Siemens 3VT Serie Instructions De Service page 8

Operating Instructions
Setting the long-time delay overload (L) and short-circuit instantaneous (I) protection
For the VT160 circuit breaker, there are 2 versions available:
- L protection fixed (I = 1.0 x I
r
- L protection adjustable (I
r
Figure (19). The ranges of the current settings are described in Table (20).
Load capacity at various ambient temperatures
The permissible load capacity of the circuit breaker is dependent on the ambient temperature in its immediate vicinity, see Table (18).
(18)
Rated current
of frame size
I +10 °C +20 °C +30 °C +40 °C +50°C +55 °C +60 °C
n
160 A 1.15
(19) VT160 TM trip unit with adjustable I
(20)
Rated current Rated
of frame size current
I I
mn n
32 A
40 A
50 A
63 A
160 A
80 A
100 A
125 A
160 A
8
) and I protection fixed.
n
= 0.7 - 1.0 x I ) and I protection fixed. An illustration of the trip unit with adjustable L can be seen in
n
Ambient temperature
1.1 1.05 1.0 I
n
r
Min
I , current settings of long-
r
time delay protection 40 °C
A/B/C phase N pole
22.4 ~ 32 A 22.4 ~ 32 A
28 ~ 40 A 28 ~ 40 A
35 ~ 50 A 35 ~ 50 A
44.1 ~ 63 A 44.1 ~ 63 A
56 ~ 80 A 56 ~ 80 A
70 ~ 100 A 70 ~ 100 A
87.5 ~ 125 A 87.5 ~ 125 A
112 ~160 A 112 ~160 A
0.94 0.91 0.88
Max
Adjustable knob for I
Instantaneous short-circuit protection I
For power distribu-
tion protection
A/B/C phase N pole A/B/C phase
500 A 500 A
500 A 500 A
500 A 500 A
630 A 630 A
800 A 800 A
1000 A 1000 A
1250 A 1250 A
1600 A 1600 A
r
i
For motor protection
N pole
500 A 500 A
500 A 500 A
500 A 500 A
630 A 630 A
800 A 800 A
1200 A 1200 A
1500 A 1500 A
1920 A 1920 A
English
A5E00817850-01