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Siemens IC 10 · 2017
Power Contactors for Switching Motors
SIRIUS 3RT12 and 3TF6 vacuum contactors
3
Contact endurance of the main contacts
特征曲线显示了接触
endurance of the contactors when switching
resistive and inductive AC loads (AC-1/AC-3)
取决于断裂电流和额定值
operational voltage. It is assumed that the oper-
ating mechanisms are switched randomly, i. e.
没有与
供应系统。
The rated operational current
I
e
符合
utilization category AC-4 (breaking 6 times the
额定运营电流），适用于
contact endurance of approximately 200 000
operating cycles.
If a shorter contact endurance is sufficient, the
rated operational current
I
e
/AC-4 can be
increased.
如果接触用于混合操作
， IE。
normal switching (breaking the rated operational
current according to utilization category AC-3) in
与间歇性的结合（断裂
额定运营电流几次
according to utilization category AC-4), the con-
tact endurance can be calculated approximately
从以下等式：
Characters in the equation:
X
混合操作的接触耐力
in operating cycles
A
Contact endurance for normal operation
(
I
a
=
I
e
) in operating cycles
B
Contact endurance for inching
(
I
a
=多个
I
e
) in operating cycles
C
占总操作的百分比
switching operations
真空接触器
类型
3TF68 and 3TF69
大小
14
X
A
1
C
100
-------
A
B
--
1
–
+
-----------------------------------------------------------------------------
=
a
(A)
Operating cycles at
Contactor type
Breaking current
NSB0_00654B
3TF68
3TF69
200
400
4
000
2
000
1
000
600
6
000
10
8
6
4
2
10
8
6
4
2
10
8
6
4
2
10
8
6
4
2
10
7
6
5
4
3
6
4
2
10
8
6
4
2
10
8
6
4
2
10
8
6
4
2
10
6
5
4
3
8
6
4
2
10
8
6
4
2
10
8
6
4
2
10
8
6
4
2
10
6
5
4
3
10
8
6
4
2
10
8
6
4
2
10
8
6
4
2
10
8
6
4
2
7
6
5
4
100
690 V
500 V
400 v
230 V
©Siemens AG 2016