Product DescriptionThe SIEMENS 3TX4431-2A is an auxiliary contact block designed to expand the switching capability of compatible contactors and relay assemblies. Auxiliary contact blocks add supplementary control contacts to a base contactor, allowing additional control-circuit connections without increasing the contactor footprint. This block is a compact, hard-wired component installed by licensed electricians during panel assembly, motor control center construction, or field contactor servicing. Its small form factor and standardized mounting interface make it a practical addition to existing contactor installations in industrial and commercial electrical systems.The 3TX4431-2A is suited for use in motor control, lighting control, and machinery contactor applications where additional auxiliary contacts are required for interlocking, indicator circuits, or control-loop logic. It is typically installed in commercial and light industrial environments alongside Siemens contactor assemblies. Electricians and controls technicians working on motor starters, HVAC packaged equipment control panels, or automated machinery will encounter this type of auxiliary block as a standard expansion component.Key FeaturesAuxiliary contact block expands control-circuit switching points on compatible base contactorsCompact dimensions of 1.654 x 1.732 x 2.244 inches allow installation in tight panel spacesLightweight construction at 0.108 pounds minimizes added load on contactor assemblySnap-on or screw-mount interface typical of Siemens modular contactor accessoriesSuitable for control-circuit interlocking, status indication, and logic inputsCompatibilityDesigned as an OEM-style auxiliary contact block expansion accessory for compatible Siemens contactor platforms. Verify base contactor model acceptance of this auxiliary block before installation.Installation NotesInstallation should be performed by a qualified electrician in accordance with NEC requirements and the contactor manufacturers wiring diagrams. De-energize and lock out the contactor assembly fully before attaching or removing any auxiliary contact block. Confirm the auxiliary block is fully seated and mechanically secured to the base contactor before restoring power. Do not exceed the control-circuit voltage and current ratings marked on the assembly.Technical SpecificationsDimensions (L x W x H): 1.654 x 1.732 x 2.244 inchesWeight: 0.108 poundsUPC: 75455420317Standard InformationBrand: SIEMENSManufacturer Part Number: 3TX4431-2A