Siemens 3TM3431-1QA60-0AC0-Z Vacuum Contactor Unit

Module Feature3TM3431-1QA60-0AC0-Z belongs to Siemens 3TM series medium voltage vacuum contactor. It adopts vacuum interrupter as contact breaking unit, 3-pole layout, electromagnetic closing mechanism with low holding power consumption. It is designed for frequent make/break operation, suitable for medium voltage asynchronous motor, transformer and reactive power compensation capacitor feeder. It can be fitted with auxiliary contact set, shunt trip and mechanical interlock. It has strong vibration and dust resistance, widely used in coal mine, oil & gas and power station medium voltage cabinets for spare replacement.

Working principleWhen the closing coil is energized, the operating mechanism drives the vacuum interrupter contacts to close and lock. The vacuum arc extinguishing chamber suppresses electric arc quickly when opening. The auxiliary contacts feed back contact status to control circuit. It needs external protective relay to realize overload and short-circuit protection.

Onboard componentsVacuum interrupter assembly, electromagnetic operating mechanism, closing coil, auxiliary contact block, mechanical position indicator, insulating support frame, main terminal busbar.

LED indicatorsNo built-in LED. ON/OFF status is shown by mechanical indicator flag.

Hardware self‑diagnosisNo embedded electronic self-diagnosis. Contact wear, vacuum tightness and operating characteristic are checked in periodic high voltage test and contact resistance measurement.

Programming softwareNo supporting configuration software.

Electrical & Process ParametersModel:3TM3431-1QA60-0AC0-Z Brand:Siemens Device type:Medium voltage vacuum contactor Rated voltage:12kV Function:Frequent switching control for MV motors, transformers and capacitor banks

Mechanical & StructureMounting:Switchgear compartment fixed installation Protection class:IP20 Housing:Insulated frame with vacuum interrupter module

EnvironmentalOperating temperature:-25℃ ~ +70℃ Storage temperature:-40℃ ~ +85℃ Ambient humidity:5~95% non‑condensing

Certification:CE, IEC62271

Status:Original Siemens medium voltage switchgear spare

InstallationInstall the contactor into medium voltage switchgear compartment. Check main terminal torque, test closing coil function, auxiliary contact signal and mechanical interlock before energizing.

InterfacePrimary high voltage terminals, secondary control coil and auxiliary contact terminals.

DiagnosticFail to close: No coil control power, mechanical jam or burnt closing coil. Overheating: Poor main contact connection or contact surface ablation. Cannot open: Mechanism stuck or interlock failure.

Product BriefSiemens 3TM3431-1QA60-0AC0-Z vacuum contactor, 12kV medium voltage frequent switching contactor for mining and industrial MV switchgear maintenance replacement.