Features:
- The thyristor stage ramps the three-phase motor voltage during starting.
- Integrated bypass contacts carry the motor current after the acceleration sequence.
- Current limiting, overload protection, device protection, and external reset are built into the S12 starter.
Siemens 3RW4076-6BB44 separates its 200–460 V AC motor path from the 230 V AC control-supply path.
The rated current of 3RW4076-6BB44 changes with ambient temperature, so motor selection and enclosure temperature must be evaluated together.
Busbar power connections and screw-type control terminals give 3RW4076-6BB44 different conductor requirements on the two circuit sides.
The Siemens 3RW4076-6BB44 SIRIUS 3RW40 S12 Soft Starter may still be available for purchase and support from Apter Power beyond End-Of-Life (EOL) by the manufacturer (OEM).
Siemens 3RW4076-6BB44 SIRIUS 3RW40 S12 Soft Starter Manuals,Datasheets,Link
Important Notice: Other accessories, manuals, cables, calibration data, software, etc. are not included with this equipment unless listed in the above stock item description. All prices are shown in USD.
Motor Acceleration and Bypass
- Voltage ramp: The thyristor stage progressively raises the motor voltage during the configured start sequence.
- Current limit: The adjustable current limit constrains the starting current when the motor and load data are correctly selected.
- Bypass transfer: Integrated contacts take over the running current after acceleration, reducing sustained thyristor losses.
- Motor selection: Motor voltage, rated current, duty, and load profile must remain within the starter selection data.
Motor and Control-Supply Paths
- Main circuit: Three busbar-connected poles carry the 200 to 460 V AC motor supply.
- Control supply: A separate 230 V AC source powers the starter electronics at 50 or 60 Hz.
- Auxiliary contacts: Two normally open and one changeover contact report the documented operating states.
- Cable reach: The motor connection is specified for a maximum cable length of 300 m.
Current and Device Protection
- Motor setting: Electronic overload protection uses a motor-current setting that starts at 207 A.
- Device protection: Intrinsic protection supervises the starter power electronics independently of the motor-overload function.
- External reset: A remote reset input allows a latched fault to be cleared from the control circuit.
- Temperature derating: The operational-current rating falls from 432 A at 40 °C to 335 A at 60 °C.
S12 Mounting and Clearances
- Fixing method: The S12 housing attaches to the mounting surface with screws.
- Vertical clearance: The installation requires 100 mm above and 75 mm below the starter.
- Side clearance: Adjacent equipment must leave at least 5 mm at the side.
- Orientation: Permitted rotation and tilt depend on whether the additional fan is installed.