Siemens SENTRON 3VL series - Page 113

Displays and operator controls
8.1 Overcurrent trip unit without LCD display
3VL IEC molded case circuit breakers
System Manual, 11/2013, 110 0110 - 02 DS 03
113
Characteristic
curve
Application
View
ETU22 for system and generator protection,
LSIG / LSING function
Overload protection I
R
= 0.4; 0.45; 0.5 to
0.95; 1 x I
n
,
Short-circuit protection (short-time delayed)
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)
On 4-pole molded case circuit breakers:
neutral conductor
protection 50% / 100% × I
R
"TH" and "NH" 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-wire
systems);
I
Δn
= I
n
, versions "SG", "MG", "SH", "MH",
"TH", "NH"
ETU10M for motor and generator protection,
LI function
Finely adjustable overload protection
I
R
= 0.41; 0.42 to 0.98; 0.99; 1 x I
n
,
Trip class t
C
= 10 (fixed setting)
Thermal image
Short-circuit protection (instantaneous)
I
i
= 1.25 to 11 x I
n
(size dependent) with
phase failure sensitivity (40% I
R
fixed
setting)
"SP" and "MP" versions
ETU30M for motor and generator protection,
LI function
Finely adjustable overload protection
I
R
= 0.41; 0.42 to 0.98; 0.99; 1 x I
n
,
Trip class t
C
= 10, 20, 30
Thermal image
Short-circuit protection (instantaneous)
I
i
= 6 to 11 x I
n
with phase failure sensitivity
(40% I
R
fixed setting)
"SS", "MS" and "LS" versions