256719 - Miller 4-Pin SL Connector Plug 2.54mm Pitch with TPA

Technical Overview of the Miller 256719 Connector

The Miller 256719 is a specialized rectangular connector plug designed for precision electrical interconnects within Miller welding power sources and industrial equipment. Engineered with a standard 2.54mm (0.100 inch) pitch, this component belongs to the SL (Stackable Linear) family of modular connectors, known for their reliability in low-power and signal applications. The housing is configured as a single-row, 4-socket plug, making it an essential component for specific wire-to-board or wire-to-wire harness assemblies found in modern welding machinery.

A critical feature of this specific SKU is the inclusion of Terminal Position Assurance (TPA). In the context of industrial electronics, TPA is a secondary locking mechanism designed to ensure that the crimped terminals are fully seated within the housing. Once the terminals are inserted, the TPA device locks them in place, preventing "terminal back-out"—a common failure mode where vibration or mechanical strain causes a pin to retreat from its contact position, leading to intermittent circuits or complete signal loss. Given the high-vibration environment of a welding shop or field site, the TPA feature significantly enhances the reliability of the machine's internal wiring.

This connector housing is manufactured to Miller's strict OEM specifications, ensuring compatibility with the mating headers or receptacles used on Miller PC boards. The material composition is selected for its electrical insulation properties and resistance to thermal cycling, ensuring it maintains structural integrity even when the welding machine operates at high duty cycles. Technicians sourcing this part can be confident in its dimensional accuracy, ensuring a secure friction lock and proper electrical continuity when paired with the appropriate crimp terminals and mating interfaces.

When integrating this component, it is vital to verify the specific pinout and wire gauge requirements of the circuit being repaired. The 2.54mm pitch is a widely recognized industry standard, but the specific keying and latching geometry of this Miller OEM part guarantees the correct orientation and retention force required for safety-critical welding control systems.