Siemens SENTRON 3WL10 - Page 76

Description
2.8 Electronic trip unit ETU
3VA27 molded case circuit breakers & 3WL10 air circuit breakers
74 Manual, 10/2018, L1V30499596002-01
Electronic trip units of the 6-series
Protection functions of the ETU
ETU650 LSI
ETU660 LSIG
L
LT: Overload protection
Protection function can be enabled/disabled Via rating plug "L = off" Via rating plug "L = off"
Setting range of operating value I
r
= I
n
x … 0.4 to 1 (in steps of 0.001)
Default value: 1
Tolerance
1)
: Tripping
between 1.05 and 1.2 x I
r
0.4 to 1 (in steps of 0.001)
Default value: 1
Tolerance
1)
: Tripping
between 1.05 and 1.2 x I
r
Setting range for delay time t
r
at I²t
(reference point 6 x I
n
)
0.75 to 36 s (in steps of 0.25)
Default value: 36 s
Tolerance
1)
:
± 10% I ≤ 6 x I
n
± 20% I > 6 x I
n
0.75 to 36 s (in steps of 0.25)
Default value: 36 s
Tolerance
1)
:
± 10% I ≤ 6 x I
n
± 20% I > 6 x I
n
Switchable overload protection characteristic
IEC 60255-151
t
trip
=(t
r
∙b)/((I
load
/I
r
)^
α
-1)
I
4
t: α=4, b=1296
standard inverse SI: α=0.02,
b=0.0364
very inverse VI: α=1, b=5
extremely inverse EI: α=2,
b=35.2
Default value: I²t
I
4
t: α=4, b=1296
standard inverse SI: α=0.02,
b=0.0364
very inverse VI: α=1, b=5
extremely inverse EI: α=2,
b=35.2
Default value: I²t
Setting range for delay time t
r
for characteristic
IEC 60255-151
(reference point 6 x I
n
)
0.75 to 5 s (in steps of 0.25)
Default value: 5 s
Tolerance
1)
:
± 10% I ≤ 6 x I
n
± 20% I > 6 x I
n
0.75 to 5 s (in steps of 0.25)
Default value: 5 s
Tolerance
1)
:
± 10% I ≤ 6 x I
n
± 20% I > 6 x I
n
Thermal memory can be enabled/disabled
●
●
Overload pre-alarm 50 to 100% x I
r
(in steps of
1%)
Default value: 90%;
50 to 100% x I
r
(in steps of
1%)
Default value: 90%;
S
ST: Short-time-delayed short-circuit protection
Protection function can be enabled/disabled
●
●
Setting range of operating value I
sd
= I
n
x … 0.6 to 10 (in steps of 0.1)
Default value: OFF
Tolerance
1)
:
± 7% I ≤ 6 x I
n
± 10% I ≤ 6 x I
n
0.6 to 10 (in steps of 0.1)
Default value: OFF
Tolerance
1)
:
± 7% I ≤ 6 x I
n
± 10% I ≤ 6 x I
n
Short-circuit protection characteristic Switchable
I²t / t = constant
Switchable
I²t / t = constant
Setting range for delay time t
sd
(fixed delay) t=k 0.05 to 0.4 s (in steps of
0.01)
Default value: 0.05
Tolerance
1)
: The better value
out of ± 10% or ± 40ms
0.05 to 0.4 s (in steps of
0.01)
Default value: 0.05
Tolerance
1)
: The better value
out of ± 10% or ± 40ms
Setting range for delay time t
sd
at I²t (reference
point 10 x I
n
)
0.05 to 0.5 s (inverse-time in
relation to I²t) (in steps of
0.01)
0.05 to 0.5 s (inverse-time in
relation to I²t) (in steps of
0.01)
Tripping can be deactivated
●
●