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3RT1/3RH1 contactors
SIRIUS System Manual
3-6
GWA 4NEB 430 0999-02b
Rated operational cur-
rents
The rated operational currents for the various utilization categories are listed
in the low-voltage switching devices catalog. The test specifications given in
the table for each utilization category represent the scale for the making and
breaking capacity of the auxiliary contacts.
Example
3RT1016 contactor:
I
e
/AC-15 of the auxiliary contact: 6 A/230 V
Making capacity: 10 x I
e
/AC-15 = 60 A
• This enables the contactor coil with the greatest power consumption
(3TF56) to be switched on.
• Current value of the contactor coil when switched on: 10.7 A
• Only the holding current is decisive for switching off the contactor coil:
Approximately 0.5 A in the example
According to regulations, the auxiliary contact must normally be able to
switch off the rated operational current.
Utilization category for
DC voltage
(auxiliary contact ele-
ments)
Table 3-4: Utilization categories, test conditions for DC voltage (auxiliary contact elements)
Definition of DC-12 to
DC-14
The DC voltage switching capacity of auxiliary contacts is defined in utiliza-
tion categories DC-12 to DC-14.
The main areas of application for contactors are:
• DC-12: switching of resistive loads (typical application)
• DC-13: switching of inductive loads, such as contactor coils and solenoid
valves
In DC operation, the difference in stress is also determined by the L/R time
constant. This must be specified by the user.
DC
Utilization category for DC
voltage (auxiliary contact ele-
ments)
Switching capacity
Make
I/I
e
Break
I/I
e
L
/
R
(ms)
DC-12
Control of resistive load and
semiconductor load in the
input circuits of optocouplers
1
1
1
DC-13
Control of solenoids
1
1
300
DC-14
Control of electromagnetic
loads with economy resistors
in the circuit
10
1
15