Siemens SIRIUS 3RT - Page 28

Standards
2.6 Applications
SIRIUS - SIRIUS 3RT Contactors/Contactor assemblies
28 Manual, 09/2017, A5E03656507120A/RS-AE/006
Utilization categories
According to IEC 60947-4-1, the application area of and the load applied to power contactors
can be identified by looking at the specified utilization category in conjunction with the
specified rated operational current or the motor power and the rated voltage. The table below
lists the most important utilization categories for contactors.
Utilization categories
AC
Main circuit contacts: Utilization category for AC voltages
AC-1 Non-inductive or slightly inductive loads, resistance furnaces
AC-2
Slip-ring motors: starting, switching off
AC-3
Squirrel-cage motors: starting, switching-off motors during running
AC-4
Squirrel-cage motors: starting, plugging, inching
AC-5a
Switching of discharge lamp controls
AC-5b
Switching of incandescent lamps
AC-6a
Switching of transformers
AC-6b
Switching of capacitive loads
DC
Main circuit contacts: Utilization category for DC voltages
DC-1
Non-inductive or slightly inductive loads, resistance furnaces
DC-3
Shunt-wound motors: Starting, plugging, reversing, inching, dynamic braking
DC-5
Series-wound motors: Starting, plugging, reversing, inching, dynamic braking
AC
Auxiliary circuit contacts: Utilization category for AC voltages
AC-12
Control of resistive loads and solid-state loads with isolation by opto couplers
AC-14
Control of small electromagnetic loads (max. 72 VA)
AC-15
Control of electromagnetic loads (over 72 VA)
DC
Auxiliary circuit contacts: Utilization category for DC voltages
DC-12
Control of resistive loads and solid-state loads with isolation by opto couplers
DC-13
Control of electromagnets