
5-300% of Ib in steps of
1%
± 5% of set value
Characteristic angles 65 degrees lagging ± 5 degrees at 20 V and I
set
=35%
of I
r
Definite time delay 0.000 - 60.000 s in steps
of 1ms
± 0.5 % +/-10 ms
Time multiplier for inverse time delay
k
0.05-1.10 in steps of 0.01 According to IEC 60255-3
Normal inverse characteristic
I = I
meas
/I
set
IEC 60255-3 class 5 ± 60 ms
Very inverse characteristic IEC 60255-3 class 7.5 ± 60 ms
Extremely inverse characteristic IEC 60255-3 class 7.5 ± 60 ms
Logarithmic characteristic ± 5 % of t at I = (1.3-29) × I
N
Min. operate current for dependent
characteristic, IMin
100-400% of IN in steps
of 1%
± 5% of I
set
Minimum operate time for dependent
characteristic, tMin
0.000-60.000 s in steps
of 1 ms
± 0.5 % ± 10 ms
Reset time <70 ms -
t
13.5
I1–
-----------
k⋅=
t5.81.35– ln
I
I
N
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⋅=