Parameter assignment/addressing
10.1 Setting the parameters
3VL molded-case circuit breakers
136
System Manual, 03/2009, 110 0110 - 02 DS 01
Parameter
Setting buttons
Effect on
characteristic curve
Brief description
Reason
I
R
.5
.8
.7 .63
.9
.6
.45
.4
.95
1.0
x
I
n
R
I
Tripping current of the
overload protection I
R
=
0.4 to 1 x I
n
Limitation of the overload range
by setting to the operating current
of the circuit to be protected
L
t
R
2.5
17
14
20
(S)
R
t
30
25
10
8
6
4
Delay (or time-lag
class) in the overload
range. The set time is
the tripping time at 6 x
I
R
. t
R
= 2.5 to 30s
Improved selectivity in the
overload range in switching
stations with several grade levels
when the rated currents differ
only slightly
I
sd
1.5
2.5
6
5
7
sd
10
8
4
3
2
x
I
R
I
Tripping current of the
short-time delay short-
circuit protection I
sd
=
1.5 to 10 x I
R
Limitation of the short-circuit
range in which the current has to
be shut off faster than in the
overload range, but with a shorter
time delay to achieve time
selectivity to downstream
switchgear
I
2
t
sd
.4
.5
.2
.3
.4
.3
.2
.1
.1
t
sd
(S)
t
I
I
ON
2
t
2
OFF
0
Switchover from a
constant time delay to a
I
2
t characteristic curve
in the short-circuit
range I
2
t
sd
= ON or OFF
Improved selectivity with
downstream switchgear, e.g.
LVHRC fuses
S
t
sd
.4
.5
.2
.3
.4
.3
.2
.1
.1
t
sd
(S)
t
I
I
ON
2
t
2
OFF
0
Delay time of the short-
circuit protection.
Please note: The
selection between t
sd
=
constant and I
2
t
characteristic t
sd
= 0 to
0.5 s with the position
of the rotary encoding
switch
Improved selectivity of the short-
circuit protection in switching
stations with several grade levels
I
I
i
1.25
1.5
6
8
x
I
n
5
4
3
2
10
i
I
11
Tripping current of the
instantaneous short-
circuit release I
i
= 1.25
to 11 x I
n
Limitation of the short-circuit
range in which the impermissibly
high current has to be switched
off as quickly as possible. This
also takes place for the self
protection of the circuit breaker
Содержание SENTRON 3VL series
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Страница 10: ...Table of contents 3VL molded case circuit breakers 10 System Manual 03 2009 110 0110 02 DS 01 ...
Страница 40: ...System overview 4 2 Key data 3VL molded case circuit breakers 40 System Manual 03 2009 110 0110 02 DS 01 ...
Страница 350: ...Correction sheet 3VL molded case circuit breakers 350 System Manual 03 2009 110 0110 02 DS 01 ...
Страница 358: ...Glossary 3VL molded case circuit breakers 358 System Manual 03 2009 110 0110 02 DS 01 ...
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