Siemens SENTRON 3WL10 Series Manual page 61

Protection functions of the ETU
G direct GF direct: Ground-fault protection direct
measurement
Protection function can be selected
R - residual-current protection
•
c
(with summation current transformer)
G - ground-fault return protection
•
ret
(transformer in the star point)
Rc - residual-current protection
(with summation current transformer)
Setting range operating value residual
current I
∆n
Setting range for delay time t
Gret ground-fault return protection
(ground return - transformer in the star point)
Design of G
ret
(ground fault return CT, I
Setting range operating value ground fault
return I = I
g_ret
Setting range of delay time t
Setting range for delay time t
(reference point 4 x I
Ground-fault return protection pre-alarm
Switchover to alternative operating values with
ground-fault current during the switch-on phase
(inrush adaptation) for tripping characteristic t=k
(fixed) possible
Setting range of the switch-on phase
(inrush adaptation)
Setting range I
phase (inrush adaptation)
Air circuit breaker 3WL10
Manual, 11/2017, L1V30499596002-01
∆n
transformer
)
CT_rating
x ...
CT_rating
(fixed) t=k
g_ret
at I²t
g_ret
)
n
= I x ... during the switch-on
g n
ETU650 LSI
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Description
2.4 Electronic trip unit ETU
ETU660 LSIG
●
Default set: Not installed
Ground return CT; Rc CT;
necessary
●
Alternative to GF and G_ret
Default value: OFF
Possible with current sensor
Rc & MF advanced
3; 5; 7; 10; 20; 30 A
Default value: OFF
Possible with current sensor
Rc & MF advanced
0.06; 0.1; 0.2; 0.3; 0.4; 0.5;
0.8 s
●
Alternative to GF and Rc
100; 250 A
Default value: 100 A
0.1 to 1 x I (in steps of
CT_rating
0.001)
Default value: 0.1
0.1 to 1 s (in steps of 0.05)
Default value: 0.1s
0.1s to 1s (in steps of 0.05)
50 to 90 % x I (in steps of
r
1%)
Default value: 90 %
●
Default value: OFF
0.1 to 30 s (in steps of 0.01)
Default value: 0.1
0.1 to 1 (in steps of 0.01)
Default value: 1
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