Siemens SENTRON 3VL series - Page 112

Displays and operator controls
8.1 Overcurrent trip unit without LCD display
3VL IEC molded case circuit breakers
112 System Manual, 11/2013, 110 0110 - 02 DS 03
Characteristic
curve
Application
View
ETU10 for system protection, LI/LIN function
Overload protection I
R
= 0.4; 0.45; 0.5 to
0.95; 1 x I
n
, time-lag class t
R
= 2.5 to 30
Short-circuit protection (instantaneous)
I
i
= 1.25 to 11 x I
n
(size dependent)
"SB", "MB", "LB", "TB" and "NB" versions
Neutral conductor protection
I
n
= 50% / 100% x I
R
, "TA", "LA" and "NA"
versions
ETU20 for system and generator protection,
LSI / LSIN function
Overload protection I
R
= 0.4; 0.45; 0.5 to
0.95; 1 x I
n
Short-circuit protection (short-time delay)
I
sd
= 1.5 to 10 x I
R
, t
sd
= 0 to 0.5 s
I
2
t selectable on / off
Short-circuit protection (instantaneous)
I
i
= 11 x I
n
(fixed setting, size dependent)
"SE", "ME", "LE", "TE" and "NE" versions
Neutral conductor protection
I
n
= 50% / 100% x I
R
, "TF", "LF" and "NF"
versions
ETU12 for system protection,
LIG / LING function
Overload protection I
R
= 0.4; 0.45; 0.5 to
0.95; 1 x I
n
time-lag class t
R
= 2.5 to 30
Short-circuit protection (instantaneous)
I
i
= 1.25 to 11 x I
n
(size dependent)
On 4-pole molded case circuit breakers:
neutral conductor
protection 50% / 100% × I
R
"TN"and "NN" versions
Ground-fault protection:
I
g
= 0.6 / 1.0 I
n
, t
g
= 0.1 / 0.3 s
measuring method No. 1: (G
R
) vectorial
summation current formation in the three
phases and neutral conductor (4-conductor
systems); I
Δn
= I
n
, versions "SL", "SF", "ML",
"MF", "TN", and "NN"